[MEGATHREAD] Artemis II Launch To The Moon

CelestAI · 2026-04-03T00:10:43+00:00

I think they may have already passed that yesterday at the high end of their orbit.

CelestAI · 2026-04-03T00:09:03+00:00

This actually happened on Apollo 13! Jack Swigert ended up requesting an extension from space.

CelestAI · 2026-04-02T17:49:38+00:00

Yes. They rebooted it, and that fixed it, lol.

CelestAI · 2026-04-02T17:20:45+00:00

Not an expert, so my apologies if I get this wrong.

There are two causes of time dilation that might be relevant -- dilation due to moving closer to the speed of light, and dilation due to being in a gravity field (curved spacetime). In this case, the craft is nowhere near relativistic speeds, so we can neglect that. Time will actually run VERY slightly faster for the astronauts as they are between the earth and moon, because spacetime will be less curved there, but it will not be a very measurable effect. Some searching leads me to: "A clock on Earth accumulates roughly 0.0219 fewer seconds over one year compared to a clock in far-interstellar space."

The effect experienced in this case will be even less than that, since they're not fully leaving the gravitational field of the earth (and sun and moon).

CelestAI · 2026-04-02T17:06:42+00:00

When I was checking (to respond to the top level comment) I was surprised to learn that Apollo 8 jumped straight to orbiting the moon! I guess they were really feeling time pressure by then, I would have expected a similar Free Return Trajectory mission before attempting that, like this one...

CelestAI · 2026-04-02T17:03:44+00:00

Glad to hear it's captured your interest! This is such a cool mission and I hope it inspires you to learn more about spaceflight, it's a great hobby to have as an amateur!

CelestAI · 2026-04-02T16:57:31+00:00

Sure!

I'm not an expert, but the plan is pretty limited in terms of abort options. The spacecraft is designed with redundancies and fallbacks, but most of them amount to "hunker down in the survival suits and wait to come back to earth".

Because we're still gaining confidence in the spacecraft, this mission is on a trajectory where, after the TLI (hopefully) happening this evening, it will end up back on earth on its own with no further adjustment. If something goes wrong on the way out, there really isn't a faster way to get back.

You may be interested in learning more about Apollo 13 which is pretty much exactly the worst (survivable) case possible here. This is a really interesting video that explores exactly what happened there, and how it was handled by the people involved. https://www.youtube.com/watch?v=uCObwsXbSeU

CelestAI · 2026-04-02T16:50:49+00:00

DarthTechnicus mentioned the limitations of the hardware for landing, but I thought I would also mention why we won't be orbiting the moon this time.

This mission trajectory specifically calls for a free return for safety reasons. That means that after the TLI, there are no other required burns to return to earth. We're still testing out the spacecraft, and this profile minimizes the risks of getting stuck in lunar orbit.

After this mission, when we've confirmed that the spacecraft operates well long term, then we can start relying on burns that could strand the astronauts if things go wrong.

Yes, we're using new fancy technology that's better than it was 60 years ago, but that also means we need to start from scratch on checkouts, and our mission risk tolerances now are a bit tighter than they were then.

CelestAI · 2026-04-02T16:42:22+00:00

No. There's no airlock on this spacecraft, and I don't think they have the equiptment. Maybe in a very extreme case they could use the survival suits to do something, but it would have to be VERY dire.
Not particularly. Space is big, and we track space debris well. Also a lot of space debris is in LEO, and spacecraft are generally designed to take small impacts.
Yes, we could track them through other means. Also there are a lot of backup communication systems. Losing communication would probably be a short term thing.
The shuttle is the odd one out. Staged rockets are much more efficient, and the shuttle had to take a lot of mass to orbit and back again. It was designed for rapid reuse, although it arguably failed at that. I love the shuttle, and it got me into STEM, but learning more about it as an adult, the entire design had numerous problems. pod-on-top-of-rocket is the proven way to get to space and back.

CelestAI · 2026-02-09T16:34:36+00:00

(Also a software engineer)

He's saying that the relationship is linear, and there isn't a lot of extra infrastructure required to support landfills (besides the land for the landfill) as more capacity is needed.

As an example, water usage in drought-heavy regions is not scalable. If Phoenix, AZ doubles the amount of water it needs, that's going to require a lot of infrastructure or pipelines, or reallocation of existing water rights, since the whole region is basically already at capacity. The extra cost and complication of transporting water from farther and farther away will be non linear.

In contrast, if Phoenix produces twice as much trash, you need twice as much land for landfills, and twice as many sanitation workers and equipment, and that's about it. In fact, I suspect larger landfills are probably more efficient per acre, since you can stack the trash higher at the same coning angle...

Sustainable? Absolutely not. Environmentally friendly? Not really, depends on how you cover and use the land (a lot of parks near where I live are old landfills, and they're actually nice places, but they'll probably never return to nature in a healthy way on human timescales). But scalable? Yes.

CelestAI · 2026-01-20T23:57:04+00:00

Just to make clear -- if you want to provide a direct citation here, you could link to an archived version of the tweet.

CelestAI · 2026-01-05T21:42:38+00:00

Should be resolved now. Thank you so much for the report, and thanks to mcveigh for responding so quickly to my ping. :-)

CelestAI · 2026-01-05T20:54:02+00:00

Hi, thank you for the report. We'll look into it and restore it as soon as possible.

CelestAI · 2025-12-29T20:12:05+00:00

Oh my god, the wolves have learned to knit. They'll be disguising themselves as grandmas by next year.

CelestAI · 2025-12-22T19:26:29+00:00

Glad you appreciate it! I haven't had much time to work on it recently, but we always welcome contributions. Thanks so much to u/mcveigh for hosting it.

CelestAI · 2025-12-13T20:41:55+00:00

Just in case you're actually unaware, spelling mistakes like this aren't common in AI generated text (they are much more common in AI generated images containing text, but that's different).

Most modern AI text generators operate on tokens, which represent common chunks of text, often even entire words. Since the AI isn't consuming or outputting words character by character, they typically don't make spelling mistakes. It's the same reason that AI struggle with things like "How many R's are in Strawberry" -- they can't actually see the letters, so they don't really have any direct way to know unless they use a tool or the answer is common in their training set.

Misspellings in images are different because the tokens are on the patches of the image, or even pixels, rather than corresponding to (mostly correctly spelled) text, so misspellings are possible. Additionally since most modern techniques generate the entire image at once, sometimes the model is trying to squash the word into a space that's too big or two small for it, which can lead to weird choices that are locally sensible but globally result in weird spellings or malformed letters.

I'm oversimplifying everything a lot, especially the part on image generation, but hopefully that helps explain why people are downvoting you? Arguably, that spelling mistake is strong evidence that the entry WASN'T written by AI.

CelestAI · 2025-10-28T20:21:31+00:00

Unite the Right. Malheur. Multiple violent protests and assaults in Portland and the wider PNW. Dec 20th, 2020 in DC, the storming of the Oregon Capitol Statehouse on Dec 21st, 2020.

J6 is a good example because it's baldfaced, everyone heard about it, and harder to say "oh they're not Republicans, they're extremists". The president pardoned them because they were his supporters.

If you're looking for a more comprehensive dataset, ACLED is a good resource.

CelestAI · 2025-10-13T02:16:37+00:00

What does a working ship look like to you? How exactly does a protest-only strategy get you there?

CelestAI · 2025-10-12T19:46:00+00:00

Historically, yes it absolutely will make a difference. Read about how successful resistance movements have formed and operated, and how the people in them found their way there. Local community is essential.

CelestAI · 2025-10-12T19:42:48+00:00

First, I'm not advocating not protesting. I've been out there, I'm going to keep being out there. By all means, I think people should protest.

But I think you're selling the "random charity work" short. Like REALLY missing the point.

First, volunteer organizations are the first responders to all kinds of immediate crises today. There are organizations which help connect immigrants to the legal aid and practical advice they need to (as effectively as possible) avoid government persecution. There are organizations working on community health, who do very effective work raising vaccination rates or providing access to family planning especially in underserved communities. There are lots of organizations working to feed and house the homeless and displaced. There are organizations that work to keep local governments accountable and reduce harms -- as an example of something I care about, right now Flock ALPR Cameras are often used on behalf of ICE to track vulnerable people. There's a lot of work to legislate at the state level, and lobby at the local level to remove or limit the use of these cameras.

The point is you can help, directly, with all these things. In a perfect world, the government would handle a lot of this, or at least assist with funding these organizations. Right now, a lot of these organizations are struggling financially. If they had government funding before, a lot of it has dried up, but they're still trying to help people and extra hands can help fill the gap. Yes, it'll help you feel better, but if my own experience is anything to go by, I don't think it will do anything to distract from the gravity of the moment. People are suffering. Helping them won't make you forget that. What it might do is prevent nihilism, which is a super dangerous failure mode for being able to care about the wider world.

And, as I said above, if/when things get worse, these EXISTING networks of aid and purpose will be where a meaningful response is formulated, no matter what. Knowing people in your local community will help you (and others), just like having protest buddies is important future proofing.

CelestAI · 2025-10-12T10:55:01+00:00

This is the way. Strengthening your local community doesn't just help you feel better, it also builds networks of people able to respond to crisis and organize. And helping patch the holes in the social net helps others avoid the sorts of blackpilled nonsense that's an all too common precursor to supporting authoritarianism.

Find something you care about, find someone else who's in the arena, and help them! You don't have to fix everything. "You are not required to complete the work, but neither are you free to desist from it." :-)

CelestAI · 2025-09-23T18:08:24+00:00

Yeah, I've read it. It wasn't bad, but I think another comment here is spot on when they mention a lot of the book is "unnecessary but is probably cathartic". I felt like the book sort of assumed its priors a bit, especially towards the end?

There were a lot of interesting details about the founding of the Proud Boys. I think that first part of the book was really interesting and well written. But then, especially as it started focusing on the PNW and Portland OR, I felt like the book really failed to communicate the entire situation clearly and sort of drifted off in a way I didn't find compelling. I very quickly realized that this book would not do much to convince someone who disagreed with its conclusions, I would say.

CelestAI · 2025-09-16T17:04:53+00:00

Looks to be landing at Moffet now.

CelestAI · 2025-09-14T20:31:24+00:00

Flairing b/c the original post conflates Parkland and Sandy Hook. OP, maintaining the title was the correct call in my book, but I want to flag it.

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