[HN Gopher] NASA's Europa Clipper Launch
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       NASA's Europa Clipper Launch
        
       Author : belter
       Score  : 173 points
       Date   : 2024-10-14 15:28 UTC (7 hours ago)
        
 (HTM) web link (www.youtube.com)
 (TXT) w3m dump (www.youtube.com)
        
       | consumer451 wrote:
       | Alternate streams with commentary...
       | 
       | Everyday Astronaut: https://www.youtube.com/watch?v=IAixoyE78rE
       | 
       | NASA Spaceflight: https://www.youtube.com/watch?v=9JUn8LmGYEA
       | (This is not an official NASA stream)
        
         | diggan wrote:
         | And for people who prefer text:
         | https://www.washingtonpost.com/science/2024/10/14/europa-cli...
        
           | ralfd wrote:
           | > The journey to the Jupiter system is expected to take five
           | and a half years, arriving April 11, 2030, for four years of
           | observations.
           | 
           | See you in five years!
        
             | imzadi wrote:
             | Cool, I finally have something to live for
        
               | dotancohen wrote:
               | Hopefully we'll see humans back on the Moon, and cheap
               | reusable human-rated spacecraft on Mars, before then.
        
         | p1mrx wrote:
         | Spaceflight Now: https://www.youtube.com/watch?v=tZjszhRVo9s
        
         | whitehexagon wrote:
         | The NASA+ stream died for me "404 The cosmic object you were
         | looking for has disappeared beyond the event horizon." I much
         | preferred the old IBM stream they used to use. Shame, but at
         | least it sounds like the launch was a success.
        
       | sidcool wrote:
       | Are the side boosters going to be recovered?
        
         | ceejayoz wrote:
         | No. All cores expended in this launch.
        
         | benjismith wrote:
         | Nope. They needed the maximum amount of thrust from those
         | boosters in order to propel the spacecraft toward Jupiter, so
         | they couldn't save enough fuel for the boosters to land
         | themselves. This was the 6th flight of these boosters, so we
         | thank them for their service!
        
           | linotype wrote:
           | Is this one of those things that's limited by physics or at
           | some point will these kinds of missions be doable with a
           | mostly reusable setup?
        
             | malfist wrote:
             | It's the tyranny of the rocket equation. The more you send
             | up, the more fuel you need to send up and then you need to
             | send fuel to lift that fuel and then fuel to lift that fuel
             | and so on.
             | 
             | Since you have to have a burn to slow down and land you
             | have to carry extra fuel to recover. That's always going to
             | be the case, but starship is making strides towards
             | minimizing that as much as possible with belly flops and
             | chopsticks
        
             | alfiopuglisi wrote:
             | It's a limitation of the Falcon Heavy, the launcher used
             | this time. A future, more powerful one could do it while
             | being reusable.
        
               | tsimionescu wrote:
               | Sure, a bigger rocket could carry this particular payload
               | while being reusable. But for any rocket there will
               | always be payloads it can't carry while also having
               | enough fuel to land.
        
               | dotnet00 wrote:
               | That constraint can be significantly mitigated by in-
               | space refueling. Then it just becomes a matter of what
               | the rocket can lift into a stable orbit.
               | 
               | Edit: Not that this applies to any currently operational
               | rockets.
        
             | tsimionescu wrote:
             | It's limited by physics: if a reusable rocket can carry a
             | maximum payload of X tons, it can only be reused when it
             | carries a payload of X/N tons, and (1-X)/N as extra fuel.
             | How large X and N are of course depends on the rocket
             | design, but N is always going to be greater than 1.
             | 
             | So, for any rocket, flying it reusably is going to mean not
             | using the full capacity.
        
             | perihelions wrote:
             | It's an engineering tradeoff of payload vs. booster cost.
             | It's heavily one-sided for this launch--you get 4x more
             | payload to this interplanetary orbit with the expendable
             | Heavy vs. the reusable one [a].
             | 
             | Future launches with Starship, analogous to this one, would
             | refuel their upper stage in orbit to their full capacity,
             | so there would be no performance downside to recovering
             | boosters; you would need more launches, but they would all
             | be reusable.
             | 
             | [a] https://elvperf.ksc.nasa.gov/Pages/Query.aspx (I
             | queried for a high-energy orbit with a C3 of 42 km^2/s^2,
             | which I think is correct, or at least very close)
        
               | whamlastxmas wrote:
               | Also with starship launches only needing about a million
               | dollars in fuel, it makes a ton of sense to just launch
               | fuel to orbit versus sacrificing an entire ship
        
             | mmooss wrote:
             | It's limited by physics: Recovering the rockets requires
             | counteracting gravity, which requires energy. If the energy
             | is needed for something else - in this case for additional
             | propulsion - then it's not available for recovery.
        
             | ls612 wrote:
             | They traded off the expense of expending a whole Falcon
             | Heavy against the benefit of having additional delta-V to
             | get to Jupiter faster.
        
             | stetrain wrote:
             | You could build a larger re-usable rocket that could launch
             | this payload and still have margin for recovery, such as
             | the in-development SpaceX Starship.
             | 
             | However for this type of mission that would still leave the
             | question of "What if we skipped re-usability and paid more
             | to expend the launcher? Could we launch a larger payload
             | and/or get there faster?"
             | 
             | The trajectory for this mission was already a slower
             | transit time than the alternate plan of launching it on the
             | SLS rocket. I think for some missions that are infrequent
             | and targeting far-away destinations there will always be a
             | desire to maximize performance at the cost of reusability
             | on that singular launch.
        
         | pedrosbmartins wrote:
         | Not this time, only the payload fairing.
        
           | bryanlarsen wrote:
           | It's wild that the only thing they recover is the last thing
           | they jettison!
        
             | SonicScrub wrote:
             | Lightweight enough to be recovered via parachute system,
             | unlike the big heavy boosters which need thrust!
        
         | wlesieutre wrote:
         | Per NASA, no
         | 
         |  _> Because Europa Clipper needs a lot of energy to start it on
         | its interplanetary trajectory to Jupiter, the rocket for this
         | launch will be fully expendable, with the exception of a
         | recoverable fairing. This means that there will be no return of
         | first-stage boosters for this launch. Although SpaceX has flown
         | a fully expendable Falcon Heavy before, this is the first time
         | that NASA's Launch Services Program is launching a mission for
         | the agency with this Falcon Heavy configuration, though the
         | program has extensive experience now with both expendable as
         | well as reusable rockets. In addition to not recovering any
         | boosters, technicians removed components only needed for reuse
         | to increase the performance of the rocket, to launch the
         | largest planetary spacecraft NASA has ever developed and give
         | it the power it needs to travel to Jupiter._
         | 
         | https://blogs.nasa.gov/europaclipper/2024/10/14/nasa-launch-...
        
           | imglorp wrote:
           | That's awesome flexibility. I'm guessing that meant they
           | could omit landing legs, whatever powers them, and anything
           | to do with engine re-pressurization and restart. Any extra
           | fuel for boostback and landing can now go into S2 delta v.
        
             | wolf550e wrote:
             | They also removed the gridfins and their engines.
             | 
             | https://blogs.nasa.gov/europaclipper/wp-
             | content/uploads/site...
        
         | moffkalast wrote:
         | The suspiciously clean white areas on all three boosters where
         | the landing legs have been removed are good indicators of
         | what's planned.
        
       | throw0101c wrote:
       | Veritasium video on the Clipper probe/mission:
       | 
       | * https://www.youtube.com/watch?v=DJO_9auJhJQ
       | 
       | Real Engineering:
       | 
       | * https://www.youtube.com/watch?v=SzKkBOUvsAY
       | 
       | Probe named after the sailing ship design:
       | 
       | > _The etymological origin of the word clipper is uncertain, but
       | is believed to be derived from the English language verb "to
       | clip", which at the time meant "to run or fly swiftly".[2]_
       | 
       | * https://en.wikipedia.org/wiki/Clipper
        
         | stoneman24 wrote:
         | Not common but I have heard "moving at a fair clip" to describe
         | speed in commentary and conversation.
         | 
         | Perhaps the term hasn't quite died out.
        
       | payamb wrote:
       | ATTEMPT NO LANDING THERE.
        
         | imzadi wrote:
         | They haven't given me my monolith, so no contract established
        
       | DiscourseFan wrote:
       | can't wait to try some tasty Europafish
        
       | mmooss wrote:
       | ETA is 2030. Originally planned for a rocket (SLS) which would
       | have delivered the Clipper in ~3 yrs, but which was decided to be
       | not viable for the Clipper (with some lobbying suspected).
       | 
       | How much science is delayed by the extra 2+ years? Looking at the
       | 'project plan', is the Clipper's arrival (and delivery of data)
       | on the critical path for research? And how much research?
       | 
       | I'm picturing a lot of scientists and research projects waiting
       | an extra 2-3 years, and then all the research, follow-on
       | missions, etc. also delayed. Essentially, the decision might
       | shift everything in this field 2-3 years further away, and then
       | centuries from now human habitation of other planets is 2-3 years
       | later (ok, a bit exaggerated).
       | 
       | But seriously, maybe it's not on the critical path or doesn't
       | impact that much. Is anyone here familiar with the research?
        
         | vlovich123 wrote:
         | > In late 2015, Congress directed NASA to launch Europa Clipper
         | using the Space Launch System (SLS), NASA's massive moon
         | rocket.
         | 
         | > The SLS was still in development at the time, and would be
         | for a number of years to come. Delays with the powerful rocket,
         | and the need to dedicate at least the first three SLS vehicles
         | to launches for NASA's Artemis moon program, pushed Europa
         | Clipper's liftoff date into limbo. (SLS debuted in late 2022,
         | successfully sending the uncrewed Artemis 1 mission to the
         | moon.)
         | 
         | > The 2021 U.S. House of Representatives budget proposal
         | instructed NASA to launch Europa Clipper by 2025, and to do so
         | on an SLS "if available." Those two crucial words put the probe
         | on a path toward a commercial launch vehicle, which turned out
         | to be a Falcon Heavy.
         | 
         | So while the flight time may be longer, at least the entire
         | mission is derisked in that it was forced to get off the ground
         | instead of wait for an appropriate gap within the SLS's launch
         | capacity.
         | 
         | [1] https://www.space.com/spacex-falcon-heavy-europa-clipper-
         | lau...
        
         | Rebelgecko wrote:
         | Using a commercial launch vehicle reduced the cost quite a bit
         | (saved a billion on the vehicle itself and another billion by
         | not having to design the payload to pass SLS's much more
         | rigorous vibe checks). The $2b saved is about 10% of NASA's
         | annual budget. The next mission to Titan has a budget of around
         | $3b, for reference.
         | 
         | On top of that, there's no guarantee SLS would've actually been
         | able to launch on schedule. The program has had a lot of
         | setbacks, to put it lightly, and has only launched once so far
         | (6 years later than it's original ETA). There's additional
         | rockets in production but if it came down to it the manned SLS
         | missions would probably get priority for political reasons.
        
         | dotnet00 wrote:
         | > (with some lobbying suspected)
         | 
         | The lobbying was from the SLS side. Congress was set on forcing
         | Europa Clipper to fly on SLS regardless of technicalities and
         | only backed off because the Europa Clipper team made it clear
         | they'd want an additional $1B to make the spacecraft able to
         | handle the exceedingly rough ride SLS provides. They were
         | perfectly happy handing $2B of taxpayer money to Boeing, but
         | were unwilling to spend another $1B on science.
         | 
         | On top of that, it's worth considering that SLS wouldn't be
         | ready to fly right now anyway. As it stands, they can't even
         | manage to build one rocket per year, the Artemis-2 rocket has
         | already been delayed to next year, so, Clipper would've
         | launched 2-3 years later anyway.
        
           | mmooss wrote:
           | You don't think SpaceX did any lobbying? They just passively
           | stood aside? Look at this story, about SpaceX, via the
           | Project 2025 think tank's FOIA requests, searching for NASA
           | employees who has written things critical of SpaceX:
           | 
           | https://news.ycombinator.com/item?id=41757578
           | 
           | It's really hard to discuss any topic that brushes SpaceX
           | tangentially on HN. I asked about the research, not about the
           | rockets, but if one even mentions SpaceX in anything less
           | than glowing terms they get six (so far) responses re
           | rockets, all defending SpaceX, and not a mention of the
           | research.
           | 
           | NASA and SLS are actually the property of the people posting;
           | their mission is to serve all Americans. SpaceX is a private
           | business, whose mission is to serve only itself and, in the
           | practice of its owner's businesses, has zero regard for
           | everyone else.
           | 
           | In that context it's bizarre that people are fans of the
           | latter. In context of social media, where mass influence is
           | bought, it's perhaps what we'd expect - that's not NASA's
           | business.
        
             | nickpp wrote:
             | > private business, whose mission is to serve only itself
             | 
             | Any private business's primary mission is to serve its
             | customers - in order to even exist.
        
               | mmooss wrote:
               | By theory and - especially these days - by practice,
               | private business is there to enrich its owners.
               | 
               | One way it does that is to serve customers, another is to
               | manipulate, cheat, and squeeze them of every dime the
               | business can get, and then drop them for higher-margin
               | customers. Just look at modern business.
        
             | dotnet00 wrote:
             | >It's really hard to discuss any topic that brushes SpaceX
             | tangentially on HN. I asked about the research, not about
             | the rockets, but if one even mentions SpaceX in anything
             | less than glowing terms they get six (so far) responses re
             | rockets, all defending SpaceX, and not a mention of the
             | research.
             | 
             | Everyone's just pointing out the obvious fact that SLS
             | wasn't going to be able to do the mission on time or at
             | cost anyway, so the delays were happening regardless, and
             | Falcon Heavy was the only other option. You phrased your
             | question with the assumption that SLS was going to launch
             | on-time, added in the implication that SpaceX lobbied for
             | the launch and caused research to be delayed by a few
             | years, then decided to complain that everyone else was
             | being biased.
             | 
             | >NASA and SLS are actually the property of the people
             | posting; their mission is to serve all Americans. SpaceX is
             | a private business, whose mission is to serve only itself
             | and, in the practice of its owner's businesses, has zero
             | regard for everyone else.
             | 
             | SLS is the property of Boeing, another private business.
             | Its mission is to transfer vast sums of taxpayer money to
             | Boeing under a contract whose terms remove any expectations
             | of good performance and whose use in Artemis is legally
             | mandated by Congress for no technical reason. The NASA
             | Office of Inspector General has constantly been expressing
             | serious concerns over how bad of a deal SLS is for the
             | American people. We've also had genuine technological
             | progress held back because Congressmen wanted to transfer
             | money to SLS. Its ever inflating costs threaten actually
             | useful science programs every year. I don't see how anyone
             | who actually wants American leadership in space can support
             | it.
             | 
             | SpaceX, as you have noted, is also a private business. With
             | NASA being one of its biggest customers, they are obviously
             | beholden to NASA's desires. Unlike Boeing, who has
             | explicitly expressed their intent to refuse contracts which
             | properly hold the company responsible for under-performing,
             | SpaceX consistently insists on such contracts. Currently,
             | they provide most launch services to NASA and have saved
             | NASA billions over the years. They maintain a mutually
             | beneficial relationship, where NASA gains all sorts of
             | valuable data and capabilities from SpaceX's private
             | development efforts, and SpaceX gains business from NASA.
             | 
             | If you're dismissing this as a social media influence
             | thing, despite all the technical points presented to you,
             | then all that shows is that you were just concern trolling
             | in your original post and have no interest in actually
             | having your question answered.
        
         | jccooper wrote:
         | Well, Congress specified it to use SLS, since they were looking
         | for extra payloads. And then uncoupled it from SLS when it
         | became clear it couldn't even handle one extra payload.
         | 
         | NASA, wisely, always benchmarked the mission on Falcon Heavy,
         | and bailed from SLS as soon as they were allowed to.
         | 
         | Clipper on SLS was more of a "wouldn't it be neat" scenario
         | than the intended mission design.
        
         | why_at wrote:
         | I don't have any special insider information, but from what I
         | know about spaceflight I think we should be glad they used the
         | Falcon Heavy instead of SLS.
         | 
         | SLS has been consistently delayed pretty much every year since
         | its conception, most recently the Artemis 2 mission which was
         | supposed to fly this year is now delayed to next. It has only
         | flown one time, now two years ago. It's also an order of
         | magnitude more expensive than the Falcon Heavy with each flight
         | costing upwards of $2 billion.
         | 
         | My guess is if they had been stuck with SLS this mission would
         | not get to Europa until significantly later, if at all.
        
         | stetrain wrote:
         | This presumes that an additional SLS rocket would have been
         | completed and ready to launch in the same timeframe as this
         | launch on Falcon Heavy. From what I have seen of the SLS
         | program I think that is an unlikely scenario.
        
       | d_silin wrote:
       | Damn, I am impressed how nonchalantly the flagship NASA mission
       | was using the reused boosters, dirty from soot.
        
         | grecy wrote:
         | NASA prefer them now, as they're "flight proven".
         | 
         | They're using them to launch astronauts now too.
        
         | ballooney wrote:
         | Nothing nonchalant about it. There was a stringent
         | qualification process.
         | 
         | The time between boosters first being reused in Falcons and
         | this mission is the same as the time between JFK's 'we choose
         | to go to the moon' speech and the actual moon landings.
        
       | proee wrote:
       | Cost of the Europa Clipper program is around $4-5 billion. Can
       | anyone in the industry shed some light on why these programs are
       | so expensive?
        
         | dgrin91 wrote:
         | Because it's one shot, must work stuff. They don't build this
         | type of equipment often (really ever) because it's all bespoke
         | to this mission. That means they need to build, verify, test,
         | etc and it all has to work first time because there is only 1
         | shot (over a 1 month period) for the launch window
        
         | hydrogen7800 wrote:
         | I worked on one component of the spacecraft which was a
         | derivative of something we've built may times before. However,
         | the test program was entirely unique to Europa Clipper, and
         | most of the cost was in this bespoke testing. The use of a
         | "heritage" component served mostly to lower risk; it did not
         | save much cost overall.
        
           | consumer451 wrote:
           | Oh cool, someone that actually worked on it!
           | 
           | I was just thinking about how much pressure there must be on
           | everyone involved in Discovery Class missions. People's
           | entire professional careers, billions of dollars, so much at
           | stake!
           | 
           | Is the pressure something significant, or is it spread across
           | so many people that there is little trouble sleeping at
           | night?
        
             | mandevil wrote:
             | The one that gets to me is the Huygens part of the Cassini-
             | Huygens mission. Cassini was launched October 15th, 1997,
             | Huygens separated from the Cassini carrier on December 25th
             | 2004, and landed on Titan on January 14th, 2005. So it was
             | in space for over 7 years before it got it's 90 minutes of
             | time on the surface. That was actually towards the upper-
             | end of expected lifetime on Titan- somewhere between 30-90
             | minutes was the expected lifetime of the lander(1). So you
             | build and test and test and test (2) for years before
             | launch, then the probe travels for seven years in outer
             | space, and then it gives you an hour and a half of data and
             | that's it. Your entire life for ... 15 years? Resolved in
             | 90 minutes. On the shorter end of probe lifespan, it would
             | have died before the first signal even reached Earth!
             | 
             | 1: Officially I believe the expectation was "3 minutes" but
             | that was a deliberate under-promise so that a success could
             | be declared as long as they got any message at all from the
             | lander on the surface: I have second-hand accounts that 30
             | minutes was what the scientists considered the minimum.
             | 
             | 2: Even with all that testing, disaster almost struck. It
             | wasn't until after the launch that someone realized even
             | all of this testing had missed something important. The
             | radio communications between Cassini and Huygens would be
             | affected by the Doppler shift of Huygens hitting Titan's
             | atmosphere, which would be unpredictable changes to
             | velocity. After launch they had to rejigger when Huygens
             | would be launched to a time when the signals would be
             | perpendicular to the direction of travel so the shift
             | wouldn't affect the radio waves so much that the Cassini
             | receiver firmware (which could not be modified after
             | launch) could still detect the signals. And also with all
             | of that testing, ESA's instructions to the Cassini probe
             | missed turning on one channel on the receiver and so half
             | of the pictures that Huygens transmitted had nothing
             | listening in and were lost.
        
               | consumer451 wrote:
               | Thanks for that. It made me wonder: who was it? Were they
               | in the shower, did they awake from a nightmare?
               | 
               | Here is an HN post from 2014, "How a Swedish engineer
               | saved a once-in-a-lifetime mission to Titan (2004)" [0]
               | 
               | Since the link has rotted away, here is the archive link
               | to the IEEE story. [1]
               | 
               | [0] https://news.ycombinator.com/item?id=7472495
               | 
               | [1] https://archive.is/3oj6P (archive.org is still not
               | working reliably)
        
               | JumpCrisscross wrote:
               | > _Your entire life for ... 15 years? Resolved in 90
               | minutes_
               | 
               | I ultimately decided against pursuing a career in
               | aerospace engineering after talking to engineers who
               | worked a similar time frame on a project only to watch it
               | get killed in 30 seconds' debate in Congress.
        
             | hydrogen7800 wrote:
             | >Is the pressure something significant, or is it spread
             | across so many people that there is little trouble sleeping
             | at night?
             | 
             | When you are on contract for something, you deliver to the
             | contract, and are done when you successfully meet the
             | customer's requirements. So in that sense you don't have
             | the same exposure to the program risks.
             | 
             | However, I've been part of one-off science missions before,
             | and there is a different feeling beyond the contract
             | obligations, though it's certainly abstracted through the
             | many layers of sub-, sub-contracts.
        
           | mandevil wrote:
           | And can introduce unusual failure cases for these bespoke
           | missions. Mars Observer was lost in flight to Mars three
           | decades ago, probably because of the inappropriate reuse of a
           | satellite rocket engine. (1) The space environment out around
           | Jupiter is really quite different from the environment that
           | the JWST is facing around E-S L2 or what the Parker Solar
           | Probe is facing right near the Sun. Even if the component is
           | spec'd to handle the environment, you need to have actual
           | educated humans (read: expensive labor) determine what those
           | conditions will be, and then verify that the part will meet
           | it, and that's where the money goes- to pay all of those
           | humans.
           | 
           | If you built even 15 Europa Clippers the cost per-item would
           | come down enormously (because all of those people's work
           | could be re-used), but since the 1970's NASA has not had the
           | budget for multiple probes per missions. So every mission is
           | bespoke, and has to be done again completely from scratch.
           | 
           | 1: The engine was normally used for circularizing the orbit
           | of a geosynch comm satellite, so within a few hours of
           | flight. For doing a Mars Insertion burn it needed to sit
           | fueled for months in outer space, which was not appropriately
           | tested, and probably the fuel tank exploded in flight because
           | of that.
        
             | quotemstr wrote:
             | Yeah. I'm surprised that we don't have a standard deep
             | space probe bus by now in at least serial production, at
             | least for orbiters if not landers, rovers, and such.
             | 
             | Each mission has unique requirements, but since payload
             | mass costs are coming down, ISTM it should be possible to
             | create a standard buss that meets most requirements most of
             | the rime, even if it's heavier than a bespoke effort for
             | any one mission.
        
               | accrual wrote:
               | There are somewhat standard busses. Though you're
               | correct, many use custom busses for their specific
               | missions.
               | 
               | https://en.wikipedia.org/wiki/Comparison_of_satellite_bus
               | es
               | 
               | For example, the SSL 1300 apparently has hosted 118
               | satellites so far:
               | 
               | https://en.wikipedia.org/wiki/SSL_1300
               | 
               | Though maybe the distinction between "satellite" and
               | "spacecraft" bears importance here.
        
               | mandevil wrote:
               | For things in Earth orbit (LEO all the way up to GEO) we
               | do have some fairly worked out buses that can keep
               | commercial missions done on budget within the fairly well
               | developed parameters of commercial up to GEO. Have,
               | honestly, since the 1980's. Multiple companies from
               | multiple countries have demonstrated this, there is a
               | competitive market for commsats and earth observing
               | satellites (the only two markets where business cases
               | really close). If you are doing science from LEO you can
               | probably re-use a lot of components from those markets.
               | 
               | For exploration missions and anything in deep space
               | (basically, beyond Lunar Orbit) people have kicked around
               | ideas for common buses, there have been plenty of
               | proposals, but no one seems to have enough value in them
               | to be the third or fourth user of one- everyone has found
               | it better to start from scratch than use someone else's
               | bus design. It is possible if there was a sustained,
               | focused effort at one kind of project, say, something
               | where Mars orbiter launches were guaranteed every 26
               | months for more than a decade, that the investment in a
               | common bus might pay off. But as long as we are bouncing
               | between Mars, Jupiter, Pluto/KBO's, E-S L2, and inside
               | Mercury's orbit, it just isn't actually reusable.
               | 
               | Just as one point, until the past few years everything in
               | the outer planets had to be RTG powered, which requires a
               | totally different design than something solar. It was
               | only with Juno (and now the Europa Clipper) that solar
               | has been demonstrated for outer planets at all, and it is
               | still not exactly a design you'd have off the shelf, nor
               | would the power design you'd want for outer planets solar
               | be at all similar to the design you'd want for inner
               | planets solar. The same is true for comms, for thermal
               | management, for rad-hardening, etc.
        
             | dom96 wrote:
             | > So every mission is bespoke, and has to be done again
             | completely from scratch.
             | 
             | Is there room here for making things more reusable? For
             | example, instead of creating one big satellite with tens of
             | instruments, how about they create 10 satellites with one
             | instrument each? or would that still be too bespoke to
             | lower the cost per item?
        
               | philistine wrote:
               | While we now live in an era of abundant rocket launches,
               | it used to cost far more to launch with very few launches
               | per year.
               | 
               | The whole strategies of exploration haven't shifted yet
               | to this new paradigm. Hopefully NASA starts making
               | smaller probes and launching them far more often.
        
               | mandevil wrote:
               | Europa Clipper is literally the largest thing ever
               | launched to the outer planets (so big that Falcon Heavy
               | can't be reused for this mission, they have to throw it
               | all away in order to get every last jot of performance
               | out of the rocket- so this is not an "abundant rocket
               | launches" situation- this is a fully expendable rocket
               | just like an Atlas V). And the size is not for fun, but
               | because going close to Europa (the entire point of the
               | mission) means going through the second strongest set of
               | EM and radiation belts in our solar system. Even with
               | this size- meaning it can have a lot more shielding than
               | normal- the probe can only survive a few months of the
               | radiation from Jupiter's van Allen belts. The plan is to
               | break that few months of exposure up over about four
               | years of calendar time, by having it do highly elliptical
               | orbits so it stores a lot of data during a close flyby of
               | Europa and then transmits that all back to Earth while it
               | is far outside of Jupiter's radiation storm, then it can
               | head back down and collect more data. And that lengthy
               | transmission time is because it is sending information
               | from so far away- and has so little juice that the
               | effective bandwidth is tiny.
               | 
               | It is possible for a swarm of small satellites to fill
               | niches in space exploration. Closely studying Europa
               | isn't really one of them with today's technology.
        
           | throwup238 wrote:
           | There's also politics at play. Public space agencies need to
           | keep the absolute number of failures down to keep funding
           | flowing, even if it costs absurd amounts to do it due to
           | rapidly diminishing returns. This is especially important to
           | flagship missions.
           | 
           | When I took Ae105 at Caltech, the NASA MSL project manager
           | explained it like this (I remember the numbers he used
           | clearly): a mission might cost $500 million with an 80%
           | chance of success, or they can spend twice as much to
           | increase the chance of success to 95% by investing a lot more
           | in upfront testing and R&D. Now, the smart thing to do -
           | given a billion dollar budget - is to take that first option
           | because if it fails you can try again and the probability of
           | _both_ attempts failing is only 4%, compared to 5% for the
           | expensive single mission. Then you've got an 80% chance of
           | having $500 million left over for a different mission.
           | 
           | The public and decision makers react irrationally to _any_
           | failure, putting funding for other missions and the entire
           | program in jeopardy. NASA and ESA have to make some extremely
           | suboptimal decisions to make sure that funding doesn't get
           | catastrophically cut.
           | 
           | The above is the example the instructor used to easily
           | illustrate his point but he said the real numbers are even
           | more stark. Often times the cost savings of just building a
           | second copy of the payload along with the first means it
           | costs $600 million for the first attempt, and only $200
           | million for the second (the cost of the launch vehicle and
           | keeping people on staff), saving hundreds of millions
           | overall.
        
             | frickinLasers wrote:
             | It's really frustrating that there's not a way to educate
             | the public on simple concepts like this. You'd think the
             | out-in-the-open development approach of SpaceX, for
             | instance, would make it blatantly obvious how much money
             | they're saving by permitting failure...yet the news
             | continually spins their less-than-perfectly successful test
             | launches as undesirable. And space spending is perhaps one
             | of the least consequential areas of government where this
             | failure of the herd to comprehend reality applies.
        
               | downvotetruth wrote:
               | The public are smarter than you give them credit for. For
               | the most part space missions are contests between
               | governments and those governed with science as a
               | consolation price. If you are part of team A do you want
               | to have to come up with reasoning on why you lost? No.
               | Does anyone care if a billionaire's toy gets blown up?
               | No. The obvious choice to eliminate all risk would be not
               | to play, but that is not an option; the other is to delay
               | and delay some more. Thus, SLS.
        
               | smileson2 wrote:
               | It's easy to imagine 3-4 years of projects failing and
               | someone grandstanding about it, space exploration is a
               | pointless endeavor to a lot of people
        
             | exmadscientist wrote:
             | > The public and decision makers react irrationally to any
             | failure, putting funding for other missions and the entire
             | program in jeopardy. NASA and ESA have to make some
             | extremely suboptimal decisions to make sure that funding
             | doesn't get catastrophically cut.
             | 
             | Which, incidentally, is one of the key reasons SpaceX has
             | had the success they have: they're set up to handle failure
             | and avoid this politics. How many Starships have blown up?
             | If Starship were a NASA program, how many explosions ago
             | would it have been cancelled? And yet this approach to risk
             | is pretty effective!
        
               | mmooss wrote:
               | Isn't that partly or largely due to Musk's influence?
               | Like many powerful influencers, Musk can reliably rally
               | supporters to even an unreality.
               | 
               | Compare the responses to a failure by Boeing or SLS and
               | to a failure by SpaceX.
               | 
               | Also, SpaceX hasn't had a serious non-experimental
               | failure yet (?). I'm sure their PR is preparing for that
               | eventuality, but when non-fans are upset over a bad
               | outcome and then learn about the risk tolerated, they
               | will swing from admiring risk to condemning it. Imagine
               | the Congressional committees.
               | 
               | Even if SpaceX is super-conservative when flying humans
               | (which we shouldn't assume - cultures tend to be
               | consistent), if someone dies then all that risk-seeking
               | behavior will be attacked.
               | 
               | (To be clear, as long as SpaceX can manage risk in
               | production - i.e., with high-value payloads such as
               | people and NASA flagships - I think they and everyone
               | else should use risk efficiently.)
        
               | 15155 wrote:
               | > Also, SpaceX hasn't had a serious non-experimental
               | failure yet
               | 
               | SpaceX had an explosive failure in 2016 with a commercial
               | payload onboard.
        
               | mmooss wrote:
               | Thanks. How valuable was the payload?
        
         | kens wrote:
         | I was curious, so I looked up the budget. Development of Europa
         | Clipper cost about $2.5 billion of which $1.1 billion was the
         | spacecraft, $475M was payload, $200M was the launch vehicle
         | (about $230M saved by not using SLS), $160M for ground systems,
         | $60 M for testing. Formulation of Europa Clipper cost $1.2
         | billion. Operating it will cost about $80M per year.
         | 
         | Details on the Europa Clipper budget are at
         | https://www.nasa.gov/wp-content/uploads/2023/03/nasa-fy-2024...
         | 
         | (Edit: fixed billion/million typo)
        
           | Deukhoofd wrote:
           | > $200 billion was the launch vehicle
           | 
           | Million I'd assume?
        
           | frickinLasers wrote:
           | > (about $230M saved by not using SLS)
           | 
           | Since SLS launches are now upwards of $2B per launch by some
           | estimates, how does this math work? Wikipedia also suggests
           | $2 billion saved.
           | 
           | https://en.wikipedia.org/wiki/Space_Launch_System#Europa_Cli.
           | ..
        
             | philistine wrote:
             | I bet you it's what the project would have been charged by
             | the SLS program, but SLS would have lost a billion by
             | providing a launch.
        
             | kens wrote:
             | In the NASA budget, -$230M is the "change from base year
             | estimate" for the launch vehicle. In other words, the
             | launch vehicle ended up being less than half the price of
             | the initial budget estimate. (This is unusual; almost
             | everything goes up from the initial budget.) Originally,
             | congress mandated that Europa Clipper use the SLS to
             | launch. But after vibration problems turned up with SLS, it
             | would take $1 billion to redesign the Clipper. They say the
             | SLS would have cost $1 billion for the launch vehicle. So I
             | think the way the math works out is that SLS rocket cost
             | much more than originally budgeted ($800M more?) and it
             | would have cost another $1 billion to redesign Clipper. So
             | abandoning SLS saved $230 million compared to the original
             | budget but saved $2 billion compared to what SLS would have
             | ended up costing.
        
         | spywaregorilla wrote:
         | Building a ship containing delicate sensors that needs to get
         | into space, arrive at the target, and beam back measurements on
         | the first try with a very low tolerance for error is hard.
        
         | Analemma_ wrote:
         | On Earth, it's cost-efficient to build things with a reasonable
         | "bathtub curve" failure rate because they can be repaired or
         | (if a consumer product) replaced under warranty. Neither of
         | these are an option in one-off space projects: everything has
         | to be built to ~100% initial reliability, which makes
         | everything much more expensive.
         | 
         | In theory falling launch costs will eventually mean maybe we
         | can make space science missions more disposable so a loss from
         | random failure is no big deal, but we're not quite there yet.
        
       | frinxor wrote:
       | https://en.wikipedia.org/wiki/Europa_Clipper#Launch_and_traj...
       | 
       | really cool to see the trajectory:
       | 
       | - earth mars gravity assists
       | 
       | - complex trajectory around jupiter and its moons
        
       | supplemental wrote:
       | For a moment I though this is European space agency sending a
       | rocket :'(
        
       | mmooss wrote:
       | I love JPL's straightforward bio:
       | 
       | https://www.nasa.gov/jpl/jet-propulsion-laboratory-history/
       | 
       | "JPL led the U.S. into space with Explorer 1, the first U.S.
       | satellite, and joined NASA shortly after the agency formed in
       | 1958. JPL spacecraft have flown to every planet in the solar
       | system, the Sun, and into interstellar space in a quest to better
       | understand the origins of the universe, and of life."
       | 
       | Not many organizations can say that: _We 've flown to every
       | planet in the solar system._ Wow. (And of course, they've done
       | more than that.)
        
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