It's worth pointing out that this is the first extremely public, widely acknowledged high risk mission NASA has done in over 50 years. The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle.
According to NASA's OIG, Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle. There genuinely is a world where they don't make it back home.
I am grateful that they did. And I'm grateful that we're going to go even further. I can't wait to see what Jared's cooking up (for those who don't know, he made his own version of the Gemini program in Polaris and funded it out of pocket).
This seems insane to me. That X decades later we accept, with all our advancements in tech, a weaker system than ever before. That if we send 30 people we _accept_ that one is possible to die.
That's the starting point? That's what we document as acceptable?
But if I'm allowed to repeat myself from elsewhere in the thread and the meat of the above thing,
It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved. Even with the Commercial Cargo and Crew Program (C3P), NASA has set the acceptable mortality threshold at 1 in 270 over the entire mission and 1 in 1000 on ascent / descent. If they could set it higher by gaming the math, they would. They can't.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive, as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
I am stunned to see that LoC risk assessment.
I kept wondering to myself over the past week, “will this be the last USA-supported human space travel if these astronauts don’t survive?”
I’d have a hard time imagining the general public would support any future missions if they hadn’t survived.
These astronauts are some elite humans. My respect for them is even greater now that I’ve seen the risk quantified.
Adding to it - Apollo 13 was a mission where 3 men should have died, but somehow didn't. If it had happened while the LM was on the moon, you would have had the CSM lose power, and then two men on the moon would have had no way to return home.
(And for the shuttle design mission - my understanding is it was likely the ability to do a HEXAGON-style film return mission in a single orbit, before the Soviets knew what was happeneing.)
note - I can't verify any of the following, it's more - for lack of a better term - aerospace nerd fan theory at this point.
Post-collapse, people think that the Buran justification was paranoia. But based on what I've read / seen (though this is getting hard to source, so I might be just good ol' hallucinating here), they weren't entirely wrong. The subtext around that large payload bay had to do with the Soviet pursuit of systems like Fractional Orbital Bombardment System (FOBS) https://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment... that weaponized space.
Again, there's a reason for those ASAT tests. There's a reason for the weird specifications set in the early 1970s for the Shuttle. And I don't think deploying a spy satellite alone is it. But this is speculation. AFAICT, nothing was put on paper.
It would have been an incendiary WW3 starting act to capture a Soviet asset. But I think it is understandable if certain people within the American blob wanted that capability at hand.
I wish I was immortal. I'd drop everything for a decade and try to find people from the time who're still alive (and some still are!) and ask them these questions directly - on the record – for posterity's sake. I suspect, we came much closer to war via space than most people think. And because we didn't, we'll eventually repeat these mistakes.
---
Oh and then there was the documented attempt to capture Salyut-7 https://www.thespacereview.com/article/2554/1
Somehow all the numbers just happened to line right up. :)
Read Payne Harrison's 1989 novel Storming Intrepid, followed by NASA publication SP-4221, "The Space Shuttle Decision," from 1999. [1] The first is a pretty good depiction of what you're imagining, and the second explains why the imagination of a technothriller author is where that idea went to die. Then maybe give your head a shake. If Reagan had violated the Outer Space Treaty - via NASA of all agencies! - how do you imagine it'd have stayed secret over these forty years just past?
[1] https://web.archive.org/web/20241229052235/https://ntrs.nasa...
Obviously I realise the shuttle program was pretty far away from being able to head out to the Earth-Sun L2(AB, and wasn't even working towards it. But man, it would be nice to have that ability.
> There’s a reason why there wasn’t an Apollo 18, or 19 and 20. Even though funding had been secured, an executive decision was made to kill the program early, because LoC was inevitable.
Was funding really secure? I believe that was the main sticking point; a quick search [0] seems to confirm this, and the John Young quote below backs it up: "Even if they’d had the money..." Not to say the risk wasn't a factor too of course, but it doesn't look like funding was otherwise guaranteed.
Anyway, I think what sets the risk of the Shuttle apart from Apollo is summed up nicely in one of the quotes (in reference to the Apollo program): "The awareness of risk led to intense focus on reducing risk." In the Apollo program, there was a pattern of rigorously hunting down and eliminating any possible known risks, leaving unknowns as the primary source of risk; on the other hand, the Shuttle program let known risks accumulate continuously until crews paid the price for a bad draw.
When debris hit Atlantis on STS-27 [1] and the shuttle only survived on a one in a million stroke of luck -- the completely broken tile happened to be over an aluminum mounting plate -- it should have been taken as a free lesson on one more known source of risk to eliminate. Instead, it led to seven people dying completely preventable and unnecessary deaths a few years later.
Spaceflight is inherently risky, it's true. That's why things like the Orion heat shield are so worrisome; because it is physically possible at our current level of technology to make it safer, and yet for political / funding / etc. reasons we're not doing the best we can.
[0] https://airandspace.si.edu/stories/editorial/why-did-we-stop...
The ejection seats on Gemini were a joke, and there's an anecdote Gene Kranz tells in his book about Gemini 9 where he thought it was too risky for them to cut away the shroud on the thing they were going to dock with (the Agena having blown up on launch) but NASA was this close to overriding him and doing it anyway (they were saved by the astronauts vetoing it, which was good because the EVA, separately, that Gene Cernan did was incredibly harrowing. he was sweating, way overworked, could barely see)
[wiki link](https://en.wikipedia.org/wiki/List_of_spaceflight-related_ac...).-,During%20spaceflight,fatality%20rate%20at%202.4%20percent.)
Note that all the fatalities have been launch or landing related, not in space itself. Clawing out of this gravity well is tough. Make Earth a bit larger and you’d never get off it without something like NERVA or nuclear pulse Orion.
I wonder sometimes if that’s another thing to toss in the Fermi paradox bucket. Many rocky planets might be much more massive than Earth. On one with 3X our gravity a space program might never get going.
(Some would snidely say as long as they don't put seven people on the rocket they'll be fine.)
Apollo 13 was a very close call. If that had ended in failure the mortality rate would have been 1 in 6.
So 1 in 30 would be a pretty clear improvement from Apollo, and we are a lot better and more thorough at modeling those risks and testing systems than we were during the Apollo program.
I’d say we’re doing better!
how do you keep past performance while stop performing it for XY decades?
I waited until splashdown to permit my emotions to get involved, and I'm glad I did. It was really something earlier, to hear my whole neighborhood bar set up a cheer for an American mission to the Moon.
I think you're being a pedant, if your point is a grazing entry causing rebound skip ultimately returns to some orbital path downward.
They certainly could've gotten the return wrong but with a perigee of 119 miles they arent even in a stable orbit and likely could deorbit themselves using only rcs thrusters at apogee, or by just waiting a few orbits.
In fact, the trajectory they chose for this mission exploited the opposite effect to yield a free return without propellant expense.
In the modern day, the chance of a math error being the root cause behind this failure mode are vanishingly small, but minor burn execution mistakes that do not require hundreds of extra pounds of propellant are definitely plausible. They were extremely common in the early days of spaceflight and plagued most of the very first moon exploration attempts. Again, with modern RCS this is unlikely. But reentry is still incredibly tight and dangerous. Apollo famously had a +-1° safe entry corridor, and Orion is way heavier and coming in even faster. If their perigee was off they could’ve easily burned up or doubled their mission time, which they may not have been able to survive.
Artemis II never escaped Earth’s pull.
That video that NASA put out where the craft did a sling shop around the moon is extremely deceptive. The pull of the moon had very little effect.
If they had missed, they would have eventually crashed back to earth in the worst case, and best case just re-adjusted and returned a little bummed.
We're a very primitive species, and the forces involved here are genuinely new. And no, Apollo wasn't much better either, at least 10 astronauts were killed in training or burned alive (8 NASA, 2 sister MIL programs), as well as (far worse, because astronauts sign up for the risk) one member of ground staff.
People love to hate the Shuttle, and it ended up being subpar / fail expectations due to the political constraints NASA was under, but the Shuttle was a genuine advance for its time – a nonsensical, economically insane advance, but still an advance. If you look at the Shuttle alternative proposals / initial proposals as well as stuff like Dynasoar and Star Raker, you'll see NASA iterating through Starship style ideas. But those were rejected due to higher up front capital investment at the time.
The Shuttle is an odd franken-turduckling, because it was designed for one mission and one mission only. And that mission never happened. That cargo bay existed to capture certain Soviet assets and deploy + task certain American space assets and then bring them back to Earth.
And that's the bit that's hard to emphasize. The fact that the Shuttle could put a satellite up there, watch it fail, then go back up, grab it, bring it back, repair it, then launch again was an insane capability.
Was the program a giant fuck up at the end? Yes. But does that mean Artemis will be safer than the Shuttle? No. That's not how the energetics, time from civilization, acceptable risk profiles etc. work out.
Shameless plug, wrote a bit about the Apollo hagiography, Artemis and risk here – https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri...
As with any aerospace mishap, it's a chain of events, not just one cause.
Unless you happen to have some deep links into NASA, in which case please elucidate us all, then why not celebrate a happy and safe return from a sodding dangerous mission that involved things like >25,000 mph relative velocity and some remarkable navigation.
When you depart earth (close quarters gravity, air resistance, things in the way), everything moves really fast, really fast and any acceleration becomes an issue really ... fast!
The moon moves, the earth moves: both famously in some sort of weird dance around each other and both orbit around the sun. Obviously the moon affects the earth way less than vice versa but it still complicates things.
I think that NASA did a remarkable job of making Artemis II look almost routine and I don't think that was down to behaving as they did in the past.
I have been excited for Artemis--yes it's big and expensive and late, but look how it has brought out the best of what humans can be--but, despite all that, the heat shield situation was textbook "normalization of deviance." Just as the O-rings were not designed to have any damage but they retroactively justified it was okay, just as there was not supposed to be any foam or tile damage but they retroactively justified it was okay, so too was the Artemis I heat shield not supposed to come back with damage, but they...
I'm not trying to be negative, and risks are inevitable, but the resemblance to me was uncanny. The lesson with normalization of deviance is that a successful result does not inherently mean a safe decision. After all, most of the time that you play Russian Roulette you will escape unharmed.
The heat shield failure was a test and the result was a working heat shield, when it counted. That's the point of tests. NASA already had several working heat shields from the old missions but the new one needed testing - for the shape of the craft etc. They already had a lot of data from the old efforts (that worked).
I think that exit and re-entry are almost routine now, provided your rocket doesn't explode. The tricky bit is out there in space and trying to make the moon a resource of some sort.
The mere fact that the outcome was successful does not inherently indicate that the decision-making was safe: the O-rings "worked" for 24 missions and the foam/tiles "worked" for 111. Nevertheless there were ample warnings and close calls.
Reentry from the Moon is not routine. Re-entry speed was about 40% faster than from low earth orbit, and kinetic energy goes up by the square, so about double.
Probably the rose tinted glasses of being a child but being from Florida I always had a sense of amazement and wonder as I heard the sonic boom of the shuttle returning to earth.
Really felt like I was coexisting in this incredible scientific powerhouse of a country full of bright and enabled peoples that knew how to prioritize curiosity and innovation.
Feeling like a bit of a "vibe" post which is everything wrong lately but I can't help but feel some satisfaction that we're still able to accomplish something like this in our space endeavors.
I definitely don’t envy kids that are born nowadays.
Not to say it's the best of times, nor to say it's the worst of times, mind you. Just that it's really hard to objectively compare.
It all boils down to equations that describe the world accurately, and a way of experimentation, iteration, thinking that gets us all the way to do something this unbelievably complex.
I like starting from the fact that Ptolemy was able to get the accuracy of the "motions of the heavens" down so well that it took more than a thousand years to get observations that showed discrepancies. The math, it maths.
All of these factors and more have to be taken into account if you want your predictions to be accurate. Aside from telemetry processing, most of the computing power on the ground during a space mission is used for churning out navigation solutions.
Fun info: The NASA orbital codes include things like photon pressure... from sunlight reflected off of other planets in the solar system. At some point, I think they are just showing off :)
Bring on Artemis III and IV!
Note: next time, pack a walkie talkie. ;-)
The commentary said that the initial problems with the boats approaching Integrity was due to an unexpected swell. Unexpected, in the Pacific?
Edit: all of the Apollo missions, except 8, had their stabilization collars inflated in under 20 minutes. With Integrity today it took nearly an hour more.
Bravo, Artemis team for an exceptional return to extra-orbital space travel.
Also Orion and other capsules fall like a rock (steep reentry profile ) compared to shuttle/starship, which intentionally slow down the reentry and kinda glide (ballpark 10min with capsules compared to 30min with shuttle/starship).
tl;dr: capsules get fully enveloped in plasma due to their shape, size and reentry profile
The reason the heat shield failed was due to gas buildup inside the ablative material. This was due to the skip reentry profile they used, where the craft does a single skip (as in skipping stones) during reentry. The high bounce caused the shield to be heated enough that the heat penetrated the material causing gas release but not enough that the material ablated. Thus gas would build up deep inside up until it caused large chunks to break off. They could reproduce this in tests.
The fix was two-fold. First they lowered the bounce height, so a much less pronounced skip, avoiding the lowered heating of the shield. And they tweaked the material formula a bit so it was more porous, allowing subsurface gas to escape rather than build up.
For reference the shuttle generally reentered at ~17.5K mph, and today's was 24K-25K mph.
It's not clear that we could build a craft with wings that could survive that. So then you're looking at adding fuel just to slow down, plus fuel for the weight of the wings themselves, plus fuel to carry all this extra fuel to the right place, etc.
Splashdown-style landings are the simplest and safest, parachutes are always good but adding water makes for another layer of safety (and of risk, to be fair, it could sink).
Space Planes are not only much more dangerous, but are not ideal for this type of mission. They carry a lot of extra weight (wings) that would affect how much fuel is needed to launch them to the Moon.
Capsules are safer and more lean in terms of weight.
The Shuttle was not ideal in many ways. It was used so long not because it was the best option, but because Congress wanted it to keep it going for jobs.
A small Apollo-style capsule that parachutes into the ocean has a simpler mission profile, which allows for simpler technical and operational requirements, which in turn reduces program cost.
They actually covered this in the broadcast: Helicopters are faster to get the astronauts to medical, smoother in rough seas, and there's less risk of being swamped by a rogue wave. Plus, since the astronauts might have fatigue/muscle atrophy/whatever, it complicates potential boat transfers.
From the broadcast, they made it sound like a big factor is the 2 hour program requirement to get the crew out of the capsule. Maybe they can't reliably hit that mark with a well deck recovery?
[1] https://www3.nasa.gov/sites/default/files/files/orion-recove...
That's a snappy one-liner but it doesn't address the real concerns.
First of all, subsonic lift is well understood and has been for decades. The answer is much more mundane: The Artemis mission profile does not require payload doors that open, no Canadarm, no requirement to service, launch, and/or capture satellites in orbit, and so like good engineers they designed the minimum vehicle that satisfies the requirements.
Also, the Shuttle was actually much more expensive to reuse than originally predicted.
I said easy. Not well understood. I can fly planes. It’s hard, and has limited room for fucking up. (It’s also hyperbole to suggest we understand lift. We don’t.)
Piloting a boat is easier and more forgiving. Hence, splashdown. You don’t need direction. You don’t need lift. Parachute physics is a backbreaker, but it’s symmetrical. Same for splash.
At no point were the astronauts piloting a boat. The reasons they splash down into the ocean has nothing to do with buoyancy being easier to solve, and even less to do with the ease of piloting a boat.
>It’s also hyperbole to suggest we understand lift. We don’t.
Maybe you personally do not understand lift, but "we" do in fact understand it. Please educate yourself before continuing this discussion any further.
control: "i guess we'll have to go back".
(paraphrased from memory)
I think that audio stream was designed to be POTUS safe.
It's becoming a public hazard, we must act!
It's especially tragic with younger people who seem to have no experience with handling genuine sincerity. They laugh nervously at it, as if they're unfamiliar with how to handle someone saying what they actually think and feel.
OP: "I'm happy they didn't die."
Response: "You're going to be less happy when they turn into the Fantastic Four and Dr. Doom shows up."
I'd refuse the mission just to avoid that meeting.
Missaved their version 2 Excel spreadsheet using the wrong file name causing confusion about this version was the latest.
Nearly missed a cell in their burn sheet had multiple lines of text until mission control reminded them to resize the cell.
Also, what were these puffs on thermal camera after the main chutes were deployed?
Heating likely plays a role as well.
I am not a rocket engineer, but I have read How Apollo Flew to the Moon and Ignition!: an informal history of liquid rocket propellants, both of which cover these issues. Highly recommended.
Apollo was, IMO, not successful at changing the course of human history. A really cool footnote, sure, but everything else that was to follow, nope, just a bunch of neat, interesting but ultimately meh science missions.
An exciting change would be more like Delta-V/Critical Mass, but NASA is not going to deliver that, at least not in any form it has taken thus far.
Because we stopped, we get to do everything over again with hardware from this century.
Imagine if your employer wanted to start using a software system it retired in 1972. What would you do?