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Artemis II safely splashes down

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Re: Artemis II safely splashes down

#211
post #171

Earlier quoted context omitted.

Astronauts are, as a group, extremely risk loving. Every single person who signs up to go into space knows what they’re signing up for - they’ve spent their entire life working for the opportunity to be put in a tin can and shot into orbit atop a million pounds of explosives. There’s a very valid critique that NASA has become far too risk averse - we owe it to the astronauts to give them the best possible chance to c…

My father, who flew combat missions for the Navy in Vietnam and then became a test pilot, told me after the loss of Columbia that if he had had a chance to make that flight and spend 7 days in Earth orbit, even knowing that he'd burn up on reentry, he'd have done it.

Your father is a better man than I am.

Re: Artemis II safely splashes down

#212
post #147

Earlier quoted context omitted.

It is about trends and perceptions - 70s were very hopeful, now with global problems - wars, climate, AI, uncertainty, what is growing is desperation. I definitely don’t envy kids that are born nowadays.

The '70s were not hopeful. Economy was terrible, Vietnam ended but still hung over the culture, Watergate, Three Mile Island, Iranian hostage crisis, cold war threatening to turn hot at any moment, double-digit mortgage rates.... and Disco.

> The '70s were not hopeful

Civil Rights Activists protested against Apollo 11 at the Kennedy Space Center in 1969, and "Whitey on the Moon" was released in 1970.

Re: Artemis II safely splashes down

#213
post #146

Earlier quoted context omitted.

This is underselling the risks. On top of the many trajectories which push them into unrecoverable situations, leaving them stranded in orbit, there can be trajectories where the moon gives a gravity assist strong enough to fling the spacecraft into escape velocity, fulfilling the OP. In fact, the trajectory they chose for this mission exploited the opposite effect to yield a free return without propellant expense. I…

The amount of things that would have to go wrong for the craft to get an accidental gravity boost and be ejected would be significant. I feel like the original claim paints the whole thing as on a knife edge and barely achieved by virtue of not making a single mistake. In today's age with so many moon landing deniers and worse I feel like we should be specific about where the actual dangers challenges and unknowns th…

The moon's gravity turns out to be "lumpy" because its density is not constant. This was detected by the Apollo missions and caused them to make errors in orbit calculations. This source of error could have influenced the flyby.

Re: Artemis II safely splashes down

#214
post #193

Earlier quoted context omitted.

The amount of things that would have to go wrong for the craft to get an accidental gravity boost and be ejected would be significant. I feel like the original claim paints the whole thing as on a knife edge and barely achieved by virtue of not making a single mistake. In today's age with so many moon landing deniers and worse I feel like we should be specific about where the actual dangers challenges and unknowns th…

Yes, this is a fair point. I agree that orbital mechanics is trivially easy compared to everything else. The chances of a math mistake in particular are null, these trajectories have all been calculated years in advance.

The lumpiness of the moon's gravity is not well mapped out.

Re: Artemis II safely splashes down

#216
post #162

Earlier quoted context omitted.

Nice article, although I'm not so sure about this part: > 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…

> one more known source of risk to eliminate. How could they have eliminated that risk?

The risk couldn't have been entirely eliminated, but most likely the external tank insulation could have been modified to at least reduce the risk of chunks breaking loose and damaging the thermal tiles during launch.

Re: Artemis II safely splashes down

#218

Earlier quoted context omitted.

Yes, and the memories of Apollo are made rosy by hagiography. I even wrote an entire thing to explain why, https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri... (yeah, shameless plug, sorry - it's more for the citations than not. You can read the standards and reports I've linked to) But if I'm allowed to repeat myself from elsewhere in the thread and the meat of the above thing, It's physically not possibl…

I often think about the shuttle program in relation to all these crazy complicated, wildly expensive, and incredibly fragile space telescopes we're sending to LEO or the Earth-Sun L2. Would be damn useful to be able to repair/upgrade these things like with Hubble. 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…

Really? Seems like it would be cheaper to build extra telescopes (economy of scale). When one of them breaks, just launch another.

Re: Artemis II safely splashes down

#219
post #206

What is coming into view from the top center at 08:26:25 [0], right after the commentator says, "the weather conditions remain go"? It stays visible for more than seven minutes before disappearing behind the horizon. [0] https://youtu.be/X9Miy8ngusQ?t=30382

The Moon.

Re: Artemis II safely splashes down

#220

Earlier quoted context omitted.

This was the farthest humans ever travelled from earth, even farther than apollo 13. Intuitively the farther you go the higher the risks are

Landing on the moon is enormously riskier than simply going further out.

I'm answering the claim about Artemis being more dangerous than the space shuttle. Obviously landing on the moon is a lot riskier.
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