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Artemis II safely splashes down

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Re: Artemis II safely splashes down

#191
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.

Have you checked the news recently?

Re: Artemis II safely splashes down

#193
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…

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.

Re: Artemis II safely splashes down

#194

So the new heat shield works just fine, and NASA still knows things better than arm-chair aerospace engineers? Safety third.

We'll need a post mortem to know what the margin of failure was. This said they had made changes since the first flight so we'd expect less to no damage this time.

Re: Artemis II safely splashes down

#195

Glad that they're safe and sound. 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 i…

> Artemis acceptable crew mortality rate is 1 in 30.

How did they arrive at that number?

(Eg. Did they arbitrily establish the target at the outset? Or did it evolve by gauging the projected failure rate of their core mechanical etc. systems as those began to take shape, then establishing a universal minimum in line with that, to achieve some level of uniformity and avoid drastically under/over-engineering subsequent systems?)

Re: Artemis II safely splashes down

#196

Earlier quoted context omitted.

> Artemis acceptable crew mortality rate is 1 in 30. 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?

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

They could go twice the same distance, the risk would be roughly the same at that point. It's mostly the complexity and changes that make it more risky once the initial trajectory is in place.

Re: Artemis II safely splashes down

#197
post #175

Earlier quoted context omitted.

Hilarious the the intellectual forum downvoted you for being absolutely right. 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.

> The pull of the moon had very little effect. No, it had a very significant effect: it's what made possible the free return trajectory while observing the far side of the moon.

Ok, but no not really. This is incorrect, the “free return” would have happened if they launched entirely in the wrong direction.

Like I said, the gif you saw makes it look that way.

Here is a link that explains it very well. https://youtu.be/MF8IbYbVIA0?t=269

I’ll agree, it seems crazy that it left earth, made it to the moon, and never really left earth orbit at all. That the furthest we’ve been away is still destined to return on its own.

Re: Artemis II safely splashes down

#198

Glad that they're safe and sound. 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 i…

I mean it's the first space crew on an anti-science mission, right?

The point of them being there isn't discovery, it's to try to discourage anyone who wants try to understand and protect the planet that we all rely on for life

Re: Artemis II safely splashes down

#199
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 Father of Disco was involved in the song "Electric Dreams" associated with a film about AI in a love triangle.

Re: Artemis II safely splashes down

#200

Why this was such a big deal? Haven't people reach the moon so many years ago? By this time we should have lunar bases, not cheer so much that we got past the moon at a few thousands miles away.

Because we haven’t had translunar manned flight in fifty years, and this is the precursor to start it up again
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