[HN Gopher] Why is it so hard to pull off a lunar landing?
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Why is it so hard to pull off a lunar landing?
Author : pseudolus
Score : 95 points
Date : 2023-04-29 11:15 UTC (11 hours ago)
(HTM) web link (www.nature.com)
(TXT) w3m dump (www.nature.com)
| Dah00n wrote:
| It is sad that every time there is a discussion online about
| something like this it always ends up with some anti-USSR / pro-
| US talk.
| spaceman_2020 wrote:
| What was different about the Apollo missions that they were so
| overwhelmingly successful, but similar efforts fail today?
| azlev wrote:
| Total Apollo workforce: 400,000.
|
| https://www.bbc.com/future/article/20190617-apollo-in-50-num...
| cubefox wrote:
| The most important difference is probably the budget.
| m4rtink wrote:
| Couple dozen Ranger and Surveyor probe craters to get the
| landing technology right.
| nanumbat wrote:
| Yes on Ranger, however the first Surveyor completed a soft
| landing and returned image data.
| T-A wrote:
| _An unwelcoming view glared at Armstrong. Where the orbital
| maps indicated a smooth plain, there was instead a vast crater
| field and collections of truck-sized boulders. Flying manually
| and low on fuel, Armstrong leveled off and searched for a
| smooth spot._
|
| https://www.space.com/26593-apollo-11-moon-landing-scariest-...
| aflag wrote:
| The budget, for one. It was 2-3% of the GDP at the time. These
| commercial efforts have nothing remotely close to that. Also
| failure was seen as a bigger deal for all involved (due to the
| soviet threat). So, they'd rather waterfall the hell out of
| that program rather than fail and do things iteratively. I'm
| sure these commercial projects will eventually succeed. But it
| takes time.
| pseg134 wrote:
| Why do you express the budget as a percentage of GDP instead
| of inflation adjusted dollars?
| aflag wrote:
| To better represent how big of an effort it was. A non-
| trivial part of the economy was dedicated to get that
| project working. I think that is a better representation of
| the effort.
| spaceman_2020 wrote:
| Wow, 2-3% of the GDP is massive. I didn't realize it was such
| a well-funded effort.
| williamDafoe wrote:
| I am wondering if 2-3% of GDP is accurate? 2-3% of GDP was
| spent on 0.2% of the population ... Really?
| chrisweekly wrote:
| Fun tangent: this moon lander game was posted here on HN
| recently: https://ehmorris.com/lander/
| uguuo_o wrote:
| Why is it so hard? Plume-surface interaction plays a major role
| during the landing sequence. Most projects "test,test and more
| test" like the ones mentioned in the article, but they clearly
| have no idea how unforgiving the environment is. When the vehicle
| gets closer to the surface, the engine exhaust gets redirected
| upwards, accelerating regolith to ~ 1km/s speeds. Any sensitive
| hardware that is hit can easily be taken out. Additionally, the
| closer the vehicle gets to the surface the more difficulty
| landing sensors will have in looking through the induced regolith
| cloud.[0] NASA has been studying the problem through experimental
| and computational campaigns for a long time, but just recently
| has put significant resources into understanding PSI on extreme
| environments.
|
| Edit: reference
|
| [0]
| https://www.nasa.gov/directorates/spacetech/game_changing_de...
| mjevans wrote:
| Also see the most recent first SpaceX Starship launch attempt.
| Widely accepted current theories about likely failure mode root
| cause involve exactly this sort of thrust ground interaction
| kicking up debris.
|
| I am a huge proponent of sending robots first, to build safer
| landing and launch structures, possibly also bases or better
| places to situate bases.
| WalterBright wrote:
| > Compared with Earth, for example, the Moon has reduced gravity,
| very little atmosphere and lots of dust.
|
| But no weather. Weather is an enormous risk factor for Earth
| landings.
| 7373737373 wrote:
| What stands out to me is:
|
| > Even if a lander makes it to the vicinity of the Moon, it still
| has to navigate its way down to the surface with no global-
| positioning satellites for guidance
|
| Was/is such a constellation ever planned? If not, why - due to
| the difficulty orbiting the moon?
| [deleted]
| m4rtink wrote:
| Moon is indeed hard to orbit (without constant course
| corrections) due to its lumpy gravitational field:
|
| https://en.m.wikipedia.org/wiki/Mass_concentration_(astronom...
| mjevans wrote:
| Why not just send robots to build some triangulation towers
| on the surface instead?
| williamDafoe wrote:
| Cruise missiles have an incredibly good terrain following
| navigation software - I don't think it's hard to navigate
| without GPS people get fat dumb and lazy because of GPS...
| bitL wrote:
| Frankly, why is it so hard? The article doesn't really show
| anything outside dust playing role in the very final stage but
| most landings failed higher above ground. These days we even have
| lasers to instantly detect distance to the ground that could be
| incorporated real-time to thruster output. There is almost no
| atmosphere for friction so basic Newtonian mechanics should be
| able to make a decent landing. Orbital mechanics is also out of
| the question near the ground. Why is this still an unsolved
| problem?
| khendron wrote:
| > There is almost no atmosphere for friction so basic Newtonian
| mechanics should be able to make a decent landing
|
| Actually, I think that is the one of the biggest challenges. No
| atmosphere to slow you down means you have to rely entirely on
| rockets to slow down from orbital speeds to zero.
| HarHarVeryFunny wrote:
| How many complex machines (or complex anything) are going to
| work first time?
|
| Most things require an iterative loop of testing, fixing and
| refinement.
|
| The trouble with landing on another planet (with different
| gravity, atmospheric density, etc) is that there's no real way
| before you get there, therefore first attempts are extremely
| likely to fail.
| joshuahedlund wrote:
| Still going to have margins of error with both the measurements
| and the corrections, right? If those margins are higher than
| what the Moon forgives...
| rbanffy wrote:
| Fully autonomous landing in unknown surfaces is still pretty
| difficult. Still, the Moon should be more forgiving than the
| Earth - no wind, lower gravity...
| krisoft wrote:
| But also, here on earth you go to your backyard and try
| your landing as many times as you want. While with the moon
| you have simulations and models of various fidelity.
| csunbird wrote:
| A celestial body with an atmosphere: Very easy to land but
| incredibly hard to take off from.
|
| A celestial body with no atmosphere: Extremely easy to take
| off from, but very hard to actually land.
| m4rtink wrote:
| No atmosphere - need to brake all of the velocity
| difference with engines & can't use aerodynamic surfaces or
| parachutes.
|
| On a body with atmosphere you can essentially just drop a
| payload up to some maximum size with a proper heat shield
| and a parashute and it will end up (somewhere) on the
| surface in one piece.
|
| On an atmosphere less body you essentially need to run
| precisely controlled flight all the way to touchdown.
|
| Everything has tradeoffs. :-P
| rbanffy wrote:
| > need to brake all of the velocity difference with
| engines
|
| Engines are well understood. With enough propellant one
| can gently hover down at 1 cm/s from 1km. No atmosphere
| also means few surprises.
| messe wrote:
| A thin atmosphere like mars can make it worse. The actual
| amount of braking you get is a bit unpredictable, and the
| size of the aerodynamic surfaces you need to make a
| significant impact can use up quite a bit of your mass
| budget (example: despite the size of the
| Perseverance/Curiosity parachutes, they still needed a
| sky-crane for final touchdown).
| T-A wrote:
| > but most landings failed higher above ground
|
| AFAIK there have only been two attempts by private companies.
|
| SpaceIL's crash in 2019 seems to have been caused by a
| premature engine shutdown due to a faulty IMU [1].
|
| iSpace's attempt seemed to go well until the very end, when
| contact with the lander was lost. Their status update from
| April 26 suggests that also their engine may have shut down
| prematurely: "engineers monitored the estimated remaining
| propellant reached at the lower threshold and shortly afterward
| the descent speed rapidly increased" [2].
|
| If this turns out to be the case, the ultimate culprit may be
| faulty altimetry.
|
| > These days we even have lasers to instantly detect distance
| to the ground that could be incorporated real-time to thruster
| output.
|
| Yes, but lasers don't work well through dust clouds, and
| throttling rocket engines is hard. You can't smoothly reduce
| thrust all the way to 0; even with a sophisticated design,
| there is a cutoff at something like 20% [3]. So you need to
| plan ahead, shut down the engine before touchdown and hope that
| you don't end up hitting a stray boulder - which is all it
| might take to tip over and bury your antennas in regolith.
|
| [1] https://spacenews.com/spaceil-says-chain-of-events-led-to-
| cr...
|
| [2] https://ispace-inc.com/news-en/?p=4655
|
| [3] https://en.wikipedia.org/wiki/Rocket_engine#Throttling
| WalterBright wrote:
| > early indications suggest that this week's ispace failure could
| have been caused by the lander running out of propellant just
| before it touched down
|
| I practiced a lot with the Lunar Lander game in the 1970s. The
| trick is to let it fall until the last second, then hit the
| thrusters full blast to hit 0V as it hits the surface.
|
| Burn too soon, and you run out of propellant and crash.
| cubefox wrote:
| > Only three entities have successfully soft-landed on the Moon
| -- the government-funded space agencies of China, the Soviet
| Union and the United States. And only China has done it since the
| 1970s and on its first attempt.
|
| This sounds as if the journalist tries to downplay the fact that
| NASA managed to do it a) first, and b) actually landed humans on
| the moon, not just unmanned vehicles. The only thing which makes
| it less impressive is the enormous budget of the Apollo program.
| Freire_Herval wrote:
| The sentence is just a factual statement. 3 agencies have done
| it. That is fact.
|
| The sentence did mention china has done it on the first attempt
| which is also factual and relevant to context. The article is
| about moon landings and associated failures.
|
| As for the Apollo program everyone knows about it. There's no
| point in regurgitating obvious facts.
| sidlls wrote:
| It's only relevant to context if it also includes the context
| in which the event occurred: China's first attempt is not a
| notable achievement in the same way the first successful
| landing after many failures is. I really hate these
| sinophiles' attempts to elevate China into some super-
| awesome, super-intelligent master race.
| Dah00n wrote:
| >I really hate these sinophiles' attempts to elevate China
| into some super-awesome, super-intelligent master race.
|
| Please don't do this. You are seeing things in the text
| that isn't there and you seem to do the same just the other
| way around. It reads anti-chinese / racist.
| cubefox wrote:
| He was just arguing against (what he perceived as)
| excessive sinophilia.
| Freire_Herval wrote:
| [dead]
| messe wrote:
| > China's first attempt is not a notable achievement in the
| same way the first successful landing after many failures
| is.
|
| Landing on the first attempt is pretty impressive in
| itself, given the difficulty in landing at all is.
|
| > I really hate these sinophiles' attempts to elevate China
| into some super-awesome, super-intelligent master race.
|
| ...I'm sorry, what the fuck are you talking about?
| yshklarov wrote:
| You could be right, but the way I read it is that those are
| things that everyone already knows, so there is no point in
| spelling them out.
| so-and-so wrote:
| Thought it was the soviets to first "land" a ship on the moon.
| Remember they had a lot of internal dicussions on if the Moon
| had a solid surface.
| euroderf wrote:
| The Apollo 11 crew was ready to immediately take off again if
| the lander's legs began sinking deeply into dust.
| jwilk wrote:
| https://en.wikipedia.org/wiki/Luna_9
|
| > _On 3 February 1966, the Luna 9 spacecraft became the first
| spacecraft to achieve a survivable landing on a celestial
| body._
| cubefox wrote:
| Oops. But too late to delete the comment now...
|
| By the way, it got 7 upvotes despite being factually
| incorrect.
| ncphil wrote:
| But a lot of US govt programs from that era spent a lot more
| money, and didn't deliver such impressive results: if they
| delivered at all.
| cubefox wrote:
| At least the Manhattan project was similarly impressive.
| f6v wrote:
| It'd be much easier if all we care was humanity's achievements.
| Freire_Herval wrote:
| Darwinistic tendencies will always be part of human behavior,
| it is ingrained in our biology.
|
| People will be competitive, and they will form groups and
| take sides and compare technological achievements.
| amrocha wrote:
| NASA didn't do it first, the USSR did. And the only reason they
| didn't land people on the moon first too is because their
| country was falling apart and they reduced investment in their
| space program.
|
| You're the one downplaying actual history.
| williamDafoe wrote:
| It took 12 attempts to land a robot on the moon for the USSR.
| Their heavy booster program was in shambles. They literally
| never developed anything close to as powerful as Saturn V (5m
| pounds of thrust). They would be lucky not to crash 12 human
| vehicles on the moon. Leading for the first 5 miles of a
| marathon doesn't make you the winner!
| cubefox wrote:
| I think their N1 rocket was similar and pretty far in
| development before it was cancelled.
| mustacheemperor wrote:
| The N1 rocket was intended to be similar but how far
| along it really was to completion seems questionable to
| me. I'm not a rocket scientist, but my understanding is
| the first stage was not statically tested and the
| complete rocket failed in the first stage on each of its
| four tests - one of which caused a gigantic explosion in
| the launch complex visible from over 20 miles away. If
| anyone with deeper rocket history expertise can weigh in
| I'd be interested to know how feasible an average
| historian would consider the successful completion of the
| N1 if it had continued to be funded.
| amrocha wrote:
| In the space race's case, they were leading in literally
| all practical and utilitarian aspects during the entire
| race, then they won the race, called it quits, and then the
| USA moved the goalposts and crossed them.
| WalterBright wrote:
| They could not get their moon booster rocket to reliably
| work, and that ended their moon shot program.
|
| Saturn V had the same problems (dynamic instability)
| which nearly destroyed it. It just barely worked.
| Dah00n wrote:
| >the only reason they didn't land people on the moon first
| too is because their country was falling apart
|
| My interpretation of the history of the USSR space program is
| that they more often than not went the hard way and used
| remote controlled/preprogrammed vehicles not because it was
| easier but because it was hard (sorry). I fail to see how
| landing people on the moon is a bigger achievement than if it
| was done by remote control in a time with, well, hardly any
| computer power at all. In my opinion this is part of the
| rewrite of the history of the space race to an alternative
| version where the goal was actually landing a man on the moon
| and not a moving goal post that changed every time something
| new was achieved.
| amrocha wrote:
| I don't disagree with you, the goalposts were always being
| moved by the country that lost the last stage, usually the
| USA.
|
| I also think there's a case to be made that, given their
| history of success and expertise, they could have also
| landed a man on the moon first if things had gone
| differently.
| neom wrote:
| If you wanna see the disappointment in the control room, here is
| the video:
|
| https://www.youtube.com/live/CpR1UUnix3g?feature=share&t=428...
|
| Scrub to 1:11:20
|
| And at 1:35:33 the folks in the background look like they're
| holding back tears.
| fuzzfactor wrote:
| >the United States and the Soviet Union were racing to land
| there, they crashed spacecraft after spacecraft before each
| finally succeeded in 1966. The government space agencies were
| able to learn from each landing attempt.
|
| Roger.
|
| >Today, by contrast, private companies are expected to repeat
| these successes, without government resources and without
| lessons gleaned from many failed and successful missions
|
| Misplaced expectations.
|
| They're going to _need_ more crashes.
|
| >the folks in the background look like they're holding back
| tears.
|
| This was not in the background when NASA astronauts were
| tragically lost before they got to the moon the first time.
|
| I expect anyone to repeat these failures until they have enough
| lessons learned themselves.
|
| >why is it so hard to pull off a lunar landing?
|
| Mother Nature is a bitch.
| mulmen wrote:
| > This was not in the background when NASA astronauts were
| tragically lost before they got to the moon the first time.
|
| I don't follow. Are you suggesting NASA mission control
| didn't mourn the loss of Chaffee, Grissom, and White?
| hgsgm wrote:
| It was in the foreground.
| fuzzfactor wrote:
| Definitely what I had in mind.
|
| The whole world was heartbroken as awareness was
| universally raised about remaining risks even after such
| extensive and successful efforts had intentionally and
| brilliantly greatly reduced the possibilities.
|
| Lurking risks still exist and unforseen failure modes
| remain as defined.
|
| Space Shuttles were not fatality-free either.
| sidlls wrote:
| On the one hand we have people lauding SpaceX/Musk as super
| geniuses able to achieve great feats without the supposed
| waste and largesse of the government, and on the other we
| have the same group wringing their hands when expectations
| are set based on their gushing praise.
| fuzzfactor wrote:
| "Naturally", it can take so much time to accomplish
| something working _with_ nature, time is one of the most
| likely natural forces to cause expectations to exceed
| accomplishments or even possibilities.
|
| And when nature is working _against_ you . . .
| eql5 wrote:
| Related: https://www.youtube.com/watch?v=KpuKu3F0BvY
| jmyeet wrote:
| Many of us have an overly simplistic view of orbital mechanics
| that fall well short of how it works in the real world. Take the
| example of India's failed Vikram lander [1]:
|
| > The official said that predicting orbits below 50 km is very
| tricky and usually they are estimated with an accuracy of
| plus/minus 1 km. If the lander`s predicted height was at 30 km,
| the actual orbit height may remain anywhere between 29 to 31 km.
|
| > Similar will be the error in horizontal direction. Such errors
| occur as local gravity varies widely due to large variation of
| density of mountains and plains.
|
| Newton's gravity equations deal with bodies like the Moon as
| having uniform mass. That's not he case and it matters.
|
| Fun fact: China's Three Gorges Dam slowed down the Earth's
| rotation by 0.06 microseconds per day [2]. That's actually not a
| big deal because the rotation has variance all of its own from
| tides, weather, etc.
|
| So even if you had a density map of the Moon you'd still have to
| account for variance added by rotational variation.
|
| [1]: https://www.zeebiz.com/india/news-on-indias-vikram-lander-
| di...
|
| [2]: https://www.kinetica.co.uk/2014/03/27/chinese-dam-slows-
| down...
| krisoft wrote:
| > Newton's gravity equations deal with bodies like the Moon as
| having uniform mass.
|
| Let's not make a joke of ourselves. Newton's gravity equations
| deal perfectly well with non uniform masses. You just need to
| integrate properly.
|
| But all of this is beside the point. Obviously you are not
| going to land open loop. You need sensors which tell you where
| you are and how fast you are going.
| grog454 wrote:
| > China's Three Gorges Dam slowed down the Earth's rotation by
| 0.06 microseconds per day [2]. That's actually not a big deal
| because the rotation has variance all of its own from tides,
| weather, etc
|
| I'm confused, how is the mean changing less impactful due to
| relatively high variance? If the was no variance at all, would
| .06us be a disaster?
| ordu wrote:
| It _may_ be a disaster, but if we manage to live with
| variance that are higher than 0.06 microseconds per day, we
| should manage this small change in an average.
| gonzo41 wrote:
| I think people forget how much US national effort was dedicated
| to the space race. These guy's did incredibly well, even with
| modern advances for the money they are working with.
| ghaff wrote:
| Yes. And with a little less luck/skill, the Apollo 11 lunar
| landing could have ended up as a disaster too.
| bell-cot wrote:
| A bit of backstory on just how far they went, to prepare for
| that mission-critical bit:
|
| https://en.wikipedia.org/wiki/Lunar_Landing_Research_Vehicle
|
| Note how willing they were to risk life and limb in training
| exercises, and Armstrong's comments on how important the
| skills gained there were to their actual mission success.
| bell-cot wrote:
| That...but also the generation which had (so to speak) stepped
| up and won WWII was running the show. Their skills at,
| experience with, and dedication to giga-scale technological
| development programs and bleeding-edge aerospace missions made
| an enormous difference.
| gonzo41 wrote:
| You're overestimating an older generation and underestimating
| the impact of what you can do with unlimited money, and 400K
| people working on one problem.
| bell-cot wrote:
| Perhaps. But ~unlimited money and ~unlimited people are the
| backstory for pretty much every massive government or
| corporate boondoggle, ever.
| prottog wrote:
| Agreed. The Apollo project was 2-3% of GDP at the time,
| compared to some modern projects:
|
| - Second Avenue Subway at a projected total cost across
| all phases of $17B vs. the GDP of NYC at $1T = 1.7%
|
| - Berlin Brandenburg Airport at a final cost of EUR7B vs.
| the GDP of the city of Berlin and the federal state of
| Brandenburg combined at EUR228B = 3%
|
| - California High Speed Rail at a current estimate of
| $128B for the full LA-SF system vs. the GDP of California
| at $3.6T = 3.5%
|
| And all of these examples understate the problem, since
| the GDP was lower when the projects began, the costs may
| continue to rise as the projects progress, and outside
| (national-level) funding assistance is also used. So
| there is at least some merit to the idea that we just
| can't build as well as we used to.
| mschuster91 wrote:
| > So there is at least some merit to the idea that we
| just can't build as well as we used to.
|
| We could, there is nothing preventing the US or Europe to
| return to 1970s taxation for companies and the filthy
| rich. The reason why we can't build like back then is to
| a very large part the erosion of the tax base to pay for
| it.
| prottog wrote:
| The data does not support your claim. US government
| expenditure as a fraction of the GDP was lower in the 70s
| (30-35%) than it is now (35-40%). The government revenue,
| about the same (around 30%). So the tax base is roughly
| the same relative to economic output, and spending
| slightly higher, with the difference made up for by
| deficits.
|
| The Transcontinental Railroad was built in the 1860s and
| the Hoover Dam in the 1930s, both when government
| expenditure as well as taxation at all levels were a
| single-digit percent of GDP. I suppose by your logic we
| would be a galaxy-faring species if only we were able to
| tax the likes of Bezos and Musk?
| [deleted]
| machina_ex_deus wrote:
| The Apollo moon landings were such an insane achievement. They
| did it in a time where digital processing was in it's infancy and
| barely existed, minimization technology was undeveloped, many
| modern materials which are much stronger and lighter weren't
| invented yet.
|
| And they managed to live broadcast from the moon! Storage was in
| it's infancy, so even storing a video from the moon was
| impossible (they would need many reels of film that just wouldn't
| fit.
|
| Digital cameras weren't invented, you only had analogue cameras.
| Most of them required film - and can't be developed on the spot,
| it requires special equipment. So to get video from the moon, the
| used cathode ray tube cameras - and even the cathode ray tubes of
| TV news were huge at the time, you can look at pictures, these
| things used to take a whole truck to carry. But they managed to
| get a very small cathode ray tube camera there, and to film long
| videos of hours of missions on the moon.
|
| And get managed to broadcast it all with analogue RF all the way
| from the moon to earth. With no digital signal processing,
| because that wasn't fast enough back then for any real time use.
| And with surprisingly low noise for an analogue transmission.
| They made a whole network of receivers on earth to be able to do
| it.
|
| Today all of that would be cheap, but back then it must've been
| quite the achievement.
|
| They also had pretty minimal computational power available
| compared to newer attempts. But maybe putting a human in control
| is enough.
|
| Google's moon challenge is pretty cool. They actually wanted to
| give a bonus for taking pictures of the original moon landing
| site. That could've been really nice.
|
| But sadly, NASA was afraid that the site would be disturbed and
| declared no fight zone over it.
| mulmen wrote:
| > But sadly, NASA was afraid that the site would be disturbed
| and declared no fight zone over it.
|
| Seems like a reasonable precaution for a industry that brought
| us "move fast and break things" and normalized endless bugs as
| an unavoidable natural law.
| MarcoZavala wrote:
| [dead]
| nirmel wrote:
| Am I the only one who thinks the US didn't actually achieve
| this achievement, which indeed would have been "insane" if they
| had? See: https://www.youtube.com/watch?v=DxW__ZtZApo Of course
| they faked it. It's too damn hard, and they weren't about to
| risk the lives of astronauts.
| nikanj wrote:
| The uploader has not made that video available in my country.
| I wonder if they're worried about stricter libel laws
| michaelmrose wrote:
| You should consider spending less time on youtube viewing
| conspiracy theories or at least don't bring them here. Apollo
| 11 left a reflector on the moon that we have used since to
| accurately measure the distance between the Earth and moon
| since. A good rule of thumb to avoid promoting poorly sourced
| material is to never use a youtube video to "prove" anything
| that doesn't have a more legitimate primary source.
| simonh wrote:
| You're not the only one, but there don't seem to be many of
| you. There's just way too much evidence it was a real space
| program and all the counter arguments are weak, flawed or
| straight up based on absurd misunderstandings and
| misinterpretation of the evidence.
|
| Even aside from the evidence itself it fails the massive
| conspiracy with no leaks test. Conspiracies leak
| exponentially with the number of people in the know. SOE
| worked this all out running operations in occupied Europe.
| This is why top secret intelligence operations employ
| incredibly rigorous procedures. Let's say you have a spy in a
| foreign country, you make sure only a tiny number of people
| know the details, preferably low single digits, you layer and
| compartmentalise everything, you run decoy operations. Even
| then it's incredibly hard, the vast majority of operations
| eventually leak. Only very few of the best run operations
| with very few people in the know ever last.
|
| With the moon landings many hundreds, more like thousands of
| people would have to know. All of the astronauts and their
| backups, the model and set makers, the film crews, the
| mission flight staff, the film and video technical production
| staff. There were six manned landings, they'd have had to do
| the whole faking thing over and over again for years. Plus
| these people wouldn't be trained spies, they'd be mostly
| civilians with very specific technical skills so you can't be
| picky about who you select for it.
|
| There is no way this wouldn't have leaked. Somebody on the
| inside would have talked, especially by now with the Cold War
| well and truly over. Why wouldn't they? But no, nothing, not
| even a hint after fifty years.
| dev_tty01 wrote:
| Yes, you are the only one.
| bouncycastle wrote:
| back on those days, the best brains of their generation were
| not occupied with thinking about how to make people click
| ads...
| spaceman_2020 wrote:
| I suspect part of the moon landing failure has to do with the
| primacy of physics in our technology in that era compared to
| electronics today.
| sidlls wrote:
| The best brains of this generation aren't focused on ad
| clicks, either.
| izacus wrote:
| No, they were thinking about how to effectively kill as much
| people as possible at a distance.
|
| Remember that apollo program (just like soviet one) was an
| offshoot of military wanting to erase a nation on the other
| side of the world with efficiency.
| prepend wrote:
| Interestingly I bet the kill thinkers killed fewer than the
| ad thinkers. Ads make people buy more stuff. More stuff
| makes people fat and unhealthy and sad and increase the
| mortality rate.
| izacus wrote:
| That is some world class cope there.
| trothamel wrote:
| That's not actually true.
|
| The Mercury and Gemini programs, sure - both of them used
| ICBM as their boosters. So did the Vostok, Vokshod, and
| Soyuz programs.
|
| Apollo was very different. The Saturn booster is so much
| larger and more complicated than any reasonable ICBM would
| be, it would be gloriously inefficient at that role.
|
| The Apollo program was a cold war thing. But it wasn't a
| military thing, it was a different kind of competition.
|
| If you take a look at the vintage Rockets of the World
| poster (https://venngage-wordpress-
| gallery.s3.amazonaws.com/uploads/...) you can see how much
| bigger the N1 and Saturn V (spanning the last two rows),
| compared to the earlier boosters on the third and fourth
| rows.
| izacus wrote:
| Apollo was absolutely a part of a military thing (as I
| said, an offshoot) as well and it's also a reason why it
| died before finishing when its military use became
| questionable.
| jfoutz wrote:
| Well, from that perspective, what isn't a military thing?
|
| The internet is a communication to survive nuclear war.
| Forklifts and pallets were to simplify military
| logistics. The highway system is to provide point to
| point connections without risking losing a railway. Cell
| phones are kinda private, but a lot of the components
| came from special hardware for the military.
|
| I'm sure there's lots of neat tech we use everyday that
| isn't rooted in military funding, I just can't think of
| any at the moment.
| rwmj wrote:
| Not really. By the time Apollo came around, erasing the
| nation on the other side of the world was pretty much a
| solved problem. 400,000 people were employed on Apollo and
| they weren't military (well, a few were) and were not
| thinking about nuclear weapons.
| izacus wrote:
| Even Space Shuttle later was driven (and funded) heavily
| by military applications, a lot of Apollo funding came
| from wish of improving missile guidance systems as well.
|
| You're trying to make a distinction where there is none -
| it's the same bag of money. Which also why the money
| quickly dried up when rocket guidance, indeed, became a
| solved problem. Before Apollo was finished.
| rbanffy wrote:
| > they were thinking about how to effectively kill as much
| people as possible at a distance.
|
| And rockets that can navigate precisely are a nice side-
| effect of that.
| LadyCailin wrote:
| No, they were in gay conversion therapy, or having to walk 3
| miles just to use the only colored restroom on the campus.
| George83728 wrote:
| [dead]
| CatWChainsaw wrote:
| That sounds like a race to Instagram-ify the moon. Nothing sad
| about preventing that.
| throwaway6734 wrote:
| IIRC the landing would have been a failure too without Neil
| Armstrong's skill as a pilot under pressure
| actionfromafar wrote:
| The video feed was HD video too! Alas, only one room in
| Australia got to see the HD video feed.
| pulvinar wrote:
| Folks, NASA's Surveyor program (1966-68) is a better comparison
| here, not Apollo. It made the first moon landing by the US
| (after the Russian's Luna 9, 4 months before), and the first
| landing of the series was successful, though some of the others
| failed. It was a fully automatic landing, unlike Neil
| Armstrong's.
|
| It built on lessons learned from the many failures of the
| Ranger program before it. And the Russians lost 12 landers
| before their first success.
| croutonwagon wrote:
| Its important to note that the Moons gravity (and other
| bodies) isnt a static thing. There are places were its more
| apparent and places where its less.
|
| In fact we dont even know of the Apollo 11 LM is still in
| orbit of the moon or not.
|
| https://www.youtube.com/watch?v=dBHbLV7xEhc
|
| Scott Manley's video also has some links in its description
| for some of the tools NASA uses for more precise
| gravitational estimations and whatnot. Its pretty cool.
| nanumbat wrote:
| My late father-in-law was a manager at Hughes working on
| Surveyor 1. My wife shared his (unpublished) notes and audio
| recordings of the the project with me. It was an absolutely
| remarkable achievement. I can confirm that the Hughes team
| was devastated that Luna 9 got there first, however they
| actually learned quite a bit from the Luna 9 video feed.
|
| It should also be noted that Luna 9 was a relatively hard
| landing, not suitable for a crewed spacecraft. Surveyor 1 was
| the first soft landing, and a prototype for the missions that
| would follow.
| williamDafoe wrote:
| Apollo 11 was set to land automatically using the computer
| when Armstrong took controls at the last minute supposedly to
| avoid a Boulder Field. It's not really clear that his
| takeover of the automatic controls was necessary - what is
| clear is that mankind landing for the first time on another
| celestial body using automatic computers is probably not
| cool. ... And NASA was driven and sold to the public as a
| human interest project ...
| djmips wrote:
| Nevertheless he didn't takeover completely - it was still a
| computer assisted landing.
| scrapcode wrote:
| > But sadly, NASA was afraid that the site would be disturbed
| and declared no fight [flight?] zone over it.
|
| Moon landing deniers would eat that one up.
| Maursault wrote:
| Most don't make the distinction, but that the Apollo missions
| succeeded in landing on the Moon is far less doubted as
| whether the footage was faked.[1]
|
| [1] https://www.imdb.com/title/tt2085910/
| api wrote:
| I'm surprised how many people still believe this in spite of
| photos having been taken of the sites from Lunar orbit by
| other space programs.
|
| It seems to be an article of faith for some though. We could
| have a space tourism industry with a package to visit the
| Apollo landing site museum on the Moon and a ton of people
| still would not believe.
| hinkley wrote:
| There are retroreflectors on the moon you can use to prove
| we were there.
| funnymony wrote:
| For such proof to be effective, one has to trust lot of
| formulas from physics books. (Source of flat-earthery is
| extreme distrust in everything that is not a first-hand
| experience. You can't prove much if your limited
| exclusively to first hand experience)
| MarcoZavala wrote:
| [dead]
| klntsky wrote:
| Does the existence of some object on the moon surface prove
| that the broadcast was live and that the spaceship
| successfully returned?
| shrimp_emoji wrote:
| No, but your probability heuristic is catastrophically
| flawed if, from that, you conclude the landing was faked
| despite material having been placed up there.
| api wrote:
| The presence of the expected artifacts such as the LEM
| descent stage, rovers, foot and rover tracks, and science
| packages all left just where the mission logs said they
| would be are certainly pretty suggestive.
|
| The alternate explanation would be a hoax so elaborate it
| involved robotic missions to leave props on the moon on
| top of a giant disposable rocket launch, satellites to
| fake the signals, and a huge cutting edge filming effort
| to fake the broadcasts. At some point it starts to get as
| hard as just going to the damn moon.
| mjevans wrote:
| I believe in the evidence that the moon landings
| happened.
|
| However, as you suggest, even if that evidence were faked
| to such an elaborate degree could be an even higher
| technical feat that would be worthy of even greater
| recognition.
| CrampusDestrus wrote:
| This was a commercial vector, not some experimental top US
| priority stuff.
|
| It's unfortunate that aboard the commercial craft there was
| stuff from national space programs, but this was not comparable
| to NASA's mission. It's just like SpaceX exploding a ton of
| rockets to further their research instead of obsessing over
| getting everything perfect on first try. Unfortunately they
| should have done more mock missions, but there wouldn't have
| been enough funding I fear
| [deleted]
| machina_ex_deus wrote:
| Even if you knew back in 1970s the exact specification of
| iPhone camera, you still couldn't manufacture it because
| improvement in manufacturing is a gradual self dependent
| process where the new equipment is built by the old
| equipment, and you can't make sudden jumps in accuracy or
| minimization because these things depend on weaker versions
| of themselves.
| prottog wrote:
| You might have a point about the semiconductors involved
| (that back in the 70s the engineering ability just wasn't
| there), but as a counterpoint, almost anything can be
| manufactured given an unlimited budget, like the moon
| landing programs had. We even turned lead (well, bismuth)
| into gold back in the 80s.
|
| Making one of something where the cost is no object is
| almost always possible. Making millions at a commercially-
| viable cost is much more challenging.
| soneil wrote:
| I always find the "unlimited budget" angle interesting.
|
| The entire Apollo program had a budget of $165.5 billion
| (in 2021 dollars), over a 10 year program. $16.5 billion
| per year. It's a big number, but it's absolutely dwarfed
| by things like a $600bn military.
| dragonwriter wrote:
| > The entire Apollo program had a budget of $165.5
| billion (in 2021 dollars), over a 10 year program. $16.5
| billion per year. It's a big number, but it's absolutely
| dwarfed by things like a $600bn military.
|
| Apollo was actually pretty close to the same GDP share
| (2.5% of GDP annually) as the modern defense budget (3.1%
| of GDP).
|
| Inflation-adjusted numbers ignore that we have more
| people _and_ more value produced per capita now than in
| the 1960s.
| LadyCailin wrote:
| Related: the term "The Adjacent Possible". I first heard it
| here: https://www.pushkin.fm/podcasts/cautionary-tales/the-
| false-d...
| fn-mote wrote:
| As a counterpoint: NASA has an _extremely_ careful process
| and their success rate is high. It's expensive, though, and
| you have to develop an engineering process that supports
| it.
|
| When you're sending a probe to Mars, the trial runs are
| very expensive. They spend a lot of time making sure that
| the mission will be successful. I'm skeptical that anywhere
| near the same level of care is going into the private
| missions, but I the reason is cost, not that they can't
| bootstrap themselves up with Earth-environment
| experimentation.
|
| Yes, I'm aware at least one of the Mars probe missions
| totally failed. I don't think that detracts from the
| overall point. They weren't screwing up a bunch of missions
| before they got one right.
| WalterBright wrote:
| It appears that the money spent to ensure a one-off
| success is far more than the sum of all the costs of the
| failures of SpaceX.
| eternalban wrote:
| 6 landing attempts, _all_ successful, late 60s technology:
| mission launch land days since last
| successful landing ---------------------------------------
| ------------------------------ Apollo 11 July 16, 1969
| July 20, 1969 - Apollo 12 November 14, 1969
| November 24, 1969 126 Apollo 14 January 31, 1971
| February 9, 1971 431 Apollo 15 July 26, 1971
| August 7, 1971 272 Apollo 16 April 16, 1972
| April 27, 1972 347 Apollo 17 December 7, 1972
| December 19, 1972 316
| propogandist wrote:
| has any of the recent attempts to the moon given us footage of
| the lunar lander and other machinery that was left behind from
| the prior missions?
|
| this would easily put the conspiracy theories to bed
| infradig wrote:
| Yes
| hgsgm wrote:
| And No to the second question.
| mensetmanusman wrote:
| You can see the stuff left behind from earth, especially the
| retro reflectors.
| st_goliath wrote:
| > has any of the recent attempts to the moon given us footage
| of the lunar lander and other machinery that was left behind
| from the prior missions?
|
| Yes, e.g. LRO launched in 2009
| (https://en.wikipedia.org/wiki/Lunar_Reconnaissance_Orbiter)
|
| > this would easily put the conspiracy theories to bed
|
| no, you are dealing with people who nit pick data, rejecting
| anything that does not support their position as falsified.
|
| Attempts at reasoning are in my experience often met with
| emotion and ad hominem responses (e.g. the classic comparison
| to species of Ovis). Logic does not apply here.
| freddie_mercury wrote:
| The Lunar Reconnaissance Orbiter from 2009 sent back
| pictures, yes.
|
| It clearly didn't put the conspiracy theories to bed.
| dgrin91 wrote:
| All with a much bigger budget & many more people working on it.
|
| Oh and it wasn't all success. Apollo 13 was a near miss. Apollo
| 1 had fatalities. Several other apollo missions has near
| misses. It was a very high risk operation.
| joshuahedlund wrote:
| Yeah but 1) that ignores the failed unmanned attempts that came
| before these, 2) these were all manned. I could see it being
| "easier" to land when you are manually adjusting your descent
| than when you are entirely relying on sensors and preprogrammed
| behavior. (Apollo 11 literally would have crashed if Armstrong
| hadn't veered off course to find a smoother landing site)
| elteto wrote:
| Those were supported by a 400k people workforce, a basically
| unlimited budget, and the political and moral support of the
| most powerful nation on Earth.
|
| I'm not trying to discount Apollo here, I myself can barely
| comprehend their achievement at their time. But the magnitude
| of the effort was much much larger than this one mission.
|
| And let's not forget Grissom, White and Chaffee. NASA was _not_
| on a successful path pre Apollo 1, as shown by the post-
| disaster analysis reports. Speculating here, but most likely we
| would not have gone to the Moon had Apollo 1 not happened.
|
| Space is _incredibly_ hard.
| Silverback_VII wrote:
| the big elephant in the room.
| eternalban wrote:
| .
| Dah00n wrote:
| Which? Apollo 13?
| messe wrote:
| It seems a bit disingenuous to omit Apollo 13, which failed on
| the way to the moon. The fact that it failed well before the
| landing attempt, speaks to the difficulty of even getting to
| the point where you can consider a landing.
| eternalban wrote:
| That's your opinion. I don't consider it "disingenuous",
| rather focusing on the act of getting a manned lander from
| orbit down to the surface of the moon. 6 tries, 6 successes.
| messe wrote:
| That's completely fair, it's definitely just opinion as to
| what to include. Getting to lunar orbit can reasonably be
| considered a separate challenge to landing, so it might
| make sense to separate them.
|
| In that case though, I think Apollo 10 should at least be
| mentioned in some capacity, as it was a dress rehearsal
| that came within 16km of the lunar surface, and tested much
| of the lander's systems. Not listed as a failure or
| success, just mentioned, as it's a very relevant test.
| emmelaich wrote:
| Hardly saying it's easy but ...
|
| > _What makes landing on the Moon so difficult is the number of
| variables to consider_
|
| Compared to Earth, surely it's easier. Less terrain difference,
| lower gravity. It's getting there and the remoteness is what
| makes it hard.
| Delk wrote:
| On the other hand, there's no atmosphere on the Moon to speak
| of, so you actually have to slow down using propulsion against
| the gravity for a soft landing. Heat from the atmospheric entry
| when getting back to the Earth is certainly a concern but the
| atmosphere also takes care of the vast majority of slowing the
| descent (or ~all of it, if you count the use of parachutes at
| the end).
| TeMPOraL wrote:
| Earth gives you a stupidly wide margin of error, where the Moon
| gives you none (and Mars very little) - because of its dense
| atmosphere. Landing on a world with an atmosphere means there
| is a passive force that tries to get you stop (relative to the
| surrounding medium). So, as long as you survive the hell of
| reentry, you can help yourself with lifting surfaces and
| parachutes. In contrast, on the Moon, you have to zero out your
| velocity at exactly the right moment. Do it too late? Crash. Do
| it too early? Crash. Run out of fuel just a little bit too
| fast? Crash.
| rbanffy wrote:
| > you have to zero out your velocity at exactly the right
| moment.
|
| Not quite. You can compensate with a landing gear that can
| survive your terminal speed going to zero very quickly and
| absorb the extra energy.
|
| The math is much simpler on the Moon because there is no
| atmosphere.
| bitL wrote:
| Dumb laser distance measurement should solve that easily for
| you. You can literally use some very basic math with thruster
| output based on your downward distance/speed.
| dexwiz wrote:
| What if you kick up a bunch of dust?
| bitL wrote:
| That would be very near the surface and with 10x lower
| gravity one could afford some error.
| TeMPOraL wrote:
| With 1/10 gravity dust also goes quite a lot higher.
| That's on top of lack of atmosphere letting dust float
| higher. Not to mention, there's going to be a lot more
| dust to kick up.
|
| Anyway, the easiest way to get a feel for these things is
| to play some Kerbal Space Program. Try doing some moon
| flights. You'll quickly realize that the part of the
| mission that feels easiest on the home planet (landing)
| also feels the hardest on atmosphere-less bodies, and
| vice versa (e.g. taking off, or slowing for landing).
| TeMPOraL wrote:
| Sure. The problem is delta-v. If you zero out too late, you
| crash, but if you zero our too soon, you'll likely run out
| of fuel and either crash or won't be able to take off or
| otherwise complete the full mission.
|
| Managing delta-v is half of what makes a Moon landing
| require precision. An atmosphere can let you ignore this
| half to a degree (depending on specifics of
| vehicle/mission).
| hgsgm wrote:
| But you need to calibrate that to extremely high tolerance.
| That's harder than not needing to care at all.
| fooker wrote:
| It's not that simple.
|
| What happens when you over-compensate with the thruster?
|
| Sometimes you can recover from that, sometimes not.
| hgsgm wrote:
| People go to the moon for the food not the atmosphere. ;-)
| ithkuil wrote:
| Bring your own atmosphere!
| kwhitefoot wrote:
| Time to watch A Grand Day Out with Wallace and Gromit
| again!
| kryptiskt wrote:
| Earth is pretty easy to do if you do it the simplest way, via
| atmospheric braking all the way down. You have to have a heat
| shield and parachutes, but if you have the equipment the
| atmospheric braking doesn't require any fancy calculations
| besides getting the entrance angle right (so you don't bounce
| off into space or burn up by going too steep).
|
| Mars is probably the worst of both worlds, you have a thin
| atmosphere that is a nuisance but not very good for braking.
| [deleted]
| AbsoluteCabbage wrote:
| [flagged]
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