[HN Gopher] Starship Flight 5: Launch and booster catch [video]
___________________________________________________________________
Starship Flight 5: Launch and booster catch [video]
Author : alecco
Score : 1312 points
Date : 2024-10-13 12:23 UTC (9 hours ago)
(HTM) web link (twitter.com)
(TXT) w3m dump (twitter.com)
| DarmokJalad1701 wrote:
| They caught it! Holy sh*t!
| dotnet00 wrote:
| All the renders in the world couldn't have prepared me for how
| crazy the actual catch looked!
| choonway wrote:
| ok now they have an actual reference and can animate it better
| haha.
| helpfulContrib wrote:
| Amazing days ahead of us - if we can avoid blowing ourselves up
| over pathetic patches of land, we could have the entire solar
| system under our feet...
| falcor84 wrote:
| Agreed, but I'm concerned that humans being humans, we'll have
| the entire solar system to blow ourselves over.
|
| In The Expanse (which I highly recommend), they give a new
| lease on life to that quote attributed to Einstein "I know not
| with what weapons World War III will be fought with, but World
| War IV will be fought with sticks and stones" - hurling
| asteroids towards a planet. I really hope humanity's real
| future will play out in accordance with some of the more
| optimistic elements in The Expanse.
| nycdotnet wrote:
| They did it!
| jmyeet wrote:
| Stage 1 sucessfully caught. That was pretty incredible. I
| remember watching the Falcony Heavy launch when both boosters
| landed in sync.
|
| It's hanging pretty high in the air, I assume so the engines do
| less damage to the pad. One wonders how they're going to get it
| down. Do the chopsticks lower on the tower?
| chinathrow wrote:
| Yes, the chopsticks are attached to one giant lift.
| stagezerowil wrote:
| Yes, the chopsticks lower and raise. They will lower the tower
| onto a transport vehicle and send it back to the bay for
| examination, and then possible reflight.
| dotnet00 wrote:
| Yep, they handle all the mounting/demounting ops on the launch
| mount, so they have to be able to move along the tower.
| sbuttgereit wrote:
| They'll lower it to the launch mount... the catch arms are
| effectively a crane. But I wonder if it's more "toasty" than
| they were expecting? There were some fires going at catch
| (those look out, at least on external camera views) and the
| engines are still a bit.... smokey. Don't know if that's
| normal... or if they were expecting it.
|
| My hunch is that they don't put it down for awhile. If there's
| still an issue were there are fires lingering inside, my hunch
| is they want that as far from the ground infrastructure as
| possible.
|
| Either way incredible progress.
| minetest2048 wrote:
| From the replay, it seems that the fire comes from methane
| from the RCS thrusters burning, so it seems normal
| sbuttgereit wrote:
| The fire I mostly saw was coming from the quick disconnect
| ports and related plumbing. Also, there was fire on the
| other side, close to where there was part of a chine was
| clearly missing. There were a couple other things, too.
|
| Wasn't perfect, some things to work out... but still pretty
| damn good.
| chasd00 wrote:
| Remember on the first launch when, on the way up, there
| were hydraulic units exploding off the side and the
| engines started exploding taking out more hydraulic
| units? Heh that and all the concrete flying up on
| ignition was like watching a heavy metal music video.
| chasd00 wrote:
| There was a lot of smoke coming out of the bottom after the
| catch. I was worried about an internal fire but it's since
| stopped. The glow from the engine mount on re-entry was
| amazing. The fire on landing had me worried too I was
| expecting it to grow but put itself out eventually.
|
| What an amazing morning!
| BOOSTERHIDROGEN wrote:
| Congratulations.
| valenceelectron wrote:
| Although this is by far not the first landing of SpaceX boosters
| I've seen, this looked like scifi to me even in 2024.
| stagezerowil wrote:
| Holy hell, they caught the booster!
| ipnon wrote:
| Moon by 2030 and Mars by 2040 seems like a winning bet lately
| napsterbr wrote:
| And here I thought nothing would top the double landing view from
| Falcon Heavy...
| NoxiousPluK wrote:
| That was such a magical moment
| treespace8 wrote:
| I'm just so happy to see this level of progress. This another big
| step for opening up space. To think that one day this will be
| considered normal. 150 Metric tons sent on a fully reusable
| rocket.
|
| Thats like a 747 to space.
| Waterluvian wrote:
| Is that 150t of payload or total? What's the cost in fuel alone
| (let's ignore maintenance and operations costs for now)? I'm
| trying to get a feel for the relative scale compared to today's
| commercial flight.
| treespace8 wrote:
| It was just a quick google. 150t reusable.
|
| No idea about the other costs.
| dotnet00 wrote:
| They previously threw around a number of around $1M per
| flight, as mostly fuel costs.
|
| Also, while 150t is the target payload capacity, the current
| test vehicles are closer to 50t in payload capacity, there
| are revisions in the pipeline based on data from these test
| flights which will bring it up to 150t.
| pfdietz wrote:
| To put this in perspective: at 150t/launch, if a launch is
| $1M, then for the cost of an SLS launch (at least $2B)
| Starship could launch 300,000 tons, about the mass of three
| Nimitz-class nuclear aircraft carriers.
| Waterluvian wrote:
| We could use a few of those in orbit.
| mensetmanusman wrote:
| America funding the literal eye of Sauron 2.0
| pclmulqdq wrote:
| None of the vehicles have demonstrated any payload capacity
| yet. 50 tons is the on-paper capacity only, and seems quite
| high given how little fuel is left when the bring an empty
| starship to orbital altitude. I assume that as the engines
| and launch procedures get more efficient, they will start
| being able to bring stuff to orbit (and quite a bit of
| stuff, too).
| jillesvangurp wrote:
| Methane is about 900-1500$ / ton. About 1000 tons is used for
| the launch in addition to 3600 tons of lox. That should be a
| bit cheaper than methane per ton. Ballpark, the propellant
| might cost around 2M$.
|
| A modern airliner on a long flight might burn around 80 tons
| of kerosene. It's slightly cheaper than methane. Call it
| 75-80K$.
| bombcar wrote:
| That's $7 of fuel per pound of payload, that is _not bad_
| at all.
| pfdietz wrote:
| Indeed. You sometime see an argument that launch to space
| is expensive because of the propellant and therefore
| energy required. And as you note this argument is utterly
| wrong.
| throwaway4aday wrote:
| not sure how anyone can miss the "throwing away the
| airplane" part as being the cost driver.
| pfdietz wrote:
| It's the same cognitive error as thinking nuclear energy
| must be cheap because the fuel is cheap.
| zaroth wrote:
| Is the $1000/ton a law a physics, or could that ever
| possibly scale up and come down an order of magnitude?
| pfdietz wrote:
| There are no dollars in the laws of physics. It's
| connected ultimately to productivity of all the
| activities involved, and there's no obvious upper bound
| to productivity.
| WalterBright wrote:
| There's the rocket equation.
|
| https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
| pfdietz wrote:
| Which doesn't have dollars anywhere in it.
| WalterBright wrote:
| The point of the rocket equation is there are hard
| physical limits on what rockets can do, and dollars won't
| change it.
| pfdietz wrote:
| That's nice. It doesn't imply a lower bound for costs,
| just of ratios of costs.
| flaburgan wrote:
| So, reusable is supposed to reduce the cost. But the space
| shuttle was reusable and it has been shutdown because it was
| too expensive. What is the differences between the two?
| kortilla wrote:
| SRB and tank were not re-usable. That's the equivalent of the
| first stage you just saw getting caught
| throwaway48476 wrote:
| Shuttle SRB segments were fished from the ocean and
| refilled.
| baq wrote:
| Yeah but salt water makes it about as difficult as
| building from scratch.
| throwaway48476 wrote:
| Then why didn't they stop?
| JumpCrisscross wrote:
| > _why didn 't they stop?_
|
| They did [1].
|
| [1]
| https://en.m.wikipedia.org/wiki/Space_Shuttle_retirement
| altcognito wrote:
| Beyond the fact that they eventually did quit, the
| shuttle program was the public face of the US space
| program, and part of having more than one way to launch
| military stuff.
| adt2bt wrote:
| SRBs were in fact reusable.
| YoumuChan wrote:
| Economy of scale: starship can be "mass"-produced
|
| Material: stainless steel is much cheaper
|
| Percentage of reusability: boosters of shuttle cannot be
| reused, maintenance of shuttle itself is also very expensive
| (heat shields were pricey). whereas the starship stack has
| higher reuse percentage and allegedly cheaper to maintain.
| moffkalast wrote:
| The shuttle was not even reusable by any modern metric, the
| main tank was always expended, the boosters had to be
| recovered, fully disassembled and cleaned.
| noitpmeder wrote:
| This is significantly less expensive
| fragmede wrote:
| the space shuttle was "reusable". It had to be taken apart
| and meticulously cleaned and tested and basically had to be
| rebuilt after each flight, in a process called turnaround.
| SpaceX's rockets are much closer to what you'd consider
| reusable.
| usrusr wrote:
| I wonder how much of that difference is because the space
| shuttle was human rated from the start: F9 eventually got
| there, but only after plenty of "testing in production"
| with disposable payloads.
|
| The other big difference, an elephant in the room grade
| difference I think, is that SpaceX reliability was
| developed with memories of a reusable vehicle failing
| mostly due to turnaround costs and risks on everyone's
| minds. That clearly wasn't the case when the space shuttle
| was designed, they were the first and enjoyed the privilege
| of making all the beginner mistakes.
| WalterBright wrote:
| I had an email exchange with Homer Hickam, before SpaceX
| existed, where I remarked that the shuttle design looked
| like a giant kludge, and a winged reentry vehicle was a
| fundamentally bad design, for various reasons which I
| enumerated elsewhere in this thread.
|
| He emailed back that he agreed with my reasons and had
| argued that case with NASA in the early stages of the
| shuttle program.
|
| So NASA was aware of this at the time.
| mhh__ wrote:
| I was under the impression tha they also thought this
| themselves but got "persuaded" with the prospect of more
| money if it could handle certain payloads of use for
| defense?
| baq wrote:
| Shuttle was a jobs program just like the SLS is.
| moffkalast wrote:
| Yeah the right word is refurbishable, plus the main tank
| was not reused and the solid boosters got a salt water bath
| each launch.
| adt2bt wrote:
| Think of the word 'reusable' in this case as less a binary
| descriptor but more of a scale of reusability.
|
| Yes, both systems are reusable, but there are key differences
| in the refurbishment of the systems that partly explains the
| cost difference. It took more labor, resources and time to
| refurbish the shuttle. Also consider rapid reusability was a
| stretch goal when it was being designed, but we have come a
| loooong way since, spacex in particular has had it as a
| driving competitive differentiator for years now.
|
| Another big difference is that NASA post Cold War was a
| skilled jobs program, with an incentive to do distributed,
| high overhead work to appease their bosses (congress), while
| SpaceX has the opposite.
| cubefox wrote:
| > Yes, both systems are reusable, but there are key
| differences in the refurbishment of the systems that partly
| explains the cost difference. It took more labor, resources
| and time to refurbish the shuttle.
|
| Starship uses essentially the same ceramic heat shield
| tiles as the Space Shuttle, so the fact the Shuttle had so
| much trouble with refurbishment doesn't mean that SpaceX
| has solved these refurbishment issues with the Starship
| upper stage.
|
| Though the Starship lower stage, which contains the most
| expensive engines, doesn't have this problem. Since it
| doesn't need a heat shield. So partial reusability should
| be pretty realistic.
| timschmidt wrote:
| Shuttle's tiles were each unique. Starship is mostly clad
| with identical hexagonal tiles which can be mass produced
| and eventually refurbished by machine. A robot already
| welds on the tile fittings.
| BurningFrog wrote:
| That was 24,300 unique parts rather than 1!
| azernik wrote:
| The tiles are very similar; the attachment system is very
| different (a big part of why Shuttle's were a pain to
| maintain) and Starship's simple shape means most of the
| tiles are the same (the ridiculous number of SKUs was
| another factor in Shuttle TPS costs).
| credit_guy wrote:
| The main difference is that this is built by a private
| corporation who can't afford to throw money away, while the
| Space Shuttle was build by the government, and moreover it
| had to fulfill a number of conflicting requirements, and
| commercial profit was not one of them.
|
| But on a more technical level. I think the vertical landing
| is the main difference. Vertical landing was obviously known
| and done by NASA, this is how the lunar modules landed on the
| Moon. But doing it on Earth, with vehicles weighing hundreds
| of times more, I don't think the world had that technical
| readiness a few decades ago, when the space shuttle was
| designed.
|
| And another major difference is the mass manufacturing idea.
| From the start SpaceX planned for getting to mass manufacture
| its rockets. The Falcon rockets are much cheaper than any
| other alternatives even if you remove the reusability.
|
| Then it's the methane burning engines. This was pure old
| fashioned engineering progress. SpaceX's engines are miracles
| of rocket engineering. Aside from that, the fuel choice is
| extremely smart. Methane is better than all other fuels,
| except for hydrogen. Hydrogen was the fuel of the space
| shuttle, but it's very tricky to work with. It has very low
| volumetric density, so the tank of the space shuttle was
| absolutely humongous. Hydrogen needs to be stored at an
| absurdly low cryogenic temperature, so this adds to the
| complexity. And that tank was not reusable, so it adds to the
| cost.
| haspok wrote:
| Spacex might be a private company, but this project is
| funded by NASA, meaning the American taxpayer. Approved by
| a person whose last act was this approval before leaving
| NASA and joining Spacex (effectively putting money in their
| own pocket).
|
| It is also yet to be seen how Starship will ever be
| profitable (outside of spending government money), who is
| going to pay for those launches and for what purpose. Other
| than Starlink, of course.
| throwaway48476 wrote:
| The problem is that launch costs went down fast but
| satellite costs haven't gone down as fast and still have
| long development timelines. The other problem is the
| market for satellite services hasn't developed as fast as
| anticipated, except for starlink.
| baq wrote:
| Starlink for all intents and purposes is the market for
| satellites now. All the other launches are nice to have
| extras.
|
| Now personally I'm looking forward to NASA, ESA and JAXA
| to launch outer solar system probes like new horizons but
| with tons of fuel left in the tank to safely make orbit
| around there.
| XorNot wrote:
| Having enough lift capacity to take a shot at putting a
| pair of telescopes out far enough to exploit solar
| gravitational lensing to resolve exo-planet surfaces
| would be a hell of a thing. Orbital refueling would mean
| we could reasonably build something big enough to be able
| to boost out that far (would still take decades to
| arrive).
| cryptonector wrote:
| Isn't that 500 AU out?
| oceanplexian wrote:
| Starlink is predicted to have something like 6.6B in
| revenue. SpaceX isn't a rocket company they are an ISP
| that launches rockets.
| varjag wrote:
| Is that long term or this year? Because honestly 6.6B is
| not a lot for their scale of operations.
| cdash wrote:
| That is projections for this year only with a target
| closer to 10 billion revenue next year.
| mhandley wrote:
| Things can only be cheap if you mass produce them. That
| tends to require standardization of components, and
| inevitably standardized components are a compromise
| between requirements, where up until now, saving mass was
| a critical requirement. If you don't have to care nearly
| so much about mass and volume, then that opens up many
| avenues for much cheaper standard satellite components.
| tuatoru wrote:
| I'm disappointed that you _still_ can 't order ten
| cubesats from Shenzen Satellite Supply Co via AliExpress.
| ufmace wrote:
| The whole design process for them is based around
| launches being expensive and taking a long time to plan.
| It will be very interesting to see what happens when the
| whole process gets used to launches being relatively
| cheap and frequent. No need to spend years making sure
| the design is perfect and will definitely last a long
| time if you can launch a new one in a week if you make a
| mistake.
| Denvercoder9 wrote:
| > this project is funded by NASA
|
| Partially. They have a fixed-price contract to land
| humans on the Moon, and notably got that contract because
| they severely undercut the other bids and were the only
| bid that actually fit within the available budget: they
| bid $2.94B, while Blue Origin bid $5.99B and Dynetics
| $9.08B.
|
| That 3 billion is also much less than what they're
| spending on the project.
| zitterbewegung wrote:
| The purpose of funding SpaceX with taxpayer money is to
| make competitors that can launch rockets to space so that
| it is cheaper.
| mempko wrote:
| Exactly. Private companies like space X would not exist
| if NASA didn't deliberately make the market for Private
| space companies. That's what governments do, make
| markets.
| cryptonector wrote:
| Elon founded SpaceX w/o an expectation of subsidies.
| ben_w wrote:
| > Spacex might be a private company, but this project is
| funded by NASA, meaning the American taxpayer.
|
| So was the space shuttle, so that's not _a difference_
| between the launch costs of the two vehicles.
| throwaway4aday wrote:
| With a payload volume of 8m diameter by 22m height you
| could fit a James Webb size telescope inside with minimal
| folding. The sunshield (21.2 m by 14.2m) would only need
| to fold along one axis and the mirror (6.6 m) could be
| monolithic instead of having to fold, probably only
| requiring the mounting points for the primary and
| secondary to be hinged. This shouldn't be discounted
| because it makes telescope design much simpler and less
| expensive.
|
| It also allows for launching individual space station
| modules that have almost the same volume as the entire
| ISS in one launch.
|
| Their plans for refuelling on orbit with tanker versions
| of the starship open up the entire solar system to
| unmanned missions with much shorter timelines and much
| higher payload size and weight.
|
| The fact the entire system is re-usable will make it both
| cheaper and faster to use than any other launch system.
|
| All of this combined mean that it won't just be countries
| and space programs bidding for space on launches, it puts
| space within reach of many corporations and some private
| individuals. This isn't conjecture, it's already
| happening with the Falcon 9. Starship will make it even
| more accessible.
| foobarian wrote:
| > With a payload volume of 8m diameter by 22m height you
| could fit a James Webb size telescope inside with minimal
| folding.
|
| Of course, that means you could also fit a James Webb-
| folded telescope except make it a lot bigger :-)
| throwaway4aday wrote:
| Yes! that too.
| Earw0rm wrote:
| Probably need on-orbit refueling to work for that to
| happen, but they're working on it.
| bryanlarsen wrote:
| > but this project is funded by NASA
|
| About 10% funded by NASA. Starship is a >$10B program;
| SpaceX is getting $3B for Artemis of which >2/3 is for
| operational tasks and moon-specific stuff that SpaceX
| aren't relevant for SpaceX's goals of LEO and Mars.
| cryptonector wrote:
| The Artemis money could evaporate and Starship would
| still make commercial sense and likely be a successful
| product.
| mensetmanusman wrote:
| The federal government smartly invested in SpaceX after
| being sued by SpaceX to fix rigging (things what the
| system working looks like).
|
| Now taxpayers have a 10x return on investment.
| WalterBright wrote:
| > and commercial profit was not one of them
|
| But it's high cost was the end of it.
| cryptonector wrote:
| Its high cost would (should!) have killed it regardless,
| but its low reliability was going to be a huge problem
| too, and arguably it's the lack of reliability that
| finally killed it.
|
| The high cost should have killed the project before it
| ever flew, but that's not how governments behave.
| WalterBright wrote:
| In order to land as a glider, you'll need wings, landing
| gear, doors, rudder, stabilizer, flight controls,
| streamlining, all the structure needed to support it, and a
| heat shield for all of it. All that complexity has to work
| reliably, too.
|
| All of that adds tremendous weight, complexity, and cost.
| bamboozled wrote:
| What is all this rocketry doing for climate change if
| they're burning methane? Hopefully it's methane from
| landfills etc?
| credit_guy wrote:
| I did the math, and the impact is not negligible. One
| single launch releases the equivalent of 5000 tons of
| CO2. Elon wants to get to the point where there are
| thousands of Starships, each doing a few trips to orbits
| _per day_. That would be more than one millions launches
| per year, or more than 5 GT of CO2-equivalent. That 's
| about 10% of the worldwide emissions today.
| gedy wrote:
| If we actually get to that point, we'll eventually be
| doing a lot more activity and manufacturing off the Earth
| where the CO2 emissions don't matter.
| the8472 wrote:
| > Methane is better than all other fuels
|
| There are better fuels in terms of Isp and density. They
| have some downsides such as being corrosive or having
| highly toxic exhaust.
|
| https://x.com/ToughSf/status/1453391050681327622
| tuatoru wrote:
| Yeah, methane is kind of second best (or worse) in many
| parameters, but most importantly, it's cheap, abundant,
| and easily and safely storable and transportable, and it
| does the job.
| tim333 wrote:
| Also chosen as it may be possible to synthesize on Mars.
| inglor_cz wrote:
| Massive. The designers of Starship studiously avoided all the
| problems that made Space Shuttle expensive to refurbish:
|
| a. Cheaper, more durable material (stainless steel).
|
| b. Cheaper, easier to manufacture engines.
|
| c. Easier to use fuel (methane is much "tamer" than
| hydrogen).
|
| d. Standardized heat shield with much smaller requirements
| for manual work.
| _dain_ wrote:
| Manufacture and maintenance contracts for the Shuttle were
| deliberately spread out across many companies and states,
| especially in key congressional districts. It was a jobs
| programme; waste was a feature not a bug.
|
| Same thing for SLS.
| pfdietz wrote:
| More fundamentally, there _were_ contracts. SpaceX does
| things itself; there 's no legal friction internally. This
| gets back to the "Theory of the Firm" for why firms exist
| in the first place (transaction costs).
|
| The need to codify what work is to be done in contacts is
| antithetical to SpaceX's rapid development processes.
|
| https://en.wikipedia.org/wiki/Theory_of_the_firm
| pfdietz wrote:
| s/contacts/contracts/
| JumpCrisscross wrote:
| > _space shuttle was reusable_
|
| SpaceX builds vehicles. The Shuttle was "reusable" because
| they needed a term between the default for transportation
| capital expenditures ( _e.g._ trains, planes, cars and ships)
| and the modified missiles that defined post-War spaceflight.
| "Reusable" in the Shuttle's context meant months of
| specialist overhaul time and the cost of a Falcon 9 launch in
| SRB booster replacements alone [0].
|
| At the end of the day, in 2010, "the incremental cost per
| flight of the Space Shuttle was $409 million, or $14,186 per
| kilogram" [1]. ($591mm and $20,512 in 2024 dollars,
| respectively [2].) SpaceX's _prices_ per kg are around $3,170
| on Falcon 9 [3] and $1,520 for Falcon Heavy [4]. Starship
| should bring those costs below $1000.
|
| [0] https://forum.nasaspaceflight.com/index.php?topic=51959.0
|
| [1] https://en.m.wikipedia.org/wiki/Space_Shuttle_program
|
| [2] https://www.usinflationcalculator.com/
|
| [3] https://www.spacex.com/media/Capabilities&Services.pdf
| _LEO_
|
| [4] https://en.m.wikipedia.org/wiki/Falcon_Heavy _LEO,
| theoretical_
| vardump wrote:
| > Starship should bring those costs below $1000.
|
| It might even bring the costs below $100/kg.
| ben_w wrote:
| It might, but it's also at a scale where people can dust
| off the old plans for orbital rings and ask if this time
| the economics work out.
|
| (My guess is the economics are fine, but the politics
| would kill it on earth, so the moon or mars will get one,
| but that's just an interested amateur opinion).
| vardump wrote:
| Once you put something _big_ in the LEO, you 'll have to
| be able to boost its orbit indefinitely, because the
| orbit will otherwise slowly decay.
| DarmokJalad1701 wrote:
| That depends on how high the orbit is. If it is high
| enough, the decay will take centuries.
| ben_w wrote:
| IIRC, above something like geostationary they tend to
| decay _upwards_? Though the old orbital ring white paper
| wasn 't suggesting anything like that, this was an
| alternative to needing to go so high in the first place.
|
| (I may be misremembering or getting confused with a thing
| specific to tidal locking?)
| AdammadA wrote:
| I wonder if they could have an orbit high enough to move
| away from earth with some kind of drag cables dangling
| from them into low orbit to counter the outward movement.
| Would that work?
| dotnet00 wrote:
| You mean something like a skyhook?
| lucianbr wrote:
| The L in LEO means we're talking about orbits that are
| not very big.
| schiffern wrote:
| By definition, LEO extends up to 2,000 km. At that
| altitude orbital lifetimes can exceed 10,000 years.
|
| https://commons.wikimedia.org/wiki/File:Orbital_Debris_Li
| fet...
| ben_w wrote:
| Contiguous rings filling an entire orbit don't have much
| air resistance, and what little they do have is small in
| comparison to their momentum.
|
| But yes, eventually things decay.
| piombisallow wrote:
| If you have the infrastructure to build an orbital ring,
| you have the infrastructure to keep it supplied too
| pantalaimon wrote:
| There is some SciFi story about civilization collapsing
| and the survivors worrying that the sky will fall on them
| hidden in there.
| dyauspitr wrote:
| Gotta make the individual pieces small enough to mostly
| burn up completely on rentry.
| jaggederest wrote:
| Term of art for this is "design for demise", i.e. make
| everything of pieces small enough and materials ablative
| enough that there's less than 1 in 10k chance that any
| debris will survive to the surface.
|
| https://www.esa.int/Enabling_Support/Space_Engineering_Te
| chn...
| delichon wrote:
| Perhaps an advanced ancient civilization existed that
| kept the surface as a nature preserve and lived in an
| orbiting ring that shattered like safety glass on its
| demise and incinerated evidence of itself on reentry.
| Vecr wrote:
| Already exists, _Chasm City_ by Alastair Reynolds. They
| absolutely trash orbit by planning very badly and over-
| packing habitats.
| HarHarVeryFunny wrote:
| The Shuttle consisted of the shuttle (orbiter) itself, the
| external tank (not reusable), and the two boosters which
| could be reused after ocean recovery. The orbiter itself was
| slow and expensive to reuse since (among other things) all
| the heat shield tiles were inspected and 30-100 replaced
| between each launch. I don't know how much work was done to
| the engines between launches, but SpaceX's parts and cost
| reduction on the Raptor engine have to give it an advantage
| there.
|
| StarShip consists of the Super Heavy booster that we saw
| "caught" today, and the StarShip (orbiter) itself. Having the
| booster return to launch site vs requiring ocean recovery
| should potentially increase cadence and reduce cost of reuse.
| StarShip is also meant to be reusable, although it remains to
| be seen how that will pan out. On the previous flight there
| was burn through from inadequate heat shielding - maybe we'll
| see an improvement with today's vehicle. I'd expect SpaceX to
| iteratively arrive at a quicker and more cost effective
| orbiter reuse procedure than NASA had with the shuttle, but
| how quick remains to be seen. Of course they are planning
| many of these to go on one-way trips to Mars rather than
| being reused.
| cubefox wrote:
| > The orbiter itself was slow and expensive to reuse since
| (among other things) all the heat shield tiles were
| inspected and 30-100 replaced between each launch.
|
| Worth noting that Starship's heat shield is very similar to
| the one of the Shuttle. They actually got the manufacturing
| method from NASA.
| philistine wrote:
| That's why I remain very skeptical about the easy
| refurbishing of Starship. Initially, way back around
| 2016, the plan was to vent liquids to create a cushion
| around the ship. That sounded more easily reusable.
| cubefox wrote:
| Yeah. I think they originally planned to use ceramic
| tiles only for certain spots and still transpiration
| cooling for the rest. Then they fully switched to ceramic
| tiles. In an interview with Everyday Astronaut on
| YouTube, if I recall correctly, Elon Musk said they first
| believed the ceramic tiles to be lighter.
| bryanlarsen wrote:
| Starship is supposed to be fully & rapidly reusable. Neither
| adjective applies to the space shuttle.
| inemesitaffia wrote:
| Read the article "SpaceX flight Ops"
| alemanek wrote:
| Falcon 9 has already proven that partial reusability is
| economical. SpaceX has dominated the entire worldwide launch
| industry and their competitors are nation states with no need
| to make a profit.
|
| The difference is that they have already proven to be the
| lowest cost and most reliable launcher due to reuse. This is
| them lapping the industry with second stage reusability.
| fastball wrote:
| Shuttle itself was refurbishable, but not rapidly re-usable.
| It was also incredibly expensive to build and refurbish. A
| shuttle launch also utilized boosters that were not re-
| usable.
|
| Starship is supposed to be (and clearly well on the way to
| being) _fully rapidly re-usable_. That means all stages (in
| this case two) are re-usable, and that the capital and time
| required to get either stage flight ready again after a
| flight should be minimal.
|
| Said another way - it is cheaper for SpaceX to build an
| entirely new Starship + Booster than it was to refurbish a
| Shuttle between flights, by a factor of about 4x ($90M for a
| Starship+Booster / $400m for Shuttle refurb).
| fpoling wrote:
| The boosters for the Shuttle were reusable, but it turned
| out the cost of refurbishing them was similar if not higher
| than simply building new ones. Plus it contributed to the
| Challenger crash, see "Mr. Feynman Goes to Washington",
| https://calteches.library.caltech.edu/3570/1/Feynman.pdf
| dyauspitr wrote:
| The difference is only a small part- the shuttle itself- was
| reusable. The booster that put it into space was scrapped
| every time.
| ErneX wrote:
| The boosters were not (or at least not with the quick
| turnover and lower costs like the ones from SpaceX)
| shoxidizer wrote:
| You've got a lot of responses on the difference of
| reusability, but the shuttle was also more expensive because
| it had to carry a lot of capabilities with it every time. If
| you were launching a satellite, you were carrying along the
| crew compartment and a couple astronauts. If you were
| bringing a few astronauts to the space station, you brought a
| cargo bay. And in either circumstance, you brought big wings.
| Starship can be filled with all cargo. And if you're just
| changing crew on the ISS, you could... not use Starship and
| launch a Falcon 9 instead. One of the mission profiles
| required by the Air Force for the shuttle was that it be able
| to rendezvous with a satellite, put it in the cargo bay, and
| return to Earth, all under 2 orbits and along a path that
| avoided flying over the Soviet Union, which required a rather
| large turn in-atmosphere to make it back to landing on the
| west coast.
| dangus wrote:
| To answer this oversimplified question with a simple answer,
| the Space Shuttle couldn't be a more different vehicle than
| this one. It truly is a comparison between apples and
| oranges.
|
| Let's start with the fact that it was designed in the 1970's.
| If you had a Cadillac DeVille from 1970 it would get 8-12
| miles per gallon. Just the mere fact that the design is about
| 70 years old makes that vehicle too expensive to operate, and
| that's before we even start talking about other issues with
| the design (performance, safety, reliability, etc).
| modeless wrote:
| The Space Shuttle was not fully reusable as the biggest
| single part, the orange tank, was destroyed every time. But
| more importantly, the orbiter and boosters needed 2+ months
| of refurbishment/rebuilding after every flight.
|
| One of the design goals of Starship is for the booster and
| ship to relaunch with zero refurbishment. To literally land
| over the launchpad, refuel, and go back to orbit within hours
| without people even approaching them. The heat shield is the
| biggest risk to that goal IMO, and we saw today that it
| definitely sustained serious damage despite improvements. But
| if they ever get there then per-launch costs will be a tiny
| fraction of the Shuttle with 6x the payload.
| sobellian wrote:
| The majority of damage to shuttle's TPS apparently came from
| foam strikes from the external fuel tank. Superheavy's
| optimized profile certainly helps here, since there are no
| large cryogenic tanks hanging ominously over the TPS while
| being shaken violently by solid rocket boosters.
| ijustlovemath wrote:
| No one has answered with one of the biggest issues with the
| shuttle: each one was extremely custom. Every single heat
| shield tile was unique to a specific position and a specific
| shuttle. There were probably over a hundred million
| individual components in the Shuttle, and with many critical
| ones being custom, the time to refurbish it for a new launch
| was much longer.
|
| This is in contrast to something like the falcon, which has a
| very standardized mfg process and components, which allows
| for really rapid iteration
| cryptonector wrote:
| The shuttle wasn't fully reusable, just for starters. The
| boosters were reusable with a lot of refurbishment work. The
| center tank was expended every time. It was very expensive.
| Only five shuttles were ever made, which means that no effort
| was put into automation of production of engines etc.,
| everything was custom, and everything required great care to
| save the sunk costs.
| slashdave wrote:
| Early designs of the shuttle were fully reusable. That was
| quickly dropped due to costs and requirements. The final
| shuttle design was also unsafe.
| dools wrote:
| Because people are reflexively averse to government spending
| unless there's a billionaire making profits on the way
| through thanks to 100 years of academic capture by Austro-
| libertarian economists.
| interludead wrote:
| This opens up immense possibilities for exploration
| le-mark wrote:
| I'd love to see a probe catch and examine `Oumuamua.
|
| https://en.m.wikipedia.org/wiki/`Oumuamua
| autonomousErwin wrote:
| That was crazy, 50% of me thought as it was coming in, especially
| as it pitched towards the tower, "they've overcompensated and are
| going to bring the whole tower down" but they absolutely nailed
| it.
| phkahler wrote:
| Yeah but they did pass some flame down much of the tower.
| Pretty quick though, probably just cleaned it with fire.
| ivanjermakov wrote:
| Saving up those refurbishment costs, cleaning the tower ahead
| of time!
| foobarian wrote:
| Even without the catch step, I always feel like their boosters
| are coming down way too fast way too late, with engines
| reigniting startlingly close to surface. Never ceases to
| surprise me.
| hobofan wrote:
| Yeah, it also always catches me off guard how late they
| reignite, while at the same time I'm always surprised by how
| slow the liftoff is even though all the boosters are on full
| throttle. Of course both things make sense given the
| respective mass at both points in the process, but given that
| it looks like the same rocket from the outside, a bit
| unintuitive.
| mshockwave wrote:
| I have the same feeling watching Starship when the telemetry
| on the bottom right of the screen showing "0km" but landing
| burn hasn't started. Later did I know that it was meant to
| start the burn only a few hundreds _meters_ from the ground
| grecy wrote:
| Prior to today the only landings you've seen are Falcon 9,
| which has to do a "hoverslam" because it can't throttle low
| enough to actually hover.
|
| Even just one engine in minimum thrust would make the rocket
| go up when empty.. so the computer lights the engine at the
| precise right moment so it will have 0 velocity at 0
| altitude, then it cuts off the engine. "Hoverslam".
|
| The Starship booster is different, it can actually hover.
| lutorm wrote:
| Every moment your engines are burning at anything less than
| maximum thrust, you are wasting fuel. You want to relight as
| late as possible with as high thrust as possible for maximum
| efficiency. But that it actually works is nuts.
| Havoc wrote:
| Yeah it definitely looked sketchy for a sec but was probably
| fully as intended
| dmix wrote:
| Video of the catch
|
| > Mechazilla has caught the Super Heavy booster!
|
| https://x.com/spacex/status/1845442658397049011
| aaronharnly wrote:
| Naive question: I obviously expect there to be flames from the
| engines, but there were flames on the lower sides for quite a
| while after the catch - is that expected?
| thepasswordis wrote:
| My guess is that it's venting out the system pressure, and
| it's safer to burn it.
| sourcecodeplz wrote:
| who cares... they did it and it didn't burn up or destroy the
| platform. rest is just nitpicking
| swarnie wrote:
| Outside of maybe Boeing "who cares..." isn't a valid answer
| in engineering.
| panick21_ wrote:
| [flagged]
| ethbr1 wrote:
| It's an interesting engineering question, not a slight.
|
| Obviously the primary mission was successful, in spite of
| anomalies (good system design!), but people are and
| should be curious about this aspect.
| tonyarkles wrote:
| There's a bunch of people crapping on you who clearly
| haven't been through a flight test campaigns.
|
| 100% with you. The teams I've worked with would be
| celebrating and trying to figure out what's burning at
| the same time. And especially trying to figure out if
| there's anything that they need to do to collect evidence
| for that investigation (eg zooming the remote PTZ cameras
| in on specific areas or things like that)
| dang wrote:
| Please don't respond to a bad comment by breaking the
| site guidelines yourself. That only makes things worse.
|
| https://news.ycombinator.com/newsguidelines.html
| kiba wrote:
| It's a prototype.
| ben_w wrote:
| That's why it's not a catastrophe that something was
| unexpectedly on fire, not a reason to dismiss the
| question.
| jjk166 wrote:
| So the whole purpose of it is to identify issues to be
| resolved.
| Denvercoder9 wrote:
| > who cares...
|
| I bet SpaceX does. They've solved the big problems, now
| it's time to solve the small problems and make reuse a
| reality.
| haliskerbas wrote:
| Isn't this a forum of hackers caring about the news?
| Everyone seems excited here and that excitement naturally
| leads into curiosity for many who identify as hackers.
| ceejayoz wrote:
| You usually see some down near the engines after a Falcon 9
| landing.
|
| The vent out the side before touchdown didn't look right,
| though. Something blew, but non-critically.
| dotnet00 wrote:
| Probably not expected, but the nice thing is that they don't
| have to pull the vehicle off the bottom of the ocean to study
| what happened there.
| exitb wrote:
| Desirable? Probably not. Expected? Yeah. Especially given
| that is the was pretty unexpected to work on the first try.
| tankenmate wrote:
| It does look like venting, but on the Everyday Astronaut
| video feed it also looked like a COPV inside one of the
| strakes looked like it exploded as well.
| inglor_cz wrote:
| If not an intended vent, probably some methane leak. Given
| that they have the first stage intact, they will know exactly
| what happened very soon. Yet another advantage of having the
| rocket returned instead of sinking it in the ocean.
| generuso wrote:
| It is common for Starship prototypes to have uncontrolled
| fires, but it is obviously not a good thing.
|
| For example, prototype number 10 exploded 8 minutes after
| landing [1] because of a seemingly insignificant fire at the
| bottom.
|
| After today's flight there was a long lasting fire in the
| engine section, with occasional flaming pieces of plumbing
| raining down from the rocket. Examining the aftermath should
| help SpaceX to understand what improvements need to be made
| to prevent this from happening.
|
| [1] https://youtu.be/XOQkk3ojNfM?t=38346
| ls612 wrote:
| This same issue was common on early Falcon 9 landings and
| took a while to fully eliminate.
| mrandish wrote:
| This highlights another thing I love about watching
| SpaceX's unprecedented rate of progress. They're managing
| the complex balance of risk, learning, time and budget
| extremely well. I'm not an expert in the relevant domains
| but even I've noticed and appreciated that the typical
| SpaceX development test always manages to get big chunks of
| new data, while still having some notable things not quite
| working.
|
| It's an object lesson in rapid engineering development. If
| everything goes perfectly in a development test, it's a
| sign you're not moving fast enough (meaning not taking
| enough risk per increment to maximize learning). As
| valuable as Falcon, Starlink and Starship are, the biggest
| near-term value of SpaceX may be providing such a clear
| demonstration of well-executed "fail fast, learn fast"
| engineering that even politicians and bureaucrats can
| understand it.
| zitterbewegung wrote:
| They have mission goals which were achieved (booster was
| caught). Goals that they didn't think they could do (Starship
| being within the buoys). While there was flames and those
| could be dangerous you judge the mission based on the planned
| outcomes but they will try to eliminate the anomalies to
| improve the next mission while still achieving the goals.
| tempestn wrote:
| The thing is that no one is judging the mission based on
| this imperfection. It's just intellectual curiosity, which
| is a good thing. The comments that are getting down voted
| are all assuming some negative motive that just isn't
| present.
| lexicality wrote:
| It looked to me like the fire was on the fuel intake valves
| and if you watch carefully that area was scoured by the
| nozzle output when it was first slowing down so it probably
| blew through the shutoff valves or something
| rkagerer wrote:
| I'd love to see followup analysis of what that fire was all
| about.
| cryptonector wrote:
| In some of the views of the landing it's clear that the
| flames are from a methane vent. I.e., it's really not a
| problem.
| gizajob wrote:
| Amazing achievement.
| credit_guy wrote:
| I wonder what will happen when they get to 99% reliability?
| They clean up and rebuild the Mechazilla every once a hundred
| catches, on that occasion that one fails?
| bombcar wrote:
| I suspect there's already a whole "refurbishment" process for
| the crane even for non-reusable launches, and once it's
| working darn reliably, they can just have a bunch of them
| ready to go, and cycle once in a while.
| creer wrote:
| The next one is already mostly built and very different
| from this one. They move fast.
| bufo wrote:
| The plan is to have many, many Mechazillas.
| brianwawok wrote:
| I also expect if something fails a test in the way down you
| crash in the water rather than splat your catcher
| dotnet00 wrote:
| The booster aims towards the shore until the landing burn
| starts, only then does it swing towards the tower. So, for
| the most part, failures should mean that the booster safely
| crashes into the water.
| slashdave wrote:
| That, and redundancy. The amount of cash you save allows you
| to do that.
| ls612 wrote:
| They've landed over 300 Falcon boosters and haven't wrecked
| their barges yet I expect that this won't be a major issue.
| nomilk wrote:
| 10 minutes from 3h25m of this video shows launch and catch.
|
| Historic viewing :)
|
| https://www.youtube.com/watch?v=YC87WmFN_As&t=3h25m14s
| afh1 wrote:
| This angle is even more impressive IMO
| https://x.com/kimbal/status/1845451222750306344
| nilsherzig wrote:
| It's very impressive to see the buildings next to it, the
| original video lacks any sense of scale
| sourcecodeplz wrote:
| Damn what a time to be alive! Amazing
| teractiveodular wrote:
| It's difficult to overstate how important the milestone of
| catching the booster is. Now we have a reusable rocket an order
| of magnitude larger than anything we've had before, and the cost
| of kg to orbit just nosedived.
| HarHarVeryFunny wrote:
| I'm not sure how critical "catching" the booster is to
| reusability, but it does save weight by not needing legs for
| landing, and perhaps the booster suffers less stress this way?
|
| Note that the booster is not really being "caught" although
| this is the word it seems we're stuck with. It's really more
| like landing on the arms, since it throttles to a hover at that
| point.
| mshockwave wrote:
| I think saving weight is definitely one of the main issues,
| see those proportionally large legs on Falcon-9, I guess it
| simply doesn't scale on bigger vehicles like Starship / Heavy
| booster. Also, by catching the booster on site, they can even
| save the transportation and do the refurbishing on site, so
| even shorter turnaround time I guess.
| pfdietz wrote:
| Also, saving on damage to the landing pad.
| chasd00 wrote:
| That's a good point, they used the sprinklers on landing
| to mitigate damage to the pad and the booster was caught
| well off the ground.
| Denvercoder9 wrote:
| > I'm not sure how critical "catching" the booster is to
| reusability
|
| Not necessarily for reusability, but it helps significantly
| for rapid reusability: it eliminates the need to transport
| the booster from the landing site to the launch site. Given
| that it's 9m x 70m and weighs 270 tonnes, that's not an easy
| process.
| newsclues wrote:
| Efficiency and cost are the goals, reusability is just one
| way to do that. Moving big heavy things less is another.
| cryptonector wrote:
| > but it does save weight by not needing legs for landing
|
| That was the exact reason they went this way.
| shirro wrote:
| Second stage reuse seems the far more challenging problem.
| Other companies should have reusable boosters soon but if
| significant amounts of Starship continue to ablate on the way
| down they could be faced with a disposable Starship competing
| with smaller and cheaper second stages that are well sized for
| typical payloads. We already knew boosters can be flown back to
| launch sites reliably with high accuracy. We don't know if it
| is possible to make rapidly reusable thermal protection systems
| that can operate on an orbital vehicle of Starship's size until
| it is demonstrated.
| api wrote:
| Didn't they look at all kinds of ideas earlier like squirting
| some propellant or water out over the skin on the way down,
| and wasn't steel chosen for its thermal robustness? Did they
| get into the problem and realize it's a lot harder and
| abandon those things for tiles?
|
| Maybe they will have to sacrifice more payload mass for
| active or passive shielding or more fuel for powered
| deceleration. That would yield a less impressive lifter but
| with full reusability.
| chasd00 wrote:
| Yeah for rapid reusability tiles aren't going to work, too
| fragile. Iirc it was with a lot of reluctance they went
| with tiles and will have to make breakthroughs on the heat
| shielding to get where they want to be.
| cma wrote:
| Inspection might be easier with computer vision advances
| since the space shuttle.
| api wrote:
| Also with a saner design. The shuttle had a complicated
| shape with every tile being almost unique. It was nuts.
| rini17 wrote:
| They already plan refueling infrastructure in orbit. That
| would include stuff to "squirt" on the way down if
| necessary. If they can use one extra launch to reuse 5-10
| starships that might be interesting. Noone knows yet if
| it's actually needed.
| wolf550e wrote:
| They dropped transpiration cooling, at least for now.
| WalterBright wrote:
| Interestingly, the inside surface of a rocket nozzle is
| covered with tiny holes. Fuel is circulated in a jacket
| around the nozzle both to pre-heat the fuel and to cool the
| nozzle. Additional cooling of the nozzle comes from fuel
| leaking into the combustion chamber through those holes,
| carrying away the heat so it doesn't melt the nozzle. It's
| called boundary layer cooling.
|
| It was one of the technological breakthroughs of von
| Braun's team with the V2.
| philistine wrote:
| > Other companies should have reusable boosters soon
|
| You're way too optimistic. Starship will deliver commercial
| payloads, with SpaceX phasing out Falcon 9 outside of ISS
| launches, before anyone has a reusable Falcon 9 equivalent.
|
| It pains me to say this, but SpaceX is in a class all its
| own.
| thinkcontext wrote:
| The Chinese could have a reusable booster before then. One
| of their companies is doing 10 km hop tests.
| signatoremo wrote:
| SpaceX couldn't manage the first Falcon 9 landing until
| 2015. The first Falcon 9 reuse wasn't until 2018, so 3
| years to achieve reusability. The Chinese prototype
| hasn't yet succeeded at sub-orbital landing. I wouldn't
| be surprise if it'd take them longer than 3 years to have
| a reusable rocket. Starship would have been routine at
| that time.
|
| Blue Origin plans to launch New Glenn in a month, with
| landing planned. They are a wild card.
| jiggawatts wrote:
| I'm not _saying_ they stole the plans through industrial
| espionage, I'm just wiggling my eyebrows suggestively
| while glancing in the direction of the suspiciously
| similar looking booster.
| ls612 wrote:
| Is this the same company that had their booster fly into
| the air when they were trying to _static fire_ test it?
| jiggawatts wrote:
| They must have forgotten to steal the plans for the hold
| down clamps.
| dotnet00 wrote:
| New Glenn finally has flight hardware undergoing pre-flight
| testing. I think they're pretty likely to manage to fly in
| early/mid 2025, and they do aim to recover the booster in
| their first try.
| WalterBright wrote:
| Why does it pain you? Musk's SpaceX has produced several
| enormous advancements in space technology.
|
| SpaceX is one of the greatest, if not the greatest, private
| technology company in history.
| andrewstuart2 wrote:
| I think it pains some of us to say it because of the
| person Musk has turned out to be, which is the opposite
| direction I think many of us were hoping his character
| development would take him.
| WalterBright wrote:
| What terrible thing has Musk done?
| jiggawatts wrote:
| Supported Trump.
| WalterBright wrote:
| The Democrats have a sad history of denigrating Musk,
| which is likely why he changed from being a Democrat to a
| Republican.
| jiggawatts wrote:
| You don't spend that kind of money and risk alienating
| your entire customer base (and future workforce!) just
| because of a slight.
|
| Musk is getting something from Trump: most likely
| protection from some legal issue.
| WalterBright wrote:
| It was more than a slight. Biden pointedly ignored Tesla
| when conducting an EV summit and handing out subsidies.
| Then there was the FCC fiasco where the FCC snubbed
| Starlink.
| grey-area wrote:
| Supporting the openly fascist Donald Trump is a terrible
| thing.
| WalterBright wrote:
| You'll have to indict more than half of the country,
| then.
| chasd00 wrote:
| He likes what some people don't like. Truly, the world's
| greatest monster.
| pie420 wrote:
| no, he says retarded and cringe things on twitter, which
| is embarrassing for such a titan of industry.
| mensetmanusman wrote:
| Doesn't everyone know that people are like this, but
| those that put on a show as if they aren't like this are
| just putting on a show?
| ZeroGravitas wrote:
| Yeah, he's like a cross between Henry Ford and Werner Von
| Braun...
|
| and coincidentally he makes cars and rockets too!
| oldpersonintx wrote:
| > Why does it pain you?
|
| because Internet People feel they are in a existential
| struggle with anyone who disagrees with them even
| slightly
| asadotzler wrote:
| Wildly incorrect. New Glenn is already here.
| audunw wrote:
| I found Jeff's Bezos interview with everyday astronaut really
| illuminating on this topic.
|
| Supposedly they're working on both a reusable and cost
| optimised non-reusable second stage at the same time. And
| they don't really know yet which one will end up being
| cheaper.
|
| You also see this kind of thinking with Rocket Labs neutron
| rocket. Where they focus on making the reusable booster do
| more, while making the second stage smaller, cheaper and
| simpler.
|
| I think if it wasn't for the rocket engine this wouldn't be a
| question at all. The tank doesn't have much value. It's just
| a thin shell and probably a fraction of the cost of the fuel.
|
| So I'm thinking, perhaps the optimal solution is something
| like this: the bottom part of the second stage with the
| engines separates, and a small engine and fuel tanks places
| the engines in a stable orbit. The tank itself is deorbited
| and burns up.
|
| At some point later something like the Starship collects
| several second stage engines and deorbits them safely to be
| reused.
|
| Or perhaps just the engines can be immediately deorbited with
| an inflatable heat shield and parachutes.
| cryptonector wrote:
| > Second stage reuse seems the far more challenging problem.
|
| Sure, SpaceX has been doing first stage reuse for a long time
| now. But they have demonstrated landing the second stage
| successfully at sea twice now with the same sort of
| smoothness that they demonstrated once for the booster before
| they then caught the booster on the first real try.
|
| A partial list of unbelievably hard things that SpaceX has so
| far made seem easy: - building a rocket from
| scratch - landing Falcon 9 boosters - landing
| Falcon 9 boosters *reliably* - 3x weekly launch cadence
| (Falcon) - the bellyflop manoeuver - mass
| manufacturing(!) a rocket engine - catching the booster
| - simulated landings of the ship
|
| Catching the booster is really just like landing a Falcon 9
| booster w/o legs, but clearly much harder.
|
| Anyways, if they can do all those things then it's pretty
| clear that they can catch-land the ship.
|
| There's still a huge list of crazy-difficult things that
| SpaceX say they want to do that are hard to believe are
| possible, except for the fact that SpaceX has already done so
| many unbelievably difficult things already.
| stevage wrote:
| They're a long way from having a reusable super heavy booster.
| It's still copping a lot of damage on the landing.
| throwaway4aday wrote:
| true but don't forget this is test flight #5
| interludead wrote:
| It's a game change
| kvakkefly wrote:
| That was soooo good!
| redserk wrote:
| The SpaceX engineers are incredible for being able to pull this
| off.
| themgt wrote:
| NSF video:
| https://x.com/nasaspaceflight/status/1845442658203734384
|
| Truly incredible. A day for the history books.
| alecco wrote:
| > NSF is not affiliated with NASA, but the initials in the URL
| are used with permission from NASA.
| ghc wrote:
| Nothing could have prepared me for how that catch looked. I was
| sure the rocket was careening into the tower at the last second
| before it straightened out. The control algorithms must be
| incredible for the landing system to work within those small
| tolerances.
| starspangled wrote:
| That was one of the greatest things I've ever seen.
| marssaxman wrote:
| Literally brought me to tears, watching that happen.
| monkeydust wrote:
| Watched several times, amazing stuff.
|
| Had flashbacks to playing Jupiter Landing on the C64!
|
| https://en.m.wikipedia.org/wiki/Jupiter_Lander
|
| Edit: SpaceX should create a simple 'catch' the rocket game.
| Play in browser style. Just for kicks and marketing.
| miyuru wrote:
| > Edit: SpaceX should create a simple 'catch' the rocket
| game. Play in browser style. Just for kicks and marketing.
|
| there is, it was discussed in the FAA thread.
|
| https://news.ycombinator.com/item?id=41821220
| renewiltord wrote:
| This is a pretty fun game. Not so easy. Good job to the
| creator for having added some mechanics that make it work.
| dominicdoty wrote:
| Shameless plug for my own project with a similar bent - write
| your own lunar lander autopilot in browser
|
| lunar.unnecessarymodification.com
| demarq wrote:
| very fun got 51! with fuel limit + mass enabled.
| poorlyknit wrote:
| Very cool :) I got a good enough score in the basic
| scenario by playing around a bit but it would be cool if
| you could link some kind of tutorial (e.g. to a digital PID
| video or something like that).
| demarq wrote:
| so now managed to save 63% fuel, but score doesn't seem to
| take this into account (still 51)..
| sobani wrote:
| > SpaceX should create a simple 'catch' the rocket game. Play
| in browser style. Just for kicks and marketing.
|
| They did: https://starshipthegame.spacex.com/
| CodeWriter23 wrote:
| I succeeded with a High Score of -287!
| KORraN wrote:
| This one is not from SpaceX, but gives way more fun:
| https://mechazilla.io/
| HPsquared wrote:
| That's great, really shows how they are "threading a
| needle" on the control side of things.
| tails4e wrote:
| Felt special witnessing history, was delighted my kids and
| their friends all were glued to the TV for it also.
| dtquad wrote:
| MIMO and nonlinear control theories are probably some of the
| hardest topics in all of engineering. SpaceX control system
| also has to compensate for the fuel moving inside their rockets
| so the control algorithms probably involve some kind of fast
| numerical fluid simulation.
|
| Another interesting thing SpaceX is doing is to use consumer-
| grade chips in triple redundancy configurations instead of
| using $100,000+ radiation-hardened aerospace/defense grade
| chips.
| autonomousErwin wrote:
| I always thought the liquid sloshing would be one of the
| hardest to simulate (considering how chaotic fluid mechanics
| is). Interestingly, I think this caused the 2nd Falcon launch
| to fail (the LOX sloshing).
| JorgeGT wrote:
| It is difficult, but there are modeling approaches that
| work, such as VoF
| (https://en.wikipedia.org/wiki/Volume_of_fluid_method).
| Basically, in addition to velocity, pressure, temperature,
| etc., you store an additional scalar in each cell of your
| computational mesh representing the liquid's volume
| fraction. Then, you solve an additional equation to
| transport that scalar.
| s1291 wrote:
| Solving the Navier-Stokes equations numerically in 3D is
| very time-consuming, even on HPC clusters, not to mention
| the additional modeling required for multiphase flows.
| Your answer implies that the solutions are obtained
| almost instantaneously, which is not the case.
| nothercastle wrote:
| They probably pre solved a bunch of scenarios and
| interpolate between them known solutions
| j_maffe wrote:
| That usually doesn't work for chaotic systems.
| KeplerBoy wrote:
| Maybe the tank is just not a large hollow structure but
| contains fins/compartments/whatever to restrict the
| sloshing motion and it's not that big a contribution to
| the overall motion.
|
| If it's no stronger than a sudden wind gust, it's just
| something the controller has to be able to take care of
| without a heads-up.
| TowerTall wrote:
| That is how they build the tank in Formula One Racing
| (and probably many other race cars, I guess)
| kaonwarb wrote:
| These are indeed part of the solution and are known as
| baffles. They have risks of their own, e.g.:
| https://wccftech.com/baffling-baffles-musk-explains-why-
| spac...
| nuancebydefault wrote:
| In the first spacex rocket Musk thought that it was a
| good idea to not install baffles. He learned from
| experience that they are indeed needed.
| m4rtink wrote:
| I remember a very similar anecdote about Von Braun & the
| early Juno/Jupiter rockets - with someone pointing out
| issues with sloshing on a press conference & Von Braun
| brushing it off as insignificant.
|
| Then the next launch crashed due to slosh induced
| oscillation - and the one rocket after that had anti-
| slosh baffles. ;-)
| vocram wrote:
| That's how tanks in race cars are made. Another solution
| is fill the tank with some kind of sponge-like material.
| m4rtink wrote:
| That would be far too heavy in this case. :)
| 486sx33 wrote:
| Sometimes... the baffles break off, and then become
| surfboard projectiles inside the tank.
|
| More fluid dynamics
| krisoft wrote:
| I think the reason these kind of simulations are fast
| enough is because they are very coarse and approximate.
| Don't think of asking how exactly the foam swirls around
| the individual longerons, more like a very rough
| estimation of which side of the tank the liquid is
| slumped to. Remember it doesn't have to be "exact" just
| close enough to be useful.
|
| By their very nature model predictive controllers operate
| in a world where not everything is perfectly modelled.
| Engineers do their best and whatever is left is the
| "error" the controller is trying to deal with.
| Log_out_ wrote:
| Or you compute variations ahead of time and do a
| situation based lookup, hoing through loops if a
| situation ressembles another one.
| keepamovin wrote:
| Maybe they don't need to model the fluid dynamics, they
| just need to detect the mass movement / acceleration
| forces caused by it, and use those sensor inputs to
| inform a picture that's fed into their correction
| thursting.
|
| Sort of like how you can balance a few pitchers of beer
| on a tray in your hand by remaining aware of the weight,
| even when people remove one! hahaha :)
| m4rtink wrote:
| Still if there indeed is "free" mass moving about, you
| need to make sure your control inputs don't make it slosh
| harder, so you compensate for that, so it sloshes even
| harder, etc - basically avoiding oscilation. :)
| keepamovin wrote:
| Yeah..ah, control theory. Heh :)
| jjk166 wrote:
| They don't need to solve the Navier-Stokes equations,
| they don't care how the fluid is actually behaving, they
| just need to approximate how the mass is moving within a
| margin of error that the control system can handle.
| WalterBright wrote:
| If the computation is too difficult, another approach is
| build a test stand and try methods until it works.
|
| Which is why we use wind tunnels, for example.
| swader999 wrote:
| Wouldn't it burn most of the fuel to mitigate the effect?
| dtquad wrote:
| I think some Kerbel Space Program players have attempted to
| approximate the liquid sloshing as an inverted single or
| double pendulum problem inside the rocket that the control
| algorithm has to take into consideration in addition to the
| primary control of the rocket.
| sobellian wrote:
| At least for the retro-propulsive landing burn, I think the
| modeling problem is probably aided by the high G-forces
| that must keep the fuel very close to the bottom of the
| tank. Even before re-light the booster is falling near
| terminal velocity (I think?), so the fuel is likely sitting
| at the bottom.
|
| I think it's a huge problem when re-lighting the engines in
| orbit, though.
| chasd00 wrote:
| Iirc cold gas thrusters are used before ignition to
| provide some acceleration to force the fuel to the bottom
| of the tank.
| baq wrote:
| The technical term for that is 'ullage'.
|
| See also: https://en.wikipedia.org/wiki/Ullage_motor
| m4rtink wrote:
| Also IIRC the massive main tanks in Super Heavy should be
| basically empty at landing & the landings propelants come
| from a set of small header tabks that are near the
| central axis of the vehicle & arr completely full. This
| should reduce or even fully remove sloshing issues at
| landing time.
| dmitshur wrote:
| Has it been considered to spin the fuel via some centrifuge
| mechanism as a way to remove sloshing from the equation, or
| is that more complex/expensive/error-prone than just
| predicting it via simulation?
| m4rtink wrote:
| I'm thinking we will eventually end up with "active fuel
| management" techniques like this for in space vehicles.
|
| Bug tanks make sense there & they might not be always
| full. So I can imagine all kind of interesting ways you
| can work with the fuel in zero go to avoid not only slosh
| but also the need for ullage thrusters. Eq. some
| programmable nozzles using in-tank gas to nudge liquid
| fuel blobs to move in the right direction. Or even some
| nets or bags that herd in the fuel in the middle of the
| tank + prevent it from directly touching the side,
| reducing boil-off or refrigeration requirements. :)
| phkahler wrote:
| Maybe they just use pressure sensors to tell where the
| fluid is within the tank.
|
| Even a real-time simulation should have some measurements
| to self correct to some degree. Otherwise it'll diverge.
| macinjosh wrote:
| There wouldn't be a whole lot of fuel left by the time it's
| back to land so likely an irrelevant factor.
| bob1029 wrote:
| https://en.wikipedia.org/wiki/Model_predictive_control
|
| http://cse.lab.imtlucca.it/~bemporad/publications/papers/ecc.
| ..
| sidewndr46 wrote:
| how much liquid fuel is present when it lands? I assumed all
| the clouds it was giving off was it dumping fuel to make sure
| it was empty on landing
| sephamorr wrote:
| Less than 5% of a full load. Any extra fuel you brought to
| the edge of space and back is lost performance, so
| substantial efforts are made to minimize this lost mass
| fraction.
| jccooper wrote:
| That's probably venting of excess pressurants and/or an
| engine purge.
| arijo wrote:
| I never thought of using fluid dynamics in the rocket
| stabilization algorithm--maybe it's something that could be
| useful to prevent many of the accidents involving liquid-
| transport trucks
| alexpotato wrote:
| Reminds me of the early days of Google File System.
|
| They used trios of regular consumer grade disks/servers etc
| as a cluster and it looked like a single node.
|
| They had to replace a LOT of hardware but this was still
| cheaper than big iron industrial grades servers.
| moffkalast wrote:
| Interestingly cheap redundancy is also how life does things
| for the most part. Most biological organisms just replicate
| a lot to guarantee success, so it's clearly a good strategy
| and an efficient use of energy.
| szundi wrote:
| Efficient as in evolution or in business: you just need
| to be more efficient than most of the peers
| arijo wrote:
| > Another interesting thing SpaceX is doing is to use
| consumer-grade chips in triple redundancy configurations
| instead of using $100,000+ radiation-hardened
| aerospace/defense grade chips.
|
| This has been known in the high availability and safety
| systems industry for a while and a good book to learn these
| reliability engineering techniques is "Reliability Evaluation
| of Engineering Systems".
|
| The book is available on amazon: https://a.co/d/1nH824K
| wildzzz wrote:
| One downside of using non-rad hard parts is degradation
| from TID (gamma) and latch up effects. You can have chips
| monitoring other chips to reset whenever they latch up but
| TID is mostly permanent. The good thing is that TID in LEO,
| where SpaceX mostly operates, is relatively lower than GEO
| so they can get by with mostly commercial parts. It's not
| like the big defense contractors haven't figured out the
| same thing, they do fly stuff using commercial parts as
| well, they are just slower to adopt the same culture.
| SpaceX and the companies that built components using
| commercial parts are building the new-space industry.
| christophilus wrote:
| Could you surround your components with gamma-shielding
| materials and get away with off-the-shelf parts deeper in
| space?
| gafferongames wrote:
| "To block gamma rays completely, you need about 13.8 feet
| of water, 6.6 feet of concrete, or about 1.3 feet of
| lead."
|
| https://www.epa.gov/radiation/radiation-
| basics#:~:text=Gamma....
| arijo wrote:
| You don't need to block gamma radiation completely to
| increase the electronics reliability :)
|
| Maybe you could improve the system availability
| considerably by a bit of gamma radiation protection
| combined with some more parallelism of the components ..
| adastra22 wrote:
| Usually partial blockage is worse, because you end up
| with a spray of secondary particles instead of a single
| ray.
| arijo wrote:
| Makes intuitive sense, thanks for the insight.
|
| A second layer blockage for the secondary particles
| wouldn't have to be as dense or am I missing important
| physics?
|
| (I guess a lot of gamma radiation would still reach this
| second layer so please ignore my question :)
| adastra22 wrote:
| Keep adding layers until you get to 1.3 feet of lead and
| it'll work.
| arijo wrote:
| haha thanks for the correction - I was under the Turtles
| All the Way Down mindset :)
| numpad0 wrote:
| Isn't that more like how you make bombs than armors more
| effective - with backside spalling and secondary
| fragmentations?
| exe34 wrote:
| can you block a hemisphere? the other 2pi steradians are
| shielded by the earth...
| m4rtink wrote:
| Maybe the secondaries could be blocked by
| different/lighter materials ? Basically a Whipple Shield
| for radiation. :)
| christophilus wrote:
| A box with 1.3' walls seems doable, actually, depending
| on how small the chips are. Might still be cheaper and
| more effective than specialized chips. But I know
| nothing, so am probably wrong.
| xmprt wrote:
| Lead is extremely dense so carry 1.3' walls of lead is
| probably more expensive than just having more redundancy
| or using better quality chips.
| jazzyjackson wrote:
| I think the trouble is such a cube would weigh 12,400
| pounds (a sphere maybe more reasonable at 6,510lb -
| without any room for electronics inside)
|
| https://www.wolframalpha.com/input?i=+lead+cube+with+side
| +le...
| paledot wrote:
| Hah, beat me to the nerd snipe. Moreover, that sphere
| would cost $10k to make and, at a launch price of
| $1500/kg, cost $4.5 million to launch into orbit.
| bboygravity wrote:
| The aim for the launch price of the entire rocket is to
| be around 5 million (once it's fully re-usable and in
| production). Basically the price of fuel and maintenance.
|
| So something might be off with your assumption of 1500
| usd / kg.
| m4rtink wrote:
| IIRC the CPUs are much less susceptible to damage when
| powered-off ? So have a bunch of them in cold standby or
| even as additional pluggable modules on missions with
| humans on board & swap to good ones when needed? :)
| piyh wrote:
| More water in orbit sounds like a good idea to me
| persnickety wrote:
| Can it even be blocked completely? Every layer of
| material geometrically reduces the proportion of rays
| going through. Or am I wrong about that?
| Filligree wrote:
| No, that's correct. Of course there's still some level of
| reduction beyond which the gamma rays don't matter, but
| where you want to place it is somewhat arbitrary.
| jiggawatts wrote:
| Just put the electronics in the middle of the header
| tank.
| jacobn wrote:
| Would they need to be blocked completely? Maybe a much
| thinner shielding would still produce a significant
| benefit?
|
| (Though likely not of course ;)
| mttch wrote:
| High energy gammas have a relatively low cross section,
| most are going to pass right through the chip. If you add
| a too little shielding, or don't layer shielding
| appropriately you are going to stop more gammas but
| produce lower energy x-rays from the shielding, which
| have a higher cross section, potentially increasing your
| chip dose.
| WalterBright wrote:
| In reading Musk's biography,
|
| "Hollman also found that creativity got him a long way.
| He discovered, for example, that changing the seals on
| some readily available car wash valves made them good
| enough to be used with rocket fuel."
|
| "Elon Musk" by Vance pg 123
| WalterBright wrote:
| Aviation pioneered the use of redundancy in order to
| survive failures.
|
| The Fukushima and Deepwater Horizon disasters show that
| this knowledge has not penetrated other industries.
| michaelt wrote:
| Plenty of industries know about redundancy.
|
| But it turns out, it doesn't matter how many redundant
| backup diesel generators you've got if a 45-foot wave
| comes along and they're _all_ left underwater.
| eecc wrote:
| ... and you put all of them in the basement :/
| nmca wrote:
| Thank you very much for the reference!
| m4rtink wrote:
| From an article for this I remember one more interesting
| side effects of this approach - the flight computer ends up
| as a generic x86/ARM board that the engineers can just have
| on their desk during development. Previously the dev boards
| would use the same rad hard chips and would be as expensive
| and scarse as flight hardware, resulting in much harder
| development & engineers having much less experience with
| the real hardware.
| prox wrote:
| Just as a note, Space Engineers has a mod that accounts for
| fuel in the tanks and also various orbital mods. If one feels
| inclined to try it for themselves ;)
| serf wrote:
| as someone who absolutely loves SE -- please don't.
|
| the orbital and planetary mechanics kind of suck. They're
| meant to provide a decent 'arcade realism' for the sake of
| player/player interactions and pvp/pve.
|
| if you want to experience fuel slosh/weight during a
| vertical ascent/descent go with kerbal. It models a lot of
| that stuff _without_ mods -- and mods can make the model
| even more accurate.
| wildzzz wrote:
| I spent 2 semesters covering controls and I barely felt like
| I learned anything.
| WalterBright wrote:
| Reliability is not based on a system that cannot fail. It is
| based on a system that can survive failure.
| szundi wrote:
| ... or cannot fail
| mrdoops wrote:
| The canonical paper on handling software failures:
| https://erlang.org/download/armstrong_thesis_2003.pdf
| WalterBright wrote:
| There's much more to it than the programming language.
|
| Algorithms can be faulty as well.
| mlyle wrote:
| > There's much more to it than the programming language.
|
| Which was never claimed.
|
| That paper is a little bit about Erlang and a whole lot
| about OTP and other methodology and design technique.
|
| It is still, very much "the paper" for distributed
| systems, though its applicability to this particular
| problem is limited.
| mlsu wrote:
| I know MPC takes a LOT of compute power. It's not like a
| finely tuned PID loop or even a cascade of PID loops,
| computationally.
|
| Does anyone know (or have educated speculation on) what kind
| of hardware is running these algorithms? Like, do they have a
| linux machine that's running the control loops? Are we
| talking megabytes, gigabytes of SRAM?
|
| I would think no -- you would definitely need hard real time
| for something like this. But my only experience with real
| time systems is in tiny MCUs with kb of SRAM. That's
| definitely too small for a controller like this.
|
| Really curious about the nuts and bolts of this.
| mlyle wrote:
| MPC doesn't need to take a ton of compute power. It all
| comes down to how sophisticated the underlying model is.
| You can have a MPC with 20 variables and run it at multiple
| kilohertz on a tiny microcontroller.
|
| When you build something like this, you're torn between
| having a big model that represents _everything_ and a
| smaller model that is easier to validate and reason about.
| Based on simulation, you might go for a smaller model that
| "knows" to stay away from operating areas where hidden
| variables (like really complicated tank slosh) invalidate
| the small model.
|
| I doubt the actual control loop is too much processing, but
| it's certainly possible to build controllers with SDRAM,
| millions of variables of state, and hard realtime
| processing, though I wouldn't build it on top of preempt-
| rt. ;)
| bgnn wrote:
| It would be a real time OS running it for sure. Which one I
| don't know.
| erikerikson wrote:
| I have been told by people who worked on them that you get
| radiation hardened aerospace/defence grade chips by backing
| off the clock speed about 20% to give signal stabilization
| slightly longer time. I can understand the population being
| confused about this but industry being confused seems to have
| more to do with regulatory capture and beaurocratic moats
| which SpaceX does seem to be bypassing.
| mensetmanusman wrote:
| You also have to add massive amounts (relatively) of static
| sink by approaches like 'silicon on insulator' to prevent
| energetic electrons from hopping into the transistor layer.
| m4rtink wrote:
| I'm sure there are many hardening processes - from the
| modified COTS parts, all the way to presumably much more
| expensive custom substrates like:
| https://en.wikipedia.org/wiki/Silicon_on_sapphire
| macawfish wrote:
| People don't realize how powerful applied math (especially in
| the areas you've mentioned) has become. Same tools can be
| applied to people in the ad tech/social media.
| schiffern wrote:
| >probably involve some kind of fast numerical fluid
| simulation
|
| Sometimes even a simple approach can work. On Apollo they
| developed (at the time cutting-edge) passive RC filter
| networks, to avoid the control system "exciting" the rocket
| at frequencies of the slosh/bend/torsion modes.
|
| https://ntrs.nasa.gov/api/citations/19700023342/downloads/19.
| .. (search for "slosh" or "shaping network")
| gcanyon wrote:
| > control system also has to compensate for the fuel moving
| inside their rockets
|
| My stepfather worked as a programmer on the Apollo program,
| and the thing he always talked about as his biggest
| accomplishment was working on the "slosh problem" -- so yeah,
| props to the SpaceX team for managing that landing. And props
| to my stepdad for managing it on hardware that was... a
| billion times less capable? :-)
| kbmr wrote:
| Did he get a chance to see any of the recent SpaceX
| accomplishments?
| 3abiton wrote:
| > MIMO and nonlinear control theories are probably some of
| the hardest topics in all of engineering.
|
| I am curious but clueless about these problems, can you
| expand more?
| mataslauzadis wrote:
| Google is a good place to start.
| https://en.wikibooks.org/wiki/Control_Systems/MIMO_Systems
| jatins wrote:
| timestamp for "catch" is around 40:00 for those curious
| blackeyeblitzar wrote:
| When Musk first proposed this, I thought he was crazy. It
| seemed like something a school boy would draw up. Now I think
| this will become routine and forgettable after a few more
| successes. Is there a word for that - something out of fiction
| becoming mundane?
| api wrote:
| I thought it was plausible given the accuracy of F9 landings,
| though I still wonder how it will work at scale if one
| failure destroys the landing site. That could ruin the cost
| benefits.
|
| Where his vision hit a lot of speed bumps is second stage
| reusability. Starship is a beautiful second stage to throw in
| the ocean. They'll probably get it landing but the heat tiles
| will require a lot of refurbishment between flights. They're
| going to have to figure something else out.
| DiggyJohnson wrote:
| I really don't think it will ruin the cost benefit as much
| as you suggest, especially when they have multiple sites
| and multiple locations. It wound be catastrophic, but they
| are presumably building Tower like the rest of their
| hardware, and every time they launch it represents a $100M
| saving compared to the competition.
| ericcumbee wrote:
| It took months to more than a year to repair shuttle's
| heatshield in some cases. SpaceX replaced the entirety of
| the heatshield with a new design and a new ablative
| underlayment in a matter of weeks. I suspect they will be
| able to do it even quicker with design and process
| improvements. Small scale repairs of the heatshield between
| flights probably wont be all that big of a deal.
| cryptonector wrote:
| I'm expecting that SpaceX will have lots of towers, not
| just one (currently) or 3 or 4 (under way). It won't just
| be for redundancy. The duty cycle of a tower might simply
| not allow for the cadence that SpaceX wants to maintain.
| With Falcon 9 they currently have a 3x weekly launch
| cadence (which is unbelievable enough). With full
| reusability they might be able to get to daily and better
| cadence, so if the duty cycle of one tower does not support
| that (I assume right now it does not) then they'll need
| more towers.
| ninetyninenine wrote:
| This happened with LLMs in a big way. Basically humanity
| surpassed some kind of AI milestone and we zoomed past the
| turing test in a big way. But thanks to social media everyone
| is sort of rolling their eyes at it.
| drexlspivey wrote:
| The booster was falling at 4500 Km/h 30 seconds before the
| catch with 2-3% fuel left. How is that amount of fuel remotely
| enough to stop the downward momentum?
| stetrain wrote:
| Because the rocket weighs a small fraction of what it did at
| launch, specifically because it only has 2-3% fuel left.
|
| Fuel is the vast majority of the vehicle weight at launch,
| kind of like an empty vs full can of soda.
| justin66 wrote:
| The atmosphere does its bit to slow down the booster as
| well. It'd be interesting to see a plot of the power output
| over time on reentry but I've always assumed the motors
| aren't doing a lot of work other than keeping the booster
| stable, until the very end.
| stetrain wrote:
| Yes, for most of the booster return it's 'gliding' with
| the rocket engines completely shut down.
|
| They ignite a subset of engines just a few seconds before
| landing for the final slowdown and maneuvering.
|
| Edit: here is a video from further away that shows the
| rocket gliding in under control of the grid fins before
| the engines light and execute the final landing maneuver:
|
| https://x.com/shaunmmaguire/status/1845444890764644694
| justin66 wrote:
| Super heavy probably makes certain aspects (unrelated to
| the tower catching the booster) of landing much easier,
| by virtue of its greater mass. Timing with the Falcon 9
| was always essential, because the minimum thrust (with
| one motor, throttled all the way back) of one of the
| engines was enough that if you left the motor running,
| the booster would start to rise. Time the beginning of
| the final burn incorrectly and you had a real problem,
| with the booster either crashing or rising at the end
| and... then crashing, but with Super Heavy, it might
| simply be a matter of having to compute a slightly
| different sequence for shutting off the engines.
|
| They sure made it _look_ easy...
| nordsieck wrote:
| > Yes, for most of the booster return it's 'gliding' with
| the rocket engines completely shut down.
|
| Watching the video, it looked like the bottom of the
| rocket was glowing hot, but the engines were cool. I
| imagine that means they were probably running some amount
| of methane through the engine bells to cool them.
| HarHarVeryFunny wrote:
| Yeah, but even without fuel the booster weighs 200 tons.
| It's pretty wild to have 200 tons of steel incoming at
| supersonic speed, then nailing a gentle pinpoint landing
| like that !
| chedabob wrote:
| It weighs about 10% of what it did at liftoff, but half of
| the engines fire to slow it down.
|
| Also I don't think the telemetry on the feed is that
| accurate, so with all of the atmospheric braking, it was
| probably going a bit slower than the 1200km/h at engine
| reignition.
| magicalhippo wrote:
| First off, the booster was going about 1250 km/h when it
| started its landing burn, it relied purely on drag to get it
| slowed down to that speed.
|
| Going by the telemetry of the seconds before the landing burn
| and noting the speed vs time, it seems drag was around 40
| m/s^2 when it was going at around 3000 km/h. Since drag
| depends on velocity squared though, it had reduced to just
| above 10 m/s^2 just before the engines lit at 1250 km/h, and
| so would quickly become negligible once the engines lit.
|
| Going by Wikipedia, the Super Heavy[1] has 3400000 kg of fuel
| at launch, so 3% of that is about 102000 kg. For the landing
| burn, it used 13 Raptor v3 engines[2] to scrub speed. Each
| Raptor flows about 650 kg/s max, so 3% fuel is enough for
| about 12 seconds for the 13 engines.
|
| The empty mass of the Super Heavy is about 275000 kg, so
| about 377000 kg before the landing burn with 3% fuel.
|
| Using the sea-level vs vacuum performance of the Raptor v2
| engines, one can estimate that each Raptor v3 produces about
| 2.45 NM of force at sea-level. So 13 of them would produce
| about 31.85 MN of force.
|
| Using Newton's second law, F=ma, this gives an initial
| deceleration of about 84 m/s^2 and about 104 m/s^2 when
| empty. If we do a rough spreadsheet integration, we get that
| a burn of roughly 4 seconds is needed to scrub the speed
| assuming no other forces.
|
| Now, comparing this with reality, the full 13 engines were
| lit for a little over 5 seconds.
|
| In my simplified calculations I was assuming full throttle
| the whole way, which obviously isn't realistic, and I also
| assumed 3% fuel. So over all I think that's a pretty decent
| estimation.
|
| [1]: https://en.wikipedia.org/wiki/SpaceX_Super_Heavy#Engines
|
| [2]: https://en.wikipedia.org/wiki/SpaceX_Raptor
| rsync wrote:
| "... Super Heavy[1] has 3400000 kg of fuel at launch ..."
|
| So, 34M kg of fuel has to be burned (in this booster alone)
| to facilitate a flight ... and I see that the propellant is
| CH4 / LOX[1].
|
| Burning methane is much, much better than simply releasing
| methane but the release becomes CO2 instead ...
|
| What is the back-of-the-envelope conversion of 34M kg CH4
| vs., for instance, 34M kg of kerosene/JP ?
|
| [1]
| https://en.wikipedia.org/wiki/SpaceX_Super_Heavy#Engines
| CrazyStat wrote:
| 3.4 million, not 34 million. And that includes the weight
| of the liquid oxygen, which is heavier than the methane.
| ylere wrote:
| Methane has 28% more energy per kg than kerosene and also
| produces slightly less CO2 (2.75kg CO2/kg burned vs 3.00
| for kerosene) when burned [1]. SpaceX uses a 78:22 LOX to
| CH4 ratio, so for 34M kg of fuel burned, 20.57M kg of CO2
| are produced (34x0.22x2.75).
|
| [1] https://www.engineeringtoolbox.com/co2-emission-
| fuels-d_1085... [2]
| https://x.com/elonmusk/status/1298426245991063554?lang=en
| aw1621107 wrote:
| Somewhat tangential, but as far as rocket fuels go energy
| per volume is also an important metric to consider. It's
| one of the (several) reasons hydrogen isn't quite as good
| for rockets in practice as it is in theory - while
| hydrogen has tons of energy per unit mass (120-142 MJ/kg
| for hydrogen vs. 50-55 MJ/kg for methane and 43.1-46.2
| MJ/kg), it has a far lower density (70.85 kg/m3 vs. 422.8
| kg/m3 for liquid methane and 820 kg/m3 for kerosene). As
| a result, you need quite a bit more tankage for a given
| amount of energy from hydrogen compared to what
| methane/kerosene requires.
|
| IIRC there's a tradeoff between efficiency and thrust as
| well. Heavier fuels aren't quite as energy-efficient, but
| it's easier for them to develop a lot of thrust, which is
| important for the initial stages of launch. If I'm
| remembering events described in _Ignition!_ correctly
| this led to "thrust density" being something that was
| optimized for - to the point that there were experiments
| with mixing mercury into the fuel!
|
| [0]: https://world-nuclear.org/information-library/facts-
| and-figu...
|
| [1]: https://en.wikipedia.org/wiki/Kerosene
| Yacovlewis wrote:
| What kind of work do you do that you're able to understand
| this stuff? Genuinely curious. I'm way beyond my depth
| trying to follow
| r3d0c wrote:
| this is ap hs physics or uni 1st year physics
| magicalhippo wrote:
| Just a programmer, though been interested in physics
| since I was a teen and did take a bachelor degree in
| simulation (mainly physics).
|
| Long ago though so rusty, $dayjob doesn't involve any
| advanced math at all.
|
| edit: To expand, the "rough spreadsheet integration" was
| just the Euler method[1] assuming a constant
| acceleration. So v(t+dt) = v(t) + a *
| dt
|
| The acceleration comes from F=ma as mentioned, where F is
| the force of the engines (Newtons), m is the mass of the
| rocket (kg) and a is the acceleration (m/s^2). Solving
| for a we get a = F/m and we get v(t+dt)
| = v(t) + F/m(t) * dt
|
| To make things easy I assumed the weight of the rocket
| was constant at each timestep, but if we take dt to be
| small enough it's a decent enough approximation. For each
| timestep I also updated the mass using the estimated mass
| flow: m(t+dt) = m(t) - 650 * dt
|
| I started with m(0) = 377000 kg, v(0) = 1250 km/h = 347
| m/s, and a constant -31850000 N force from the engines.
|
| Using dt = 0.1 seconds, I got almost exactly 4 seconds
| until the velocity reached zero.
|
| [1]: https://en.wikipedia.org/wiki/Euler_method
| martythemaniak wrote:
| That's excellent work, only nit is I think these were not
| the v3 raptors. I think they're just now starting
| production of those, so they still have a bunch of earlier
| ones they need to use up in these early test flights. This
| actually makes your calculation more accurate, as earlier
| versions will need a slightly longer burn time.
| magicalhippo wrote:
| Ah, good catch, I must have misread the Wikipedia page. I
| misread that they were included in the rocket in August.
| Reading the Raptor page more closely I also see that the
| 2.75 MN of the Raptor V3 are supposed to be at sea-level.
|
| Anyway, plugging in the Raptor V2 thrust numbers the
| approximation increases to 4.25 seconds. This is in line
| with the thrust I used for the V3 being ~8% higher than
| the V2 thrust figures.
| jjk166 wrote:
| Note that the energy of 3% of the propellant (~100 GJ) could
| theoretically get the empty booster (100,000 kg) to a little
| over 5000 km/h if properly applied.
| Torkel wrote:
| I thought the same, screamed out "ouch that doesn't look good!"
| right before the catch.
|
| The last part of the live stream they showed footage from a
| different angle and there it didn't look too bad though! For
| sure controlled.
|
| Scott Manley put out a tweet that they went down towards a non-
| tower position until they were at three engine controlled burn,
| and only then did the side shift.
| brcmthrowaway wrote:
| Do the control algorithms use AI?
| arijo wrote:
| Actually this is a good question - there's a lot of control
| engineering research on Data-Driven Control Systems.
|
| Check Steve Brunton youtube channel, he is one of the leaders
| in this area:
| https://youtu.be/gb_C9LcjDSI?si=xUjqUZ9-0MIFohX6
| ThouYS wrote:
| If I had to bet, I would bet against it. Boston Dynamics for
| example, for the longest time, didn't use anything other than
| Model-Predictive Control. Only recently have they started
| using RL
| lutorm wrote:
| No. Way too hard to validate.
| shellfishgene wrote:
| The simulation they show at 21 min into the video is almost
| exactly like it happend in the end, to it seems it went
| perfectly as planned.
| pj_mukh wrote:
| I know the control algorithms are the mind-blowing part here
| but,
|
| does anyone have any literature about how the Rocket localized
| itself with respect to the chopstick arms? It must've been some
| combination of GPS and Radar pings to the arms?
|
| And then the onboard IMU to make sure it hits it straight.
| ThouYS wrote:
| super good question, especially with all the tilting
| involved, which would make visual servoing difficult. Maybe
| some form of beacons on the ground?
| cdash wrote:
| Could just be differential/rtk GPS. You can get incredible
| precision with that.
| shellfishgene wrote:
| From the control point of view, isn't this exactly the same
| as F9 landing on a pad, except the pad is virtual, floating
| in between the chopsticks and the ground? Or course one
| difference is that the approach needs to be from the correct
| direction.
| m4rtink wrote:
| I seems to remember some article mentioning the Falcon 9
| using radar (+ presumably other sensors) & even having a
| landing site map uploaded (mainly for the return to launch
| site scenarios) with prioritized exclusion zones in case of
| a landing failure.
| varenc wrote:
| Great question! Could just be Real-Time Kinematic (RTK) GPS
| like someone mentioned. Essentially the landing arms know
| their position very precisely and they measure the tiny
| errors in GPS data, and send that correction data live to the
| rocket in real-time as it's landing. Once the rocket gets
| very very close it could also just be using vision systems to
| zero-in on exactly where the chopsticks are.
|
| To speculate more, they could also be using something like
| ultra-wide band positioning. This relies on the same time-of-
| flight principle as GPS but instead of using satellites in
| orbit to provide the precise time information you rely on
| various nearby ground stations. Would only be useful right at
| the final approach, the last couple hundred meters, but it's
| another way they could get very very precise position
| information. (fun fact: Ultra Wide band positioning is also
| how iPhones can locate AirTags with centimeter accuracy)
| stetrain wrote:
| Here's a video from a farther vantage point that gives a better
| perspective on the landing process:
|
| https://x.com/shaunmmaguire/status/1845444890764644694
| gcanyon wrote:
| That's amazing footage, and you're right about the
| perspective: from the official feed the distances seem
| compressed compared to what we see in this footage.
| jccooper wrote:
| There's also a very impressive sensor and actuator story.
| slashdave wrote:
| Yes, indeed. But I will add that the sheer size of the rocket
| helps in this regard. I think it is rather hard to appreciate
| the massive scale of the feat by watching videos.
| mrweasel wrote:
| A clip from some news program popped up on YouTube, just a two
| minutes clip of the catch, I was convinced that it was
| reversed. The fact that this is possible, that they made it
| work is nothing short of amazing.
| Zealotux wrote:
| Uuuh the first stream on YouTube was Musk giving a speech, so I
| was waiting for the launch but turns out it was on another
| stream? So I just missed the whole thing, great.
| sourcecodeplz wrote:
| They don't do lives on youtube, those are scammers. it is
| always on x.com
| Zealotux wrote:
| Well it shows like SpaceX on mobile with 150k viewers, maybe
| YouTube could use some brain power to fix that.
| dotnet00 wrote:
| This has been going on for many years now, YouTube doesn't
| do anything about it.
| lupusreal wrote:
| Youtube is an incompetent organization. I've seen it take
| them nearly 48 hours to restore channels stolen by scammers
| to their rightful owners (all the while allowing the crypto
| scammers to continue streaming.)
| panick21_ wrote:
| Youtube simply doesn't care about their platform being used
| for scams. There are very simply very basic things they
| could do, but they simply don't.
| acheron wrote:
| Sorry, too busy selling ads.
| bearjaws wrote:
| Would be great if I could stream to my Chromecast or AppleTV
| from X without using airplay streaming my whole browser...
| panick21_ wrote:
| There were multiple streams on youtube who rebroadcast that
| you can use.
| jdminhbg wrote:
| There used to be a Twitter AppleTV app and I recently saw
| an X app for TV platforms has been brought back, but I
| don't know if the AppleTV version is out yet.
|
| Of course I'd rather they just stream to YouTube in 4K.
| thepasswordis wrote:
| Youtube has a terrible problem with scammers. I don't know why
| they don't do anything about this.
| hggigg wrote:
| There was an AI crypto scam channel. Musk is so scammy that it
| looked feasible and was shared widely by the looks.
| inemesitaffia wrote:
| https://twitter.com/i/broadcasts/1RDGlyognOgJL
|
| Here. Or try Space Affairs on YouTube
| mensetmanusman wrote:
| Those are deep fake crypto scams that YouTube does not pull
| down. My father was scammed by one for over $2000.
|
| The older we get, the likelihood that we get scammed approaches
| one. Be weary.
| belter wrote:
| Everyday Astronaut Stream: https://youtu.be/pIKI7y3DTXk
| ceejayoz wrote:
| That was craaaaaaaazy!
| sekai wrote:
| Magnificent, it's hard to image what we'll be able to do once
| these do roundtrips daily. For those are not aware, that booster
| is 71 m (233 ft) tall!
| paulryanrogers wrote:
| Improvements that make space flight more sustainable are
| welcome ... unless that means an order of magnitude more
| pollution in a less controllable form, like emissions. [Due to
| more frequent flights]
|
| Daily trips to space likely also mean more debris in space and
| falling to earth.
|
| I hope there is a balance that includes the lives of people
| near these sites and all of us sharing the same atmosphere.
| timeon wrote:
| I hope this is not going to be used for 'Earth point A ->
| Earth point B' travel.
| modeless wrote:
| SpaceX proposed it but I doubt there is any chance of this
| architecture ever achieving the airliner-level reliability
| needed for people to accept routine Earth-to-Earth
| passenger service. That's several levels beyond what you'd
| need to fly astronauts.
|
| Maybe a future architecture with more redundancy could get
| there someday.
| joko42 wrote:
| Humanity has reached a milestone.
| qwertox wrote:
| Congratulations to those working at SpaceX!
| delichon wrote:
| I would like to shake the hands of the steeley eyed rocket men
| and women who just landed a skyscraper with centimeter precision.
| Respect.
|
| This one's for you. Hit it Perry.
| https://www.youtube.com/watch?v=_VJlHWESyLI
| melodyogonna wrote:
| THEY REALLY CAUGHT IT!
| Yacovlewis wrote:
| Seems impossible honestly. Like the Jetsons
| gadders wrote:
| It still blows my mind how the landings are more exciting than
| the launches.
| bombcar wrote:
| I'm completely mind-blown that not only can they do this, but
| we get 1080p video for almost the whole time.
|
| What cameras do they have that can look at something 30 KM up
| in the air that well?
| throwaway48476 wrote:
| At one time they were using gopros.
| generuso wrote:
| Usually it is a small telescope on a nice motorized mount
| weighing a ton. NASA had several of those around Cape
| Canaveral [1].
|
| [1] https://www.youtube.com/watch?v=xig3sL_rRH8
| yonatan8070 wrote:
| The thing that impresses me even more is the kinds of cameras
| they mount on the rocket. How do they shield it from all the
| heat and debris with a material that's optically clear?
| ceejayoz wrote:
| They put it in places the heat and debris don't go.
| jjk166 wrote:
| Sapphire glass windows: they're good for up to 2000 C,
| mechanically strong and chemically resistant, and
| remarkably cheap.
| cynicalpeace wrote:
| "Incredible!" in the voice of my 3 year old who just saw it :)
| ptek wrote:
| Very inspiring, glad I woke up to watch it. Congratulations to
| the SpaceX team. This is what competition looks like. It's funny
| how last decade SpaceX had to sue the government to get more
| launches.
| XorNot wrote:
| The FAA needs more funding at this point. They're not staffed
| for the rate of launch requests which commercial space has
| grown too.
| bombcar wrote:
| We're going to need a dedicated FSA (federal space agency) at
| this rate, which should do most of the heavy lifting (ha) for
| the FAA and just use them for NOTAMs and TFRs.
| mkoubaa wrote:
| What makes you think the issue is funding?
| renewiltord wrote:
| The great conceit of government is that if something gets
| money when it is slow, that it will get faster as more money
| is given.
| WalterBright wrote:
| Socialism: when it fails, provide more funding. When it
| succeeds, cut funding.
|
| Business: when it fails, cut off the funding. When it
| succeeds, increase the funding.
| systemvoltage wrote:
| Need to remove regulations instead and fast track SpaceX.
|
| Every fucking time we don't need to increase the size of the
| Government. It only gets bigger. Never smaller.
| dawnerd wrote:
| No, launching big heavy explosive things into space
| shouldn't have fewer regulations. That's insane to think
| they should be able to just do it without much oversight.
| tomschlick wrote:
| Sure the safety part of it is something that should be
| verified before launch. But when they are launching
| multiple of these things and the variables are all mostly
| the same you don't need to do the same analysis over and
| over again.
|
| A prime example is the environmental impact stuff. They
| have already done that multiple times. Nothing really
| changed. If it succeed and doesn't blow up the impact is
| X, if it blows up the impact is Y. Yet these approvals
| take weeks and months.
|
| There are also multiple agencies that put their foot
| down. Famously fish and wildlife was worried starship
| would crash in the water and hit a shark/whale. No
| seriously. https://youtu.be/kS8G5D9fg3g?t=21
|
| Then there is the story that at Vandenburg air base, they
| had to strap a seal to a board and play rocket noises
| through headphones to see if it was distressed. Keep in
| mind Vandenburg has been a military rocket launch site
| for decades. But only now when its SpaceX do these
| agencies put up road blocks.
| https://www.youtube.com/watch?v=3SvJP5wfN4k
| ceejayoz wrote:
| > Keep in mind Vandenburg has been a military rocket
| launch site for decades.
|
| Not one of which ever returned to base with a sonic boom.
|
| I assure you, the folks who tried to kill goats via
| mental powers and staring at them have required weirder
| tests than the seal.
| tacticalturtle wrote:
| Isn't this exactly what happened with Boeing, where the FAA
| delegated its authority, on the assumption that Boeing knew
| what it was doing?
| dmix wrote:
| Regulations probably are not going to fix the rot that's
| inside Boeing. It's like putting water in groundhog
| tunnels, clamp down on one area and it will pop up
| somewhere else.
|
| They need to die off and get replaced by better
| competition when they mess up. And their market
| centralization ground to a halt instead of encouraged by
| the gov because of jobs and total risk aversion.
| mensetmanusman wrote:
| Boeing is publicly funded though, which means crazy
| incentives take over that are out of whack.
| derektank wrote:
| If by the size of government you mean the budget, there
| have been multiple instances of the government shrinking.
| As a percent of GDP the 90s saw cuts to federal spending,
| the 2011 sequestration saw a drop in spending even in
| nominal terms, and obviously the end of WW2 saw a massive
| collapse in government spending and the end of multiple
| different programs
| chasd00 wrote:
| More money would make the situation worse. They need
| competent leadership. Everyone like to just say "add more
| money" because it means no actual operational change to the
| status quo.
| acd10j wrote:
| You are right they are already trying to slow SpaceX as
| much as possible. More people in their hands more people
| finding ways to decelerate SpaceX
| atrus wrote:
| Hardly, the FAA is handing permits out the instant the
| mandated waiting time is up. They couldn't go faster
| without a _literal_ act of congress.
| TrapLord_Rhodo wrote:
| It's not a mandated "Waiting time". It's the max amount
| of time that they have to respond. And they wait until
| the very last day.
| gamblor956 wrote:
| The FAA already has competent leadership and staff. They
| don't have the budget to handle the increasing number of
| tasks they have been given to manage.
|
| The FAA manages _more_ flights and space launch operations
| than it did in the 1980s, when it had a budget more than
| quadruple the size.
|
| To put it bluntly: you get what you pay for.
| nmca wrote:
| You get what you incentivise, not what you pay for.
| mensetmanusman wrote:
| Yeah in my area govt. officials can be incentivized to
| say no to prove they are doing the job. Adds massive
| amounts of delay.
| whimsicalism wrote:
| perhaps we need less thorough reviews
| whimsicalism wrote:
| Not sure why this is downvoted.
|
| Our risk-to-regulatory oversight cost benefit analysis
| seems _extremely off_ - we overregulate small things that
| do not have large-scale meaningful impact while basically
| grandfather in stuff like depleting the Great Salt Lake,
| coal emissions, etc. which have _vastly less_ regulatory $
| spend per environmental impact.
|
| Ideally, if we could quantify all environmental impacts
| into a single number (ie. CO2 emissions but also wildlife
| impact, etc.), the $/impact spent across different fields
| would be equal.
|
| Currently, however, we are likely spending 100x+ on a per-
| impact basis on SpaceX regulation.
| coding123 wrote:
| Or dismantled, lol
| creer wrote:
| It seemed to not be FAA here, but the several other agencies
| that all had 60 days to respond. FAA fast-tracked it but
| couldn't fast track it past the other guys' 60 day allowed
| time.
| blackeyeblitzar wrote:
| Well that may still continue to happen. The wonderful and
| competent state of California is literally trying to block
| SpaceX launches over Musk's constitutionally protected
| political speech:
|
| https://www.politico.com/news/2024/10/10/california-reject-m...
|
| I cannot remember a more explicit case of authoritarian
| government abuse in a developed nation in recent memory, and
| it's especially infuriating given SpaceX and Musk are one of
| the most important and innovative companies and leaders of all
| time. No other country would think to look at such
| accomplishments and try to undermine themselves through petty
| politics and lawfare.
| blisterpeanuts wrote:
| It is a state commission composed of political appointees.
| It's unlikely it has the jurisdiction over Vandenberg to ban
| any activities, except when such activities violate state
| environmental laws. Even then, the federal government might
| be able to override them. It will be interesting to see what
| comes of this.
|
| Ideally, the commission will withdraw its objections and
| allow the launches; SpaceX obviously chose this site both for
| its proximity to the Pacific Ocean and for redundancy in case
| of poor weather in Florida (like this past week for example).
| blackeyeblitzar wrote:
| It has jurisdiction over Vandenberg for private launches,
| and there is debate over what counts as private versus
| federal. However, regardless of possible environmental
| concerns, they've already explicitly said they're targeting
| SpaceX because of Musk's political speech, which is morally
| reprehensible and also illegal per the constitution.
| neodymiumphish wrote:
| Can the federal government override them if the launches
| are purely commercial. Presumably that would be the case
| eventually, so I think it's something that needs to
| addressed sooner.
| SalmoShalazar wrote:
| I don't understand how this is a constitutional violation
| like you claim. Let's pretend he posted something absurd on
| Twitter for arguments sake, like "I'm going to use my rockets
| to kill every endangered bird on every California beach", do
| you think that should not be considered when evaluating the
| request for more launches?
| WalterBright wrote:
| California officials reject more SpaceX launches, with some
| citing Musk's X posts
|
| https://twitter.com/shellenberger/status/1845131546501734440...
| cryptonector wrote:
| That's madness. And unconstitutional.
| WalterBright wrote:
| Musk tweeted that he's filing a lawsuit Tuesday morning.
| mensetmanusman wrote:
| It's funny how much illegal stuff gets done by leadership.
| Sue to fix. Lawyers always win.
| mlindner wrote:
| The California Coastal Commission has no authority over a
| Federal (Military) launch range so there's no need for real
| concern. Yes using people's personal opinions for denial is
| illegal, but it's moot regardless. So I'm not sure SpaceX
| could sue for any damages.
| cdash wrote:
| They don't actually have any jurisdiction in this case.
| Launches from Vandendberg are from a military base and while
| they do try to work with the California commission they
| ultimately are the ones that decide what does and does not
| get launched.
| baq wrote:
| Congratulations. This is a Sputnik-level event, opening a new era
| in the history of civilization. Amazing.
| tekla wrote:
| The catch somehow absolutely demolished the amazing FH dual
| landing
|
| Holy shit. I almost had a heart attack when it looked like the
| booster was about to slowly careen into the tower
| TacticalCoder wrote:
| > I almost had a heart attack when it looked like the booster
| was about to slowly careen into the tower
|
| Same but it looks more dramatic on the feed we all got: on
| other vids the angle is different and although close it doesn't
| look it's going to crash into the tower.
|
| Still: feels pretty close.
| ryzvonusef wrote:
| First attempt!
|
| I can't believe what i just saw!
| zamadatix wrote:
| SpaceX has done it again! (defying status quo, not the catch :p)
| themgt wrote:
| NSF video:
| https://x.com/nasaspaceflight/status/1845442658203734384
| bearjaws wrote:
| Couldn't watch the livestream on X because it was erroring out.
| We live in a world where you can't stream a video or Chromecast
| on X but you can catch a damn rocket...
| dylan604 wrote:
| X has proven time and time again that it just cannot handle
| live feeds well.
| doug_durham wrote:
| I wouldn't bother with X. There were dozens of YouTube channels
| with the live feed.
| isbvhodnvemrwvn wrote:
| Live scams too.
| anonzzzies wrote:
| That was impressive.
| ETH_start wrote:
| SpaceX's Falcon 9 and Falcon Heavy have already revolutionized
| the space industry with their reusable first stage boosters and
| rocket engines. This advance in rocket design has resulted in the
| cost to launch one kilogram of payload to orbit from
| approximately $15,000 in the pre-SpaceX era, to around $1,400
| with the Falcon Heavy. This graph shows the incredible impact of
| SpaceX on the volume of rocket launches, with an exponential rise
| in recent years:
|
| https://ourworldindata.org/grapher/yearly-number-of-objects-...
|
| With Starship, SpaceX is striving to make rockets fully reusable,
| which, if they succeed, will transform human civilization by
| radically reducing launch costs and enabling large-scale space
| exploration and industry. The kinds of possibilities this opens
| up include economically viable permanent lunar bases, Mars
| colonization, and revolutionary industries like asteroid mining.
| dogma1138 wrote:
| When KSP becomes reality, 275 tons falling from space caught by
| some metal struts...
| travisporter wrote:
| Ryan Hansen had an incredible (although unofficial) 3d modeling
| video of the mechanism. https://m.youtube.com/watch?v=ub6HdADut50
| cam72cam wrote:
| Absolutely incredible achievement, I'm still shaking!
| renewiltord wrote:
| This is amazing. What an incredible technological feat!
| tayloramurphy wrote:
| This got me as excited as the original Falcon 9 landing in 2016!
| Now I got to share this with my kids! So incredible...
| Gud wrote:
| One of the biggest steps forward in the space industry since the
| first landing of Falcon 9.
|
| Great success!!
| grecy wrote:
| Happy Birthday! SpaceX lit a mighty big candle for you :)
| fragmede wrote:
| basically they transfer equipment from the rocket to the landing
| tower so that the rocket can be lighter which is why they have to
| catch the rocket instead of the rocket landing by itself.
| ungreased0675 wrote:
| Wow, that's amazing. Didn't think something like that would be
| possible.
| ftio wrote:
| What an incredible achievement. Huge congratulations to the team
| at SpaceX! Still have chills.
|
| Anyone know whether the fire toward the bottom of the booster
| during/after the catch is normal?
| 1970-01-01 wrote:
| Landing from space during sunrise while your rocket is on fire is
| as dramatic as it gets!
| bloopernova wrote:
| Giddy and crying.
|
| I turned 50 yesterday and it feels a bit like the future I
| dreamed of as a child.
| Yacovlewis wrote:
| This made me happy
| DarmokJalad1701 wrote:
| Right on target, next to their buoy! Insane achievement!
| pfdietz wrote:
| At a buoy, SpaceX.
| ryzvonusef wrote:
| the starship hit the target!
| t1234s wrote:
| Do they recover whats left of the ship from the Indian Ocean?
| eqvinox wrote:
| They can probably go fishing, but anything that sunk is gonna
| stay sunk. That ocean is not shallow, and deep submarine
| operations are _expensive_ ...
| dotnet00 wrote:
| They did pull the bottom of the previous booster out. On the
| webcast they mentioned adjusting the landing maneuver for the
| ship to be a bit softer in case they decide to recover it
| too.
| Klathmon wrote:
| The previous booster landed in the golf of Mexico.
|
| This starship landed in the Indian ocean a bit west of
| Australia, it's like 3x deeper.
| eqvinox wrote:
| | That.
|
| For extra context: that "3x deeper" makes costs seriously
| explode. People do know how to engineer for that depth,
| but it's a lot of effort and there's pretty much no
| commercial market. For shallower stuff there's oil rigs,
| deep-sea cables, seafloor mining, even just tourism...
| but at some point it just peters out and only research
| vessels tackle the depth.
|
| (source: friend of mine works at a UK university doing
| deep-sea vehicles)
| RaoulP wrote:
| >(source: friend of mine works at a UK university doing
| deep-sea vehicles)
|
| As in he works on their development? That sounds
| exciting, do you have something like the name of one of
| the vehicles?
| t1234s wrote:
| Do they worry about any issues of the debris winding up in
| the hands of China or Russia? I would imagine the raptor
| engines are mostly intact.
| rapsey wrote:
| You think there are Russian submarines in the gulf of
| mexico?
| eqvinox wrote:
| They splashed down in the Indian Ocean, not the Gulf of
| Mexico.
|
| Also noone mentioned submarines, debris can just float
| and drift around (sometimes even at some depth below the
| surface).
| Denvercoder9 wrote:
| Starship landed in the Indian Ocean, not the Gulf of
| Mexico.
| perihelions wrote:
| I mean, yes [0]. It's probably the main reason SpaceX
| went to effort to recover [1] all the engines of the
| previous booster (IFT-4), which landed in accessible,
| shallow water in the Gulf of Mexico. The Raptor engines
| hold valuable secrets, particularly to China who are
| trying to clone a lot of SpaceX things.
|
| The CIA did something very similar to this in the Cold
| War [2], though they used a boat instead of a submarine.
|
| [0] https://en.wikipedia.org/wiki/Akula-
| class_submarine#Operatio... ( _" In August 2012, the news
| media reported that another Akula-class submarine
| operated in the Gulf of Mexico purportedly undetected for
| over a month, sparking controversy within U.S. military
| and political circles..."_)
|
| [1] https://old.reddit.com/r/SpaceXLounge/comments/1fvdek
| t/more_... ( _" More images from B11 recovery + new info
| "26 of the Raptors have been recovered but they are
| trying to get all 33"_)
|
| [2] https://en.wikipedia.org/wiki/Project_Azorian
| phkahler wrote:
| Was the explosion intentional? I thought they were hoping
| it would float for recovery but if not I makes sense to
| sink it.
| renewiltord wrote:
| Do they have the ability? Russia couldn't get Kursk back.
| Not clear they could even do it if we left it there.
| eqvinox wrote:
| It's more of a financial question, do you want to shell
| out for some chance at it. And Russia and China can build
| their own engines, SpaceX is _very good_ but not like _a
| century ahead good_.
|
| (If anything, I'd be more worried about North Korea or
| Pakistan getting their hands on stuff...)
|
| Either way the risk is the shit that's left floating, if
| they don't fish it out it'll randomly wash up in
| Madagascar or so...
| skrebbel wrote:
| Can someone explain to me why this is more impressive than
| landing the rocket? To a layman like me, it looks very similar -
| the thing looks just like a rocket but without a pointy tip, and
| on the way down I don't understand why difference that matters.
|
| (I mean I still think it's mind blowing, because I think landing
| a rocket is also mind blowing)
| jq-r wrote:
| From what I understand, it reduces the turnover dramatically.
| In theory the booster should be refuelled, new second stage
| mounted on top and ready to go for another flight. So could cut
| down from weeks to days/hours. That's significant.
| Denvercoder9 wrote:
| It is a rocket. The biggest difference with the Falcon 9 first
| stage is that this one is about 6 times as big (diameter of 9m
| vs 3.7m), and that catching it with the tower requires a much
| higher precision in landing location. The drone ships that
| Falcon 9 lands on are about 90 x 50 meter. To catch it with the
| tower, they need to be accurate to within a few meters.
|
| The big advantage of catching it with the tower is that it'll
| (eventually) allow them to put another Starship on top, refuel
| and launch again within hours, as opposed to the weeks it
| currently takes for Falcon 9.
| HarHarVeryFunny wrote:
| The critical differences between Falcon 9 first stage and the
| Starship booster is that Starship booster lands using 3
| engines rather than 1, and can throttle them down much
| further. 3 vs 1 gives Starship more directional control for
| precise landing (critical for this "catch" maneuver), and
| throttling allows it to hover, as it does right before the
| "catch".
| Denvercoder9 wrote:
| Falcon 9 also lands using 3 engines on its most demanding
| missions. The throttling is definitely an advantage.
| xcskier56 wrote:
| But as far as I know, one Merlin engine produces more
| thrust than the empty booster weighs which means they
| have to time things perfectly to get to zero velocity
| exactly at the ground.
|
| Super heavy can hover and even go down by throttling down
| more. This gives them more control for the landing and
| don't have to time it exactly perfectly
| skrebbel wrote:
| Thanks!
| wwarek wrote:
| It's more precise than landing on the ground, there is
| coordination with the tower required, it is way bigger than
| Falcon 9.
|
| This video goes into details pretty well:
| https://m.youtube.com/watch?v=OYvWYp0--bQ&t=832s
| linuxfan2718 wrote:
| This method doesn't require landing legs on the rocket,
| allowing their weight to be used for payload instead
| MattRix wrote:
| It's also already on the tower that it launches from, which
| drastically reduces the expense and complexity of setting it
| up for its next launch, making it easier and faster to reuse.
| inglor_cz wrote:
| To expand on this, landing legs of Falcon 9 weigh two tons.
| Landing legs of SuperHeavy booster would have to be even more
| formidable.
|
| Which means that the weight savings are nontrivial with the
| "catch the rocket!" landing method.
| throwaway4aday wrote:
| The tower is also how they plan to perform maintenance and re-
| staging for another launch. The tower can place it back on the
| launch structure or lower it down to the ground if it needs to
| be transported back to an enclosure for extensive repairs but a
| lot of work is just done with it at the tower. I imagine the
| goal is to eventually get to an automated system that catches
| the booster, inspects it for damage, clears it for relaunch,
| positions it on the launch structure, grabs another Sharship
| second stage and stacks it and then refuels the whole system
| and launches as soon as possible.
|
| Plus it's really big https://images-
| bonnier.imgix.net/files/ill/production/Starsh...
| stetrain wrote:
| This booster is significantly larger than anything landed on an
| orbital launch before. Here is a size comparison, previous
| largest landed orbital rocket stage is the SpaceX Falcon 9
| (three of them launch together as Falcon Heavy) on the left.
| Starship is on the right.
|
| https://upload.wikimedia.org/wikipedia/commons/7/7b/SuperHea...
|
| Landing via tower catch versus on a pad is advantageous because
| the weight of adding retractable landing legs to such a large
| rocket would be significant.
| skrebbel wrote:
| Thanks!
| creer wrote:
| (1) Much larger than any previous rocket landing, (2) This
| rocket carried no landing gear (more efficient - landing gear
| is heavy), (3) This rocket landed right back at the place it
| needs to be to launch again - right on its launch tower - which
| in a routine situation might make it much faster to prepare it
| for the next relaunch. (4) It's yet another step in control
| prowess - impressive in itself.
| creer wrote:
| I must say though "right on its launch tower" is fun and
| all...
|
| but things would have to get pretty extreme in the "routine"
| dimension for that to be very useful. If there are 20 first
| stages and 5 land/launch towers, for a first stage that only
| spends an hour in flight in between inspections.... well are
| you going to keep them parked on a scarce launch tower for
| maintenance? The towers with fill/launch infrastructure (such
| as reinforced concrete, fuel tanks, cold filling system,
| deluge water system) become the bottleneck. It's more likely
| then that the 1st stage lands, is safed, then is taken a
| couple hundred yards away for inspection and maintenance
| while the next in line is moved to be stacked for the next
| launch. The inspection / maintenance would have to be truly
| minimal (think airliner) to keep it right there on its own
| relaunch tower.
|
| "No landing gear" is more key, compared to Falcon 9 - because
| of the effort toward minimal launch cost.
| throw4950sh06 wrote:
| > The inspection / maintenance would have to be truly
| minimal (think airliner) to keep it right there on its own
| relaunch tower.
|
| That's what they are aiming for, eventually.
| ErneX wrote:
| This one seems way harder than the others which land on legs
| and on a relatively larger circular landing pad, this one needs
| to nail the tower and its arms.
| h_tbob wrote:
| I think landing a booster is just as impressive. It's just that
| nobody's done this before, so it's exciting! Plus it's a lot
| bigger and part of a fully reusable config which has huge
| implications for space travel.
| banku wrote:
| This is incredible!
| systemvoltage wrote:
| Closeup of chopsticks as they were catching the booster, best
| clip from Everyday Astronaut's livestream:
| https://x.com/kagurazakimoto/status/1845447451592765820
| renewiltord wrote:
| The SpaceX clip is better
| https://x.com/spacex/status/1845442658397049011?s=46
| systemvoltage wrote:
| Better than both, NSF's stream:
| https://x.com/nasaspaceflight/status/1845442658203734384
| renewiltord wrote:
| It genuinely was. Thanks for that!
| systemvoltage wrote:
| Insane!
| nomilk wrote:
| I'd never considered a 70m tall chunk of mostly metal "agile",
| but the way it's controlled into the arms so precisely is
| something to behold.
| systemvoltage wrote:
| Do you know what the entire booster is hanging off of? It
| can't be the fins. How is the load transferred to the arms?
| SAI_Peregrinus wrote:
| The grid fins are what it's hanging off of.
| systemvoltage wrote:
| https://x.com/marionawfal/status/1845351598874120662
|
| I dug into it, found this clip. Elon says that it's those
| two tiny knubs! Saw a few pictures and yes, I confirm,
| it's not the grid fins.
| grecy wrote:
| The booster landed on "pins" that are structural load
| points and designed to support it's weight.
|
| Here is a brilliant profile shot looking down one of the
| "arms" after the catch today, you can clearly see it
| resting on the "pins", not the grid fins.
|
| https://www.reddit.com/media?url=https%3A%2F%2Fi.redd.it%2F
| 7...
|
| They also use those "pins" to raise/lower it with a crane
| when they need to during construction and during transport
| to the launch tower. It's the primary mode of lifting the
| thing
| bunabhucan wrote:
| There are two lifting points on opposite sides just below
| the fins.
| olalonde wrote:
| Anyone knows how the landing is guided? Is it just really precise
| GPS/altimeter or does it use computer vision?
| pfdietz wrote:
| I'd imagine a combination of inertial and GPS, combined with a
| Kalman filter. Inertial handles short term estimation; GPS
| correcting drift in the inertial system. But they could roll in
| other information sources at the end.
| imglorp wrote:
| For the centimeterish precision needed to hover into the
| chopsticks, they also have the opportunity to use signals
| from the tower area for final alignment. I'm thinking riding
| a beam like aviation ILS. Just speculating but it would be
| easy to implement.
|
| Optical/camera alignment is probably out of the question due
| to fire and smoke.
| pfdietz wrote:
| The arms themselves could have sensors on them. Inductive
| loops sensing the presence of the stainless steel
| structure?
|
| Also, I doubt centimeter scale precision would be needed;
| the arms have some compliance in them, I'm sure, as well as
| the ability to control how far in they swing.
| mt_ wrote:
| I would bet in the traditional sensors.
| dotnet00 wrote:
| Likely a mix of GPS, inertial guidance, vision and radio/laser
| beacons/ranging.
| generuso wrote:
| Falcon-9 relies on GPS and a couple of altimeters. (Filtered,
| as others have already said, with the help of data from the
| inertial sensors.)
|
| Compared to Falcon-9, Starship/Superheavy additionally has a
| command link from the ground. Whether it is used to coordinate
| the movement during the catch is not publicly known, but it is
| easy to imagine how this could be useful.
| shirro wrote:
| They have the experience and control systems to do this reliably
| with Falcon 9 so it seemed doable in time but seeing it on a new
| vehicle on the first attempt was still surprising. Really
| impressive engineering.
| h2odragon wrote:
| My wife asked "Why is this a big deal?", so I gave her a link to
| Handmer's 2021 explanation:
| https://caseyhandmer.wordpress.com/2021/10/28/starship-is-st...
|
| She's not an enthusiast; she's got an impression from SciFi that
| going to mars shouldn't be that hard.
| moffkalast wrote:
| Well I mean going to Mars isn't _that_ hard per se, a fair few
| countries have done it... but carrying enough supplies and
| shielding to last people 2 years until the return trip and then
| actually getting back are way harder problems.
|
| Seeing Starship get burnthrough on these suborbital launches
| really shows how hard it'll be to do Mars return entry with a
| fair few extra km/s.
| diebeforei485 wrote:
| Only the US and China have landed successfully on Mars. China
| achieved this in 2021. Russia/USSR tried multiple times and
| didn't succeed.
|
| Other countries have sent satellites to orbit around Mars,
| which is not the same thing.
| spacesanjeet wrote:
| I think that the number of countries reaching Mars (lander
| or orbiter) is in single digits and thus when talking about
| how hard it is to reach Mars and then come back, both of
| the scenarios kind of hold similar weights.
| mrandish wrote:
| Getting to Mars is hard but not _that_ hard compared to
| getting a large payload to Mars surface and back to Earth.
| Some people may assume Mars return is around twice as hard
| but it 's orders of magnitude harder. And that's before even
| contemplating doing so with a cargo of humans and the
| necessary tonnage for them to survive on Mars at least 26
| months.
| wolf550e wrote:
| Robert Zubrin's Mars Direct would have got "flags and
| footprints" on Mars without needing something like Starship. He
| worked on a version of SLS in 1989 in Martin Marietta that
| would have cost $1B and been ready in the second half of the
| 90s and would be retiring soon after many successful flight to
| Mars (and to the Moon), but instead we got SLS and Orion so we
| need Starship to get anything done.
| hnpolicestate wrote:
| Didn't Von Braun have a plan too? Nuclear rockets or
| something.
| wolf550e wrote:
| The difference is that Mars Direct was a conservative plan,
| wrt rocket technology. It just used existing Shuttle parts
| and was meant to fly from Shuttle pads in between Shuttle
| flights. It didn't require developing anything new, that's
| why they were sure it would be cheap and fast, and flight
| rate would make it possible for it to be reliable. SLS is
| that idea turned into a jobs program.
| boznz wrote:
| Regulations are hard enough just using methane, I wouldn't
| want to be the one filling out the paperwork if that was a
| nuclear rocket.
| davedx wrote:
| The Mars Direct book is worth reading not only for things
| like transport and mission design but also a wealth of other
| good ideas about how to "live off the land" when we get there
| too. Truly worth reading for anyone remotely interested in
| space exploration
| rkagerer wrote:
| That seems like way too long an article for a non-enthusiast.
| jcgrillo wrote:
| I was sure they were going to lose one of the fins at "max q part
| 2".. Looked like it burned through near the hinge.
| _ph_ wrote:
| If anything, the last 2 flights have shown how good a decisions
| it was to go with steel. The thermal reserves seem to be really
| large. While not as bad as with the previous flight, there was
| still significant leakage of hot air between the starhip and
| the flap. But it didn't seem to cause significant damage, at
| least as far as for the landing. For complete reuse, they
| probably have to still improve that a bit.
| honeybadger1 wrote:
| What an inspiring team SpaceX has.
| lquist wrote:
| What does Starship reusability mean for $/kg to LEO? I know there
| are longer term targets of $10/kg but that supposes efficiencies
| that aren't here yet. Would be helpful to understand before
| Starship reusability where the state of the art was in terms of
| $/kg to LEO and where we would be with impending Starship
| reusability.
| acover wrote:
| https://www.reddit.com/r/SpaceXLounge/comments/1bgmsm9/cost_...
| augusto-moura wrote:
| I don't think we have a number for it yet. But it will
| definitely be the cheapest launch system at the time of launch.
|
| People say 200$/kg just with booster reuse, and 20$/kg with
| full reuse. Of course this might be too optimistic, but I truly
| believe we might reach under 50$ in this decade.
| quotemstr wrote:
| Even $50 is within "going to the moon for my honeymoon"
| range. Wow.
| augusto-moura wrote:
| $50 is a number for LEO (Low-earth orbit). $/kg to a Moon
| orbit (or flyby) might be significantly more expensive. Not
| only that, because it is further so it needs more fuel, but
| also it is a few days trip which would need a bunch more
| kilos in provisioning food, water and other things. So
| yeah, unfortunately not that cheap to have a honeyMoon in
| the moon (heh)
|
| There is a lot of possibilities to make a trip to the moon
| cheaper though. If we make LEO that cheap, we can build a
| lot of infrastructure in the space that would make the
| tourism to moon more affordable. Like keeping a few
| starships always in orbit as some kind of space-hotel-metro
| system.
|
| This will probably take a few more decades, though.
| Valgrim wrote:
| Artemis by Andy Weir dwells a lot on this kind of
| infrastructure, but I never could understand the orbital
| mechanics described in the book.
| itishappy wrote:
| Only if you don't care about coming back!
| moffkalast wrote:
| This might be the best time to get into cubesat development
| as a hobby, lol.
| jackcviers3 wrote:
| What is a good estimate of the number of times these boosters
| and engines will be reusable?
| JumpCrisscross wrote:
| > _What does Starship reusability mean for $ /kg to LEO?_
|
| All we can say is under $1,000/kg. Which is conservative, that
| limit being about two thirds that of Falcon Heavy's theoretical
| cost to LEO in a reusable configuration.
| thinkcontext wrote:
| We can't give any estimate. The costs depend on how many
| times the stages are reused. They have targets but we don't
| know what will actually happen.
| thinkcontext wrote:
| The dominant variable is how often they can reuse the stages.
| Last I heard Musk was targeting dozens of reuses for the upper
| stage and hundreds for the booster. If they are short of the
| cost per kg goes up.
| asadotzler wrote:
| Everyone gets this wrong, cost is not price. SpaceX themselves
| launch Starlinks at about $1,200/kg but they charge customers
| closer to $12,000/kg. Do the math. Costs coming down are
| increases in SpaceX profits, not decreases in customer prices.
| max_ wrote:
| At this point I am finding it hard to hate Elon Musk.
|
| For everything he does that has annoyed me (like Gloating at
| people being bombed in the middle east) -- his business acumen
| has completely unlocked for people what they we thought was
| impossible.
| sbuttgereit wrote:
| People are complex. This is nuance.
|
| There should be nothing wrong with recognizing that any
| individual is a mix of things you're going to like and things
| you're not. That could be judged all the way to a mix of things
| which are morally correct, amoral, or immoral... but the
| reality is probably a mix.
|
| It should be OK to praise the guy for those good traits and in
| turn to criticize the guy for what he does wrong: both in turn
| calling out the specific actions and less "the person". Its
| rare that demonizing someone is really appropriate or anything
| other than self-serving and we should see those that make that
| effort in that light.
| nemo44x wrote:
| Yes he's amazing and we're lucky to live in a time and place
| where he can lead thousands of people that can do these things.
| He's an example of what's possible by a capitalist and how
| capitalism empowers individuals to shape the world and make it
| better for everyone. So naturally there's a group of people
| trying to stop him due to envy and other copes.
| BugsJustFindMe wrote:
| > _At this point I am finding it hard to hate Elon Musk._
|
| Eh. There's really plenty of room to celebrate SpaceX and also
| still hate him.
|
| It is often the case that the way the mega wealthy got there is
| through a pigheadedness that when it works out works
| spectacularly well. He's still demonstrably a shitty toxic
| human being who lives off the grift though (FSD when again?
| boring tunnels when again? hyperloop when again? how many
| billions of dollars in government subsidies? how many vehicles
| upsold on unfulfilled promises of next year next year next
| year?), and we can continue to wish for a world where someone
| with his resources and drive was also a grownup with
| functioning empathy instead of someone who consistently behaves
| like a petulant child.
| robertlagrant wrote:
| How many billions in subsidies has he had?
| postalrat wrote:
| He said about half of what Boeing had.
| panick21_ wrote:
| The only 'grift' that holds up is about FSD. Everything else
| is nonsense. They are making Boring tunnels, the costumer
| paid and they delivered. The company didn't take off as much
| as Musk hoped but calling it a 'grift' isn't accurate.
|
| Hyperloop was never promised, that's literally just people
| who don't like Musk made up. In fact he EXPLICITLY said 'I'm
| not gone build Hyperloop, its just an idea I had', and then
| people who don't like him 10 years later 'where is the
| promised Hyperloop'. How does that make sense? Musk never
| received a single $ for Hyperloop, but somehow this is a
| 'grift'.
|
| > how many billions of dollars in government subsidies?
|
| They are big cooperation's in capital intensive industries.
| When you build big investments, you get government tax
| reduction and other things, this is literally normal. If you
| don't like it, that's fine, but that how it works. Its not a
| 'grift' unless you want to go down the 'modern capitalism is
| grift' route.
|
| Outside of that, most subsidies he got, were just universal
| subsidies that anybody could get. The US government gave the
| same amount of subsidies to foreign companies selling EV cars
| in the US. This was a plan to increase EV adoption in
| general. And arguably it worked. How is again is this a
| 'grift'.
|
| And for SpaceX, I think its pretty clear that the government
| got much, much, much more then it ever paid for when they
| paid SpaceX. I would argue SpaceX has already saved the US
| government more money then they ever paid for SpaceX
| development. Just Clipper going on Falcon Heavy is billions
| in savings.
|
| There are plenty of reason to dislike him but those aren't
| really good ones. Except the FSD one, that one I think is
| quite bad. At least they finally allowed moving the FSD from
| one car to the next, but that's not enough.
| tensor wrote:
| You should be glorifying Shotwell, not Musk. Yes Must helped
| give her room to build but she's the genius and deserves the
| credit.
| panick21_ wrote:
| So funny that they had a little buoy water ready to film the
| explosion. I want to see the views of that camera from the
| landing itself.
| seydor wrote:
| Now we have no excuses
| metalman wrote:
| anybody not watching these live better be delivering a baby,or
| saving someones life its a very short list of things that should
| take precidence over what are the most astounding things
| happening for our species,ever
| nebben64 wrote:
| What is the object beside the rocket at 37:49 to 38:02 ? Is that
| debris ? It seems to be falling with, then away from the rocket.
| (it looks like a small glowing ring to the right)
| kevinmhickey wrote:
| It's the hot staging spacing ring. They didn't call it on the
| feed but it is an expendable part that ejects after separation.
| nebben64 wrote:
| thank you!
| Alex-Programs wrote:
| Hotstaging was added quite late so they need to jettison in
| order to land, but it should be permanently integrated in
| the later variants.
| nebben64 wrote:
| interesting, thank you for the extra info
| skizm wrote:
| This was insanely cool to watch. And on the first try!
|
| As a complete lay person with little to no physics knowledge:
| what stops the use of something dumb like a parachute, or even
| wings and landing gear, to "land" the booster? I assume it is
| impractical (since they don't do it), but what are the actual
| particulars that stop it from working? While super cool to watch,
| it seems crazy that plucking it out of the air like that is the
| best way to preserve the booster for reuse.
| ackbar03 wrote:
| physics?
| throw4950sh06 wrote:
| At the very least, reducing the number of concerns on the
| rocket is definitely worthwhile. They are going to have an
| engine in any case, and using just that and nothing else on the
| rocket itself simplifies testing and reduces risk. The tower
| can have a separate testing and there's no way something that
| happens on the way to orbit and back breaks the tower.
|
| Wings, parachute, etc... All very easy to break or burn at
| hypersonic speeds, and very chaotic to control. It probably (
| _very_ probably) wouldn 't be possible to land back exactly
| where the rocket launched on wings or chutes - that would
| probably need an extremely long and wide runway, but compare
| the size of Starship to the Space Shuttle... It's like braking
| a toy car vs braking an actual truck.
| ivandenysov wrote:
| It mostly comes down to reducing extra weight. You have to
| carry those wings and landing gear upwards, which reduces
| useful payload weight. But having the booster right where it
| started also helps with reusability. No need to transport the
| booster from a landing strip back to the starting table
| murderfs wrote:
| > As a complete lay person with little to no physics knowledge:
| what stops the use of something dumb like a parachute, or even
| wings and landing gear, to "land" the booster?
|
| The main advantage is that you don't need to spend any of your
| payload mass budget on a parachute, or wings and landing gear.
| The secondary advantage over a parachute is that you don't need
| to fish it out of seawater and make your refurbishment process
| more of a pain in the ass.
| avhon1 wrote:
| Parachutes give little or no control over where and how the
| rocket lands, are unreliable (unfurling fabric behaves
| chaotically; modern spacecraft still don't have 100%
| reliability on their parachutes), and are surprisingly heavy.
|
| Wings and landing gear are useless extra weight during launch,
| and excess weight on the booster has a super-linear reduction
| weight delivered to orbit. (the Tyranny of the Rocket Equation)
|
| During the 1960s, NASA investigated using inflatable Rogallo
| Wings (basically hang gliders) to land the Gemini capsule. It
| worked fine, but was more complicated than parachutes, and re-
| use was not one of the goals of the Gemini or Apollo programs.
|
| None of those give much margin for error on landing. Without
| any kind of propulsion, there's no option to come to a hover or
| do another go-around if the landing isn't going well. Space
| Shuttle pilots had to do extensive training in simulators for
| the landing because they only got one shot at it during the
| mission.
|
| Propulsive landing doesn't require any hardware that isn't
| already on the launch vehicle, only a little excess propellant.
| (And it is a small amount; Super Heavy is like a soda can
| that's full of liquid at launch and only has a swig at the
| bottom during landing.) Propulsive landing gives Falcon 9 and
| Super Heavy the ability to overcome wind and other weather
| conditions to make pinpoint landings. Engine throttling gives
| Super Heavy the ability to hover, so it has a huge margin for
| error when coming in for a landing.
|
| Super Heavy could have had legs, like Falcon 9, but it has such
| a huge payload capacity that they can simply choose to always
| launch with enough propellant to come back to the tower, and it
| saves a lot of flying weight and complexity by simply not
| having them. The arms on the tower can be massively overbuilt
| to ensure however much reliability SpaceX wants.
| georgeburdell wrote:
| SpaceX has unbaked bread
| zeristor wrote:
| I went to follow this on the SpaceX YouTube channel since it is
| usually closer to real time.
|
| It seems someone hijacked and played a video of the previous
| launch. Just as we got to launch time it cut to a fake badly
| dubbed speech by Elon Musk going on about Bitcoin, with a handy
| QR code.
|
| This was a bit confusing but since it was 10 minutes in advance I
| managed to switch to another channel.
|
| Still amazing, even if the video glitched at the key capture
| point.
|
| And an hour later the Starship itself re entered to soft salty
| sea landing.
|
| I don't know how many prototype runs they need to do, I'm
| guessing they could stuff a shed load of Starlinks into the next
| one.
| tofuahdude wrote:
| Sounds like you were on a scam, fake version of the channel.
| jader201 wrote:
| Can I hijack this thread for an almost completely unrelated
| question that I have observed in nearly every simulation of
| movement in space, even from sources like NASA and SpaceX which
| "should know better"?
|
| And I'm mostly asking this out of scientific curiosity, not as a
| criticism.
|
| Why do they always portray movement in space by showing stars
| moving past the view at variable rates, or even at all?
|
| The opening screen of this video while you're waiting for the
| feed to start shows stars moving that seem to be only feet away,
| and only a few inches in diameter. Like little orbs of light just
| passing outside the window.
|
| Isn't this highly unrealistic, for even extremely fast travel in
| space?
|
| I would imagine at most you would see very slow movement of a
| very static field of stars. But every depiction in sci-fi, video
| games, and other simulations like in this video insist on making
| it seem like space is full of tiny 6-12" stars floating only feet
| away from each other.
|
| Is there any explanation where this could actually be considered
| realistic that I'm not thinking of?
|
| I'm just a lowly software engineer, so my expertise in this area
| is null. But from a basic understanding of stars and physics,
| this seems unrealistic.
|
| Admittedly, I guess it wouldn't be very exciting to view movement
| in space in a way that I'm imagining would be realistic, and
| maybe that's the only explanation there is/needs to be.
|
| But I guess I'm thinking that there would be enough people at
| SpaceX (for example) to scream "this is not even close to
| realistic!" for something like that to not make it to production,
| even if it is more exciting to watch.
| KoolKat23 wrote:
| If they were truthful, you'd think the picture was frozen,
| signal issues etc.
| herval wrote:
| I'm guessing when making an artistic depiction of something
| going very fast in space, that sort of parallax helps? The goal
| of consumer content (including the ones by spacex) isn't to be
| realistic, it's to entertain
|
| That said, "the expanse" is an exception here - they make it
| look as realistic as possible, including the battles where
| ships don't even see each other. Stars barely move on it too
| andrewflnr wrote:
| You're correct, it's hilariously unrealistic (IIRC requires
| actual superluminal speed), but people have been conditioned to
| accept it by various scifi media.
| buildbuildbuild wrote:
| Imitating science fiction is great marketing for a space
| company.
|
| Brand association with familiar depictions of "the future" is
| the goal, not realism.
| ordu wrote:
| _> Is there any explanation where this could actually be
| considered realistic that I'm not thinking of?_
|
| You could record the full trip, and then speed the record up.
| What the point to watch at thousand years of the record with
| slowly changing picture, if you can watch it in a few minutes.
| lutorm wrote:
| As others have said, you're correct. But one reason for doing
| this, beyond just looking cool, is to give a visual cue for
| motion. The aim isn't primarily to _look_ realistic, but to
| make it as easy as possible to _interpret_ the outputs. Motion
| cues help with this.
|
| As an example, if you're watching an airshow against a clear
| blue sky, especially filmed with a long lens where you can't
| see the ground, it is very hard to understand what's actually
| happening because you can only see attitude changes, but not
| the velocity vector. Add just a few clouds in the background
| and the impression is very different.
| kylecordes wrote:
| In addition to the other ways this is incredible, it is a
| stunning achievement in software development.
| interludead wrote:
| The video looks like it's being played in reverse
| cs702 wrote:
| Awesome. Incredible. Inspiring. Words fail me.
|
| Heartfelt congratulations to the folks at SpaceX!
| goodgrief99 wrote:
| Why don't they mount moving video cameras? I mean, the second
| part of the fly is pretty boring. They shows us a view from 2
| static cameras. Is it so difficult to make one camera moving?
| With 360 degrees view. Show us the shape of the earth the full
| circle, show us the moon. Is it so hard?
| DiggyJohnson wrote:
| Yes what you're describing is nearly impossible.
| _flux wrote:
| I don't think they'd need to _actually_ have moving cameras
| (I think this is what the poster meant) to give a 360 degree
| view, but 360 degree cameras (well, 180 because they 're
| right next to an obstacle) that could be reprojected to 2d.
| lutorm wrote:
| The primary purpose of having those cameras is to gather test
| data, not provide entertainment.
| brcmthrowaway wrote:
| Does each engine have 6 degree of freedom to point its jet?
| lpribis wrote:
| No, each individual engine has 2 DoF (x-axis and y-axis
| rotation) which correspond to torque on x and y plane to the
| rocket. They need to use more than one at once (three in
| starship's case) pointing in different directions to get z axis
| torque.
| bjamesking wrote:
| I was watching a youtube stream with tens of thousands of viewers
| and 20 seconds before launch it switched to an AI generated video
| of Elon on stage talking about his "crypto currency program". It
| was so well executed and generated, it nearly felt real.
|
| The violent anger I felt and still feel for scammers has ruined
| my day.
| mlindner wrote:
| They do this every launch unfortunately. Youtube seems
| completely inept at stopping them. They make enough money to
| hire hundreds of thousands of fake accounts to subscribe.
| macintux wrote:
| Musk choosing to abandon YouTube to push his other company
| didn't help.
| sebzim4500 wrote:
| True, but even before that there were fake spacex streams
| (complete with a 'verified account' symbol) with 10k+
| alleged viewers.
| ivewonyoung wrote:
| These are reruns.
| VohuMana wrote:
| Wow, I knew they were going to try to catch the booster this time
| but I really didn't think it was going to work on the first try,
| I was just hoping they didn't destroy the launch tower in the
| process. Congrats to the SpaceX team, absolutely amazing! Hope
| y'all are celebrating
| beambot wrote:
| Highlights in a YouTube video:
|
| https://youtu.be/b28zbsnk-48?si=JamDRMuN07oWlcZi
| BurningFrog wrote:
| Do we know how much more efficient/cheaper landing by booster
| catch is compared to landing on a platform?
| malfist wrote:
| It's not just cheaper, it's preserving capacity. Every pound of
| landing gear you carry has to be offset with fuel to lift it,
| and then that fuel has to have fuel to lift it and on and on.
| rhegart wrote:
| Coolest video by far, but this still places 3rd for me behind
| F9's first landing, and the dual heavy landing. The future is
| bright!
| agumonkey wrote:
| SpaceX is really incredible in how regular the improvements are
| coming. Something in their structure is well balanced.
| bamboozled wrote:
| It has to be Elon, he is focusing a lot of energy on the
| company right now.
| shmerl wrote:
| Given his completely horrible jerk personality, I'd expect
| the opposite.
| briandw wrote:
| Imagine the number of amazing space telescopes that we are going
| to get! When it's cheep to launch a 10m diameter object into
| space, so many possibilites open up.
| _ph_ wrote:
| For things like that, they could build special versions of the
| star ship which remain in orbit as the housing. They would need
| no flaps, no tiles, just the 6 engines and the fuel tank. The
| body of the starship itself would be the telescopes tube.
| TyrianPurple wrote:
| "Any sufficiently advanced technology is indistinguishable from
| magic." and what we have witnessed is magic.
| jeswin wrote:
| Speaking as a non-American. SpaceX just made one of the most
| significant technological leaps in the last decade. This is
| obviously hugely significant in many ways, including retaining
| the US military edge.
|
| Yet the US administration hasn't congratulated SpaceX.
| Incredible.
| stetrain wrote:
| https://x.com/SenBillNelson/status/1845461454977196294
| abathur wrote:
| What counts?
|
| The current head NASA admin (a political appointee) did it a
| few hours ago and it's retweeted on the official @NASA account.
|
| (not linking as peer comment already did)
| dtquad wrote:
| There has been some kind of beef between Elon Musk and the
| Biden administration even before Musk's public right-wing turn.
| For example Biden has given speeches praising US EV vehicle
| manufacturers and not mentioning Tesla but mentioning all their
| competitors.
| stetrain wrote:
| Elon's "turn" included posting a bunch of COVID
| misinformation in early 2020, well before Biden was elected.
|
| The auto industry stuff is basically just union vs non-union
| politics. Other automakers that build cars in the US but at
| mostly non-unionized factories were also not part of those
| events.
| jfoster wrote:
| What did the post(s) say?
| stetrain wrote:
| https://x.com/elonmusk/status/1240754657263144960?lang=en
|
| https://www.theverge.com/2020/3/20/21187760/twitter-elon-
| mus...
|
| https://amp.cnn.com/cnn/2020/04/29/tech/elon-musk-
| twitter-co...
|
| Lots of examples. And I'm not just talking about his
| general opinions on government response, but actual
| misinterpretations and misstatements of data that were
| straight-up wrong.
|
| It was also a clear breaking point between Elon and local
| and state government in California over how local
| restrictions were going to affect Tesla's factory in
| Fremont.
| jeffnappi wrote:
| It's unfortunate that Elon has made himself so visibly
| political, it casts a dark shadow on the great work of the
| people at his companies.
| robwwilliams wrote:
| Awesome achievement. Watched it with my sister at home and
| brought back memories from the 60s in front of the B&W TV
| watching some of the early amazing flights and landings.
|
| Question for hackers: How does this reorient space programs
| world-wide? If I were a politician or technocrat in China,
| Russia, or the EU this would feel like an inverse and intense
| Sputnik moment -- "holy sh--- we have to up our game!"
| creer wrote:
| Eventually it convinces everybody that "quantity in space" is
| possible. Moving to projects where you don't have to count
| every ounce. It opens the path to wild schemes, in amount of
| weight that could be moved.
|
| And why "eventually"? SpaceX should have already convinced
| people of that. Yeah it's not yet in production, but the
| momentum and progress have been amazing to witness.
|
| (The previous one was convincing everyone that there was lots
| of space for tech improvement. Wake up call achieved just a few
| years ago also by SpaceX.)
| asadotzler wrote:
| It doesn't. It makes one or two mega-constellations cheaper for
| their operators and therefor more profitable, but no one except
| telecom and sensor platforms really want orbit. It's useless
| for most things, far worse than working on the planet's surface
| where all the labor and materials already are.
| erichocean wrote:
| Imagine not being Team Elon.
| perlgeek wrote:
| During/before the water landing of Ship, the telemetry indication
| for the rocket motors stayed off.
|
| Does that mean the landing burn was unsuccessful? Or was that
| just a glitch in the telemetry?
| stetrain wrote:
| In the video you can see the engines light (reflecting off the
| metal control flap and water) and the ship make a soft
| touchdown on the water. It then tips over and the tanks pop
| from the force of smacking the water sideways.
|
| So the landing burn seems to have been a success.
| sebzim4500 wrote:
| It's weird, that happened last time too so you'd think if it
| was a glitch they would have fixed it.
| FergusArgyll wrote:
| The joy on the faces of all the employees is infectious,
| congrats!
| gyre007 wrote:
| Incredible achievement, my American friends! Congrats! We,
| Europeans, can only feel jealous, but hey at least we have free
| [but comically broken and dysfunctional] healthcare, so, there's
| that. I hope you'll bring a lot more progress to humankind beyond
| space exploration!
| mrandish wrote:
| The long-term goal is becoming a multi-planet species, so in
| that context it's not about countries. Go Earth!
|
| (also, while NASA has been generally helpful to SpaceX's
| efforts, American FAA bureaucrats have managed to inject
| unnecessary delays and uncertainty into the process (in
| addition to some necessary delays).
| yborg wrote:
| Amazing achievement, but also reminds me that what NASA and its
| contractors accomplished during the 1960s still stands with
| current day systems engineering.
|
| The 3rd Saturn V launch put three men into orbit around the Moon.
| The 6th landed two of them there.
| h_tbob wrote:
| We live in a day and age where it seems that all the innovations
| we see now are new tech that has to do with electronics.
|
| Good to see some good ol hardware breakthroughs in another
| industry.
| dang wrote:
| [stub for offtopicness]
| rvnx wrote:
| Edited: Was asking what were all these deleted comments.
|
| Got my answer: it's a theory that SpaceX is a partner for the
| US DoD and is not just an internet provider.
| Culonavirus wrote:
| [flagged]
| JumpCrisscross wrote:
| > _What the f is going on in this_
|
| Genuinely curious if you find an answer.
|
| My first thought was nuclear anxiety; it's nice to feel
| like we have a secret shield in space. Then I saw Trump
| talked about it, so my current hypothesis is the partisan
| parroting that happens on both sides. (Or if someone
| _doesn't_ like military spending, maybe it's an anti-Musk
| thing?)
|
| That said, the three accounts that have been posting about
| it seem to _really_ like this topic [1][2][3], so maybe
| it's a niche thing. They all seem to really like one Reddit
| thread.
|
| [1] https://news.ycombinator.com/threads?id=forgot-im-old
|
| [2] https://news.ycombinator.com/threads?id=tbone902
|
| [3] https://news.ycombinator.com/threads?id=georgeg23
| perihelions wrote:
| I recommend emailing hn@ with your questions, even if you
| don't currently see any obvious reason to.
| JumpCrisscross wrote:
| Guessing the massive flag storm will ruin someone's
| Monday.
| 486sx33 wrote:
| I'm just talking totally out of my A S S. Wouldn't it be
| cool if this starship launch somehow utilized starshield
| for grabbing starship, like proof of concept to the
| military of some kind of hyper accurate military grade GPS
| that can pinpoint a rocket and control it to the accuracy
| of between two chop sticks?
| fasteddie31003 wrote:
| I hate to bring politics into such a momentous occasion, but as
| a lifelong Democrat, I think Trump might get my vote because of
| his alliance with Elon. Elon clearly is a once-in-a-century
| human who has progressed humanity more than anyone else in
| history. I think we need to let him achieve his goals without
| being burdened by government bureaucracy. Unfortunately, the
| Democrats have aligned against Elon. It didn't have to get this
| way, but it has. A Trump presidency will allow Elon to progress
| more, bringing humanity with him. I hate Trump and I think he
| is a narcissistic idiot, but he supports Elon more than Kamala.
| ilrwbwrkhv wrote:
| The great dichotomy of man. Elon is a hardheaded questionable
| fellow who stops free speech on his platform if it doesn't
| suit the agenda and is supporting Trump who literally spurred
| an insurrection.
|
| But Elon also started one of the greatest revolutions mankind
| has ever seen, up there with the Apollo project, which one
| can say is mankind's greatest achievement.
|
| What do you do with that dichotomy is up to you to resolve.
| grecy wrote:
| Elon will be able to achieve his goals just fine under the
| Democrats.
|
| Trump will run so much stuff into the ground nobody will be
| able to achieve anything.
| busymom0 wrote:
| Does anyone know what this circular thing is at 5:36 mark in the
| below video under the booster? It's like a piece which separated
| and keeps falling off.
|
| https://i.imgur.com/z6PH2Jw.png
|
| https://youtu.be/b28zbsnk-48?t=336
| hnpolicestate wrote:
| This is why Musk is silly when he claims fear over what certain
| possible gov administrations would do to him if elected.
|
| He's allowed to believe whatever he wants. He's too valuable to
| the United States. Imagine what a BRICS country would pay for his
| talent? Worth his weight in gold wrapped platinum.
| georgeburdell wrote:
| It's justified.
| https://www.latimes.com/california/story/2024-10-11/la-me-sp...
| ChuckMcM wrote:
| Pretty impressive. The engineering team at SpaceX is really
| something. Some thoughts;
|
| The 'chopsticks catch' was amazing to watch. Seems like it adds a
| lot of risk and clearly the booster needs additional fire
| suppression systems :-) perhaps the tower could mount something
| that sprays the booster like the barges have for the F9 boosters.
|
| The heatshield held out for a much longer time, the asymmetric
| heating on the flaps was interesting. I had guessed that all four
| flaps would have equivalent heating based on an approach that was
| basically that side of the rocket perpendicular to the flow but
| it seems like that isn't the case. Still it seems like they are
| close to having something workable here.
|
| The detonation at the end was pretty spectacular too, but I
| suspect that structurally the tanks failed as the rocket hit the
| water vs anything that was an engineering failure. Engineering it
| to be strong enough to land on water would presumably compromise
| the cargo to orbit number.
|
| The use of Starlink was really interesting. The ability to get
| live video for the entire re-entry is pretty game changing for
| engineering. I'd guess there are even more 'views' than they
| showed (there would be if I were running things :-)) but overall
| that capability is something that really helps evaluate the
| changes made.
|
| I can easily imagine that flight 6 will be nominal end to end
| without any unintended damage. That would enable, perhaps, one of
| their 'massive' Starlink missions to test cargo delivery. It will
| also start to give us some better numbers on exactly how much
| cargo Starship can put in orbit in 'full reuse' mode which is
| essential if they want to create a fueling station on orbit for
| the Artemis program.
|
| Again, hats off to engineering at SpaceX, y'all did good.
| nordsieck wrote:
| > The detonation at the end was pretty spectacular too, but I
| suspect that structurally the tanks failed as the rocket hit
| the water vs anything that was an engineering failure.
|
| It's possible that SpaceX programed the AFTS to trigger some
| time after the rocket touched down in the water. Just to make
| sure that it completely submerges quickly.
|
| > I can easily imagine that flight 6 will be nominal end to end
| without any unintended damage.
|
| I think it depends on what you mean by "nominal". SpaceX
| ultimately wants to catch the 2nd stage as well. I suspect that
| they are a ways off of that, since it would have to approach
| over land. The FAA is going to need to have very high
| confidence that it will do exactly what it's designed to do
| before they're going to allow that.
| 317070 wrote:
| > Just to make sure that it completely submerges quickly.
|
| Why would they want to do that? (genuinly curious).
|
| I reckon there would be a lot of useful data left if they
| could recover or even just inspect the remains. The remains
| are one big tank, so it would have floated.
| eco wrote:
| No doubt it would be very useful to recover. SpaceX isn't
| the only one who could pluck it out of the Indian ocean
| though. You don't want to leave a prototype for the most
| advanced Spacecraft ever made just sitting around for
| competitors to grab (most notably China which is currently
| speed running SpaceX-like designs).
| creer wrote:
| It landed right next to their own camera-bearing buoy.
| You can bet their own recovery ship was right nearby. And
| with access to radio control too. Likely with a couple US
| military ships on hand too.
| wiz21c wrote:
| I certainly hope so. Ocean are polluted enough and
| although such a ship is just a, well, drop in the ocean,
| the ideq of accepting to pollute more is unbearable to
| me, especially for a world class company like SpaceX...
| m4rtink wrote:
| It might not be that simple - I've read an article how
| they recovered one of the solid rocket boosters from the
| first successful Ariane 5 flight to check all was fine.
| IIRC it was a slog, they had to tow it back very very
| slowly, avoid it sinking, fighting all kinds of weather
| and tow line issues, etc. Have not found the article, but
| there is a picture how it looked like[0].
|
| With Starship it could have been similar & possibly worse
| given the size and more complex shape (various voids that
| might fill/drain & the thing is not really built for
| floating). Also you are in the middle of an ocean (Indian
| in this case) with potential for all kinds of weather on
| the way. Towing might again be very slow, so you might
| need to stage a massive submersible transport ship or
| something similar to make a recovery successful. And then
| the thing might still tip over and explode anyway -
| meaning all this was in vain.
|
| I think is most likely they won't bother and instead just
| stream as much data as possible over Starlink in real
| time (or heck, even via WiFi once the buoy is in range)
| for analysis. They want to catch the shop eventually
| anyway, so manual post flight analysis will wait.
|
| They can now check all over the first recovered booster
| anyway. :)
|
| [0] https://www.flickr.com/photos/europeanspaceagency/370
| 0131835
| 317070 wrote:
| But, couldn't they wait for like, 6 hours? Take a good
| look when it's cooled down a bit. Send some drones over
| to film it, and then sink it?
|
| I get that towing is probably too expensive for what it's
| worth. But I'm surprised they don't even go pick up some
| tiles before kablooing it.
| creer wrote:
| Attach a tether to one of the fin pods, then blow up the
| rest to sink it cleanly and bring back the important
| part.
| creer wrote:
| Possible yes but still, this is a prototype with new fin
| configuration, materials and lots of detail to be
| understood from inspecting it in detail. An inspection
| would be very useful.
|
| At the same time, this is SpaceX and they have a few
| others ready to launch already. Perhaps they indeed can
| keep it somewhat coarse and wait for detailed inspection
| until one of them makes it right back to solid ground?
| eco wrote:
| The previous ship did not come down where it was supposed
| to. I don't think they wanted humans anywhere near where
| it was coming down, at least until they can reliably do
| pinpoint landings. Even the Falcon 9, as accurate as it
| is, doesn't have humans anywhere near the landing
| location.
| esskay wrote:
| Yep this will be the reason. And lets not forget that
| Bezos was able to find and recover the Apollo 11 Saturn V
| engines from point nemo. If that was relatively simple
| you can bet plucking a freshly dropped entire starship
| from the indian ocean would be a doddle, especially when
| sat views likely show exactly where it landed.
| iknowstuff wrote:
| correct me if I'm wrong but I don't think the second stage is
| meant to be caught. It will have legs to land on Earth/Mars
| without any landing infrastructure.
| sebzim4500 wrote:
| It will have legs for Mars but they plan on catching it on
| Earth.
| ls612 wrote:
| It is expected to land astronauts on the Moon as well this
| decade, which will certainly require legs.
| DarmokJalad1701 wrote:
| That is a different version. The ones launching/landing
| on Earth are supposed to be caught by arms similar to the
| booster.
| Isamu wrote:
| I imagine that they will be their own first customer - putting
| Starlink satellites into orbit while they are gaining
| confidence in the reliability of the system for external
| customers.
|
| They have to prove out the landing of the second stage, either
| with another catch or with landing gear, which they need for
| the lunar lander anyway.
| creer wrote:
| They showed 4 streams at once during some of the reentry. One
| view of each control surface. They may have had still more
| views but just that 4 was a first.
| asdf123qweasd wrote:
| Imagine, linking that video into a 360deg virtual cockpit As
| if you were inside a booster made from glass.
| startupsfail wrote:
| There's a need for competition. I'm expecting that with Musk
| fully on the Trump train, there'll be no bright future at Space
| X.
| mciancia wrote:
| Why?
| olddog2 wrote:
| If elon can do everything he's done with an increasingly
| hostile govt, imagine what he'll be able to so with a
| supportive one
| profmarshmellow wrote:
| elon is a poster boy created by the government
| zenerdiodes wrote:
| Yes, this needs wider coverage
|
| https://www.reddit.com/r/WikiLeaks/comments/1fy10k1/track
| ing...
| HarHarVeryFunny wrote:
| Trump is pro big oil, not electric, so Tesla wouldn't be
| getting any more favors/subsidies under Trump, and with all
| the NASA money currently flowing to SpaceX, no strings
| attached, I doubt they would benefit from Trump either.
| Money coming from Trump will always be conditional on him
| getting something back.
| mlindner wrote:
| Burt Rutan, one of the most legendary aerospace engineers of
| all time used to do regular long presentations to people on
| why global warming was not man made. Some of them are
| archived on youtube. And there's many other cases of
| otherwise smart people having bonkers opinions in areas
| outside of what they are experts in. If anything, successful
| people are significantly more likely to do this. It rarely
| results in their downfall.
|
| SpaceX will do just fine.
| ceejayoz wrote:
| See also: https://en.wikipedia.org/wiki/Nobel_disease
|
| "You are a genius!" messes with the brain if heard enough.
| bluescrn wrote:
| If SpaceX is overly hindered by regulation/lawfare, then
| there'll be competition from China before long.
| hooloovoo_zoo wrote:
| I don't think so; there remain few economic reasons to go
| to space and spacex's customer isn't going to rely on a
| Chinese company.
| robotnikman wrote:
| The engineers at spaceX are amazing, and I'll admit I envy
| their tenacity and genius.
|
| The amount of progress we have seen in rocketry and space
| travel in the last decade is mind blowing, I never thought I
| would see this in my lifetime.
|
| Edit: Decided to give it a shot and applied for a backend
| software engineering position at SpaceX. I'm not sure if it
| will be noticed, but its worth a shot. I may not be a rocket
| scientist, but it would be great to contribute using the
| knowledge I do have.
| supportengineer wrote:
| We could have had this all along.
| ceejayoz wrote:
| Eh, maybe. There's a lot of computing and telemetry going
| on that benefits from the last twenty years of
| miniaturization and performance. The iPhone seemed
| impossible when announced to BlackBerry; tech has gone
| crazy fast.
| collinmanderson wrote:
| It's a lot easier to model and simulate too.
| Teever wrote:
| You should take a look at what Von Braun was planning for
| the Saturn V by the mid 1970s.
|
| IIRC they were talking about 100+ Apollo launches to get
| a real space station, moon base, and expedition missions
| to Mars by 1980 and with that would have come a real
| drive to innovate and improve on the Saturn V.
|
| Without the computational power that we take for granted
| today they would have definitely brute forced their way
| to elegant solutions and got somewhere close to where we
| are by the mid 90s.
|
| This would have lead to tremendous innovations in solar
| panels, batteries, and metallurgy much sooner than we
| ended up getting to them.
|
| Instead we chose a different path and made ourselves
| completely dependent on oil.
| ceejayoz wrote:
| A lot of those plans were just plain goofy. The Shuttle
| was supposed to generate the same sort of awesomeness,
| too.
| Teever wrote:
| Apollo was pretty goofy if you think about -- Yeeting a
| couple of dudes to the moon in a giant ass rocket so that
| they can tool around in a little electric-go cart with
| lawn chair seats and play some golf but it worked.
|
| I think that the Saturn V was a solid platform that was
| robust enough to do the kinds of things that Von Braun
| and others had in mind as well as versatile enough to be
| improved upon.
|
| They would have done it with sufficient budget but the
| political drive wasn't there. The politicians were more
| concerned with killing Vietnamese and Cambodians and then
| selling out American interests to oil companies.
| fsloth wrote:
| I guess the main problem was nobody had a budget for
| those plans. "Technically speaking we can do it but we
| can't afford it" unfortunately still means "we can't do
| it".
|
| Now only if Project Orion had not been canceled due to
| international treaties banning nuclear testing we'd be on
| the moons of Jupiter by now (sigh).
| neverrroot wrote:
| We just needed more people like Elon.
| reagansdi wrote:
| Elon acts more like a conduit between DARPA+Heritage
| Foundation and good engineers, the objectives are not
| always as idealistic as Mars https://www.reddit.com/r/Wik
| iLeaks/comments/1fy10k1/tracking...
| neverrroot wrote:
| Boeing does much much more of that.
|
| Why don't they deliver, in spite of them being decades
| more experienced in this area? Why don't they deliver in
| spite of getting much more money from the government and
| from your mentioned complex?
| zenerdiodes wrote:
| Engineers are more enthusiastic about Mars and willing to
| work 60hrs/week. Of course as that link shows that's a
| deceptive front, but it has been working. Ultimately he's
| a massive defense contractor.
| neverrroot wrote:
| Outstanding engineers care of doing engineering and
| making progress. And having a leader they can see burning
| for a mission and a goal. A leader who gets down and
| dirty with them.
| throw9474 wrote:
| It's hard to trust Musk at all once you read his back
| story https://www.reddit.com/r/WikiLeaks/comments/1fy10k1
| /tracking...
| kevinsync wrote:
| Sure. As a human he's (at best) a deeply-flawed agent of
| chaos (aren't we all to some degree?)... but at the same
| time we DO need a lot more people like him to put
| blinders on and act as undeniable agents of change.
|
| For better or worse, he's single-handedly facilitated
| watershed progress in more areas than just about any
| individual we can name from recent times. All the
| "cringe" and human shit he does that we hate and clown on
| will be erased by history and forgotten when the stuff
| that -other people- create, as a byproduct of him
| starting and funding these companies, pushes us forward
| and eclipses the clickbait and/or questionable personal
| behavior of the man himself.
|
| Teamwork makes the dream work, and I believe sometimes we
| need gigantic egos to set the ball firmly in motion.
| ridgeguy wrote:
| No. It all depends on cheap computation, reliable/free
| satellite location systems, and other stuff that weren't
| things in the (60s, 70s, 80s - pick your own starting point
| for "all along").
| bagels wrote:
| It's as much the economics as it is the technology. It
| took a ton of private investment, and government
| investment to get here.
| looofooo0 wrote:
| A rocket a day keeps the cost away.
| FrustratedMonky wrote:
| It is hard to reconcile the Musk that has built
| SpaceX/Starlink, todays launch was amazing, and the Musk that
| bought Twitter and turned it into a propaganda arm of the Trump
| Party.
|
| What is the real Musk?
|
| Is Mars the real goal, and even if he has to buy off Trump, it
| is justified if it gets us towards that goal.???
|
| Edit: Wow. I guess lesson learned. Don't question Musk's
| motives on HN. Even if the question was about Mars. Questioning
| is frowned upon. Is it still safe to question anything about
| Sam Altman? Or is that taboo now too?
| strathmeyer wrote:
| Musk bought SpaceX and Starlink just like Twitter.
| MarkusQ wrote:
| This technical term for this is "false".
| ralusek wrote:
| Are you perhaps thinking of Tesla? SpaceX was founded by
| Musk.
| roca wrote:
| Both. A single person can be great in some areas and a
| malicious loon in others. In fact, great success in one field
| can provide the self-confidence and capital to be a
| catastrophe in others.
|
| But also keep in mind that Musk isn't personally designing
| and building everything SpaceX does. The staff at SpaceX
| deserve more credit than they get, especially Gwynne
| Shotwell.
| le-mark wrote:
| That is true, but it's also true of Blue Origin who are far
| behind spacex in so far as flying real hardware. The
| difference is Musk maniacal zeal and yes leadership. I'm
| frustrated with Musks politics too, but his drive can't be
| denied.
| vl wrote:
| But why are you frustrated with Musk's politics? The fact
| that one of the smartest people chooses to demonstrate
| their view is very remarkable. It does warrant critical
| thinking and examination. After all he could have kept
| quiet and ponder to both parties equally.
| neverrroot wrote:
| Elon is into politics because it's politics who stood in
| his way of progress first.
|
| He's imho afraid and rightfully so, Twitter was a clear
| example of why.
| Anon1096 wrote:
| It's become an absolute meme on the left-leaning internet
| to say SpaceX isn't Elon and Shotwell is doing all the
| work. You can't go to a thread on this site or reddit etc
| without it being brought up.
|
| Really I am pretty sure it is just coping to deal with the
| uncomfortable fact that Elon (bad guy) is doing something
| great and clearly is skilled. Ask anyone at SpaceX or
| Shotwell herself and they will all say Elon is very
| important to its success.
| roca wrote:
| Maybe that's a meme, but obviously I'm not saying that.
|
| The problem is that people watch these videos and it's
| all ELON ELON ELON. Most of them don't even know
| Shotwell's name.
| retinaros wrote:
| you are almost there. if you remove your bias that is the
| environment and monoculture where you grew, you will see that
| Musk just seeks one thing. freedom for men to go beyond their
| shelves. speech is the easiest way anyone can use to do that.
| hence why it should be free. space is a bigger frontier.
| wannacboatmovie wrote:
| It's hard to understand why people care so much about
| someone's personal political opinions.
|
| This is especially prevalent when working in places like
| Seattle and SF. People ostracizing their coworkers because of
| wrongthink.
|
| MDS like TDS is real. It's extremely toxic and it needs to
| stop. People's political beliefs are their own and connecting
| that to work is a recipe for disaster.
| Tronno wrote:
| > It's hard to understand why people care so much about
| someone's personal political opinions.
|
| People care because he has power and money, which he uses
| to shape the world in alignment with those political
| opinions.
|
| The same is true of anyone else with power - Xi, Putin,
| Gates, Thiel, Zuck, and the countless others with influence
| over business and government. A lot of money is spent to
| analyze and alter their political opinions.
|
| What's hard for me to understand is why this isn't plainly
| obvious to you.
| FrustratedMonky wrote:
| He isn't a co-worker. He's a billionaire that can fund
| entire campaigns. It is a lot more like if my co-worker was
| really my boss, and he really cares about my political
| leanings during a performance review.. Thus I also care
| about his.
|
| "Metastable deexcitation spectroscopy (MDS) and thermal
| desorption spectroscopy (TDS)"
|
| I really don't know what you are talking about.
| slater wrote:
| "Musk Derangement Syndrome" and "Trump Derangement
| Syndrome" - labels that the pseudo-fascists like to apply
| to people calling out the words and actions of those two
| guys.
| zenerdiodes wrote:
| Correct
|
| There's clear evidence implicating Musk at this point htt
| ps://www.reddit.com/r/WikiLeaks/comments/1fy10k1/tracking
| ...
| meowkit wrote:
| Musk and Trump
|
| Derangement Syndrome
|
| Is what the acronyms refer to. Its a meme for the
| obsession around them specifically.
|
| My two cents is that there are other billionaires doing
| significantly more harm than those two. They just keep
| quiet or own news media platforms.
| Teever wrote:
| Is it so hard?
|
| See if you can try and steelman the argument as to why
| people care about the political opinions _and_ actions of
| the world 's richest man.
| unethical_ban wrote:
| The man in question personally has more wealth than many
| nations, co-opted one of the most popular American social
| media networks in the country and is a massive hypocrite
| when it comes to free speech.
|
| Musk isn't just some guy near your cubicle complaining
| about Mexican cooks.
| bluescrn wrote:
| SpaceX is not Musk. It may be executing his vision, but it's
| a team of thousands of skilled and hard-working people, all
| eager to work on a Sunday for a chance to pull something like
| this off.
| neverrroot wrote:
| But he's the catalyst for it all. There are other
| billionaires in this game too, why can't they replicate his
| success? Why can't they hire his engineers? Why can't they
| deliver the results?
| FrustratedMonky wrote:
| And Apple isn't Steve Jobs? Apple would have turned around
| on its own without Jobs?
|
| I think we all know these big companies have thousands of
| people working for them, and a lot of them are pretty
| smart.
|
| That doesn't change the influence the top guy has.
| ponector wrote:
| Twitter is not Musk. It may be executing his vision, but
| it's a team of thousands of skilled and hard-working
| people, all eager to work on a Sunday for a chance to
| create a propaganda arm of Trump party.
| profmarshmellow wrote:
| Musk is just a front man. He's just an actor like Trump. God
| knows who is behind them. Banks, "The Matrix" , can anyone
| fill it in ? The front men are certainly just reading
| scripts, it is obvious.
| reagansdi wrote:
| Project 2025 helped clarify it for Musk https://www.reddit.
| com/r/WikiLeaks/comments/1fy10k1/tracking...
| ninetyninenine wrote:
| >The heatshield held out for a much longer time, the asymmetric
| heating on the flaps was interesting. I had guessed that all
| four flaps would have equivalent heating based on an approach
| that was basically that side of the rocket perpendicular to the
| flow but it seems like that isn't the case. Still it seems like
| they are close to having something workable here.
|
| Heat shielding didn't look relevant at this section of the
| flight at all. The booster didn't have any shielding.
| cpeterso wrote:
| What's the advantage of catching the booster over landing it in
| the ground? Catching it seems like an extra complication.
| bagels wrote:
| You save the mass of the landing systems, you get to have all
| that mass on the ground and not have to lift it into space.
| Dramatically improves the performance of the rocket.
| __d wrote:
| I can speculate ...
|
| I think the primary reason would be that landing legs are
| heavy, and it wastes performance to carry them. If your
| landing mechanism is mostly on the ground, you get that
| performance back.
|
| Secondary reasons might include that it's simpler to get the
| booster right back to the pad. Once things have settled into
| an operational cadence, it's likely feasible to lower and
| lock the booster onto the stool, stack a ship on top, refuel,
| and relaunch -- no more messing around with barges,
| transport, weather issues, etc.
| wcoenen wrote:
| The rocket equation implies that if you want to maximize the
| delta-v a rocket gets out of a certain amount of fuel, then
| you should get the dry mass as close to zero as possible.
| Eliminating landing legs helps a lot.
| ro_bit wrote:
| The catch looks amazing, but one thing I don't understand is why
| SpaceX needs the technology to catch a booster they've already
| demonstrated the ability to land boosters on barges. Is the arm
| more cost effective to scale compared to a barge?
| mlyle wrote:
| The argument is that you don't need to spend the vehicle mass
| on legs, so you get performance.
|
| On the other hand, I imagine you could wipe out any benefits to
| $/mass launched pretty quickly by blowing up the tower.
| msk-lywenn wrote:
| Maybe the goal is to refill and relaunch immediately?
| slashdave wrote:
| This. You can lower the rocket back on the launch base,
| refill, and launch again within hours.
| valine wrote:
| The landing legs are heavy. SpaceX would rather have more
| payload than carry legs to space on every launch.
|
| Also landing on the launch pad means you don't have to
| transport the rocket. Just have the arms set it down and you're
| ready to launch again.
| _djo_ wrote:
| This booster is much, much larger than the Falcon 9 first
| stages that land on barges. It's ~70 metres high, versus ~40
| metres for the Falcon 9 first stage, and weighs about 275 000
| kg compared to the ~20 000 kg of the Falcon 9 first stage.
|
| In short, it would require such huge and heavy landing legs and
| landing barges that it probably wouldn't be feasible.
| mock-possum wrote:
| Holy shit I didn't realize it's an order of magnitude heavier
| cryptonector wrote:
| Weight. Legs weigh a lot. That's dead weight for a launch
| system, and it serves only to reduce payload to orbit.
|
| For Falcon 9 that's not that big a deal because they're NOT
| trying to reuse the second stage. Whereas with Starship they
| need more fuel to recover the ship, and that means they need to
| save weight elsewhere to avoid losing too much payload to
| orbit.
| iamcreasy wrote:
| SpaceX is also not very happy with the pair of forward flaps
| and 10 ton thermal protection needed as control surface and
| re-entry.
| gramie wrote:
| When I was visiting the space center in Huntsville, Indiana, I
| had a chance to talk with one of the volunteers. His name was
| Brooks Moore (https://www.youtube.com/watch?v=O3hudRA3yL8), and
| he had been the director of navigation systems for the Apollo
| (and other) projects.
|
| The first SpaceX barge landing had just taken place, and I asked
| him what he thought. He got a faraway look in his eyes, and
| agreed that it had been spectacular. For those guys, it must have
| seemed like all of their dreams were coming true.
| robbiet480 wrote:
| I believe you meant Huntsville, Alabama?
| atlgator wrote:
| Nothing short of inspiring. Moving humanity forward. Well done to
| the SpaceX team.
| ramshanker wrote:
| Ok. I will admit this. SpaceX Engineering is making me feel
| regret for not choosing Aerospace Engineering back in Undergrad.
| Oh well, That Tower is almost within Civil-Structural
| Engineering.
| cubefox wrote:
| Here is Scott Manley's summary and analysis of flight 5:
|
| https://youtube.com/watch?v=Ysx4t7ICO58
| Yacovlewis wrote:
| People on earth are experiencing the Jetsons and the Flinstones
| at the same time
| 1shooner wrote:
| This is what makes it bittersweet. So many comments here
| talking about this being progress for 'humanity'. I may be
| cynical, but most of humanity will get no benefit from any of
| these accomplishments. This is technology owned by and
| ultimately in service of a minuscule fraction of humanity.
| Yacovlewis wrote:
| Based on this conversation, how many of y'all are actual rocket
| scientists? I'm blown away by the expertise in some of these
| comments
| geepytee wrote:
| I just quit my job at a SaaS. What am I doing with my life... The
| SpaceX team just caught the biggest rocket in history with a
| giant arm, we all need to dream bigger!
| efxhoy wrote:
| Strategically this is huge for the US and NATO. Being able to put
| orders of magnitude more payload in orbit at a fraction of the
| cost of the competition is a huge advantage in controlling space.
| Starlink and starshield are already years ahead of what china and
| russia has, starship is going to widen that gap even further.
| qaq wrote:
| Well if US would deploy global kinetic bombardment system that
| would def. be a game changer.
| WalterBright wrote:
| As an ME/AE, I can say this is an astounding engineering
| achievement. And on the _first_ try! Well done, SpaceX!
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