mikegarrison

Water deluge has been used for 50 years, at least. The question is not "how did SpaceX design a water deluge system so quickly?", but rather "why did they think they didn't need one before?"

I assume he was confusing km/s with km/h.

Coriolis has approximately zero effect on such scales.

Radius of the Earth is more than 6000 km. Even an 8km mountain peak is thus about 0.12% different in height versus sea level. This is why gravity is essentially the same.

With most of the fuel burned, almost certainly the rockets make up the bulk of the remaining mass of the booster.

The ship was not headed for an orbital trajectory anyway, even if it had completed its burn.

If STS had blown up on the first launch in the first stage, and then had blown up again on the second launch in the second stage, absolutely no one would be claiming these were great tests and a great learning experience. The goalposts are different for SpaceX -- among the SpaceX fans, anyway. But among the general population, don't expect the "whatever happens, we learn something" thing to be a popular viewpoint. If the third try works, people will no doubt point to the first two and say, "See? Learning by experimentation works." If the third try fails, people will no doubt be saying, "Three times! This rocket is a disaster!" At least they didn't have the same failures twice.

They are large chunks of metal -- titanium, IIRC. Likely would survive an explosion like that more or less intact.

I'm surprised they didn't reshow the flight. Is there a way to watch a replay?

Hmm. I was busy playing BG3 and forgot this was going to happen. I tuned in, and the second stage was burning. But they said the first stage was destroyed? And then, well, they lost contact with the second stage and said it appeared as if the FTS had activated. That seems like a pretty serious issue -- at that point in the profile shouldn't the FTS be safed?

The rules against political discussions prevent me from answering most of this. I will say that EASA charges applicants a fee for them to do the work required to certify an aerospace vehicle. To the best of my knowledge, FAA does not. Both extensively rely on the companies involved spending their own money to do the testing and analyses that the regulators require. They also both allow companies to pay their own employees to act on behalf of the regulators. In such cases the employees are sworn by law to be acting on behalf of the government and not the company that is paying them.

WIW in the current Congressional environment is precisely nothing at all.

We could discuss funding levels at the FAA, but that would be political.

Got news for you, unfortunately. Eventually the whole universe will be dead. The issue here is not whether humanity will survive infinitely far into the future, because it won't. The issue is whether leaving Earth might delay our species' inevitable extinction or whether it might, instead, hasten it. And if it does something like trigger wars, that might be a real issue. If you can redirect an asteroid away from the Earth, that means you can redirect one toward the Earth, too....

With Musk himself being the one who determines whether they make sense? That's not exactly "regulation". Or maybe just of survivor bias. There are other companies that have tried the "go fast and break stuff" idea that have ended up ... broken. In the great dot-com boom of the late 90s there were a lot of companies that burned through all their cash trying to buy market share for their great internet business idea. Some of them became Amazon and Google. Some of them became Pets.com and Webvan and eToys.com.

Not really a definition of "insane". I mean, I suppose it can be. We use the word quixotic to mean someone obsessed with a goal that is probably meaningless and may be impossible, and Don Quixote was, if possibly not "insane", clearly not thinking correctly. I am not going to judge Musk's sanity, because a) I'm not qualified for that, and b) I don't know him. But certain aspects of his public behavior (and his fanbase) are extremely unappealing to me. I am reminded of Howard Hughes (who was before my time, FWIW). Or the fictional Citizen Kane. Sometimes giving people no limits (like fantastic personal wealth and power) has bad effects on them. Or possibly, if it is not a cause, it is at least an enabler. I feel like I'm watching someone fall down a rabbit hole to a very specific kind of wonderland. And not a very nice wonderland either. The kind populated by Sad Puppies and Gamergate hashtaggers and Great Replacement believers. But Musk != SpaceX, sort of. And yet, he has such a cult of personality (and so much ownership and control of the company) that Musk very certainly is entangled with the fortunes and future of SpaceX. Possibly, if it became necessary, SpaceX could end up independent from Elon Musk. But at the moment, it is hard to visualize a path to that. Dinosaurs were on the Earth for over 150 million years (not even counting the birds). That is roughly 1000 times longer than hominids have been here. I think that if we last as long as they did, we will have done better than I expect.

Just gonna drop in here that SpaceX using Tesla cars for transporters and X-exclusive broadcasts and the like is exactly the sort of behavior that led to anti-trust laws being written in the first place. And since the ownership of those different companies is not identical, if one company gives something to another (such as SpaceX giving X valuable exclusive content), that potentially constitutes transferring value from one set of minority shareholders to a different set -- probably without their consent.

One characteristic of laser drilling is that it has a tendency to make conical holes rather than cylindrical ones, and we used to use that to our advantage with combustors. We would drill the cooling holes from the inside of the combustor, thus making each hole slightly diffusing, which helped keep the cooling air at the wall of the combustor where it was needed.

Folks, you know that laser drilling is a thing in real life, right? Used in industry all the time. No need to be guessing about this. https://en.wikipedia.org/wiki/Laser_drilling

The book is written by a cartoonist and a worm biologist. They in no way claim to be providing a definitive "conversation ender". What they are doing is attempting to be a conversation STARTER -- about issues that are often handwaved over by space colony advocates.

Oh, and also? You've got to love a book that is willing to discuss a hypothetical war on the surface of the moon between Muskow and Bezostralia.

OK, just finished the book, and in the end ... they make a plea to all their fellow space fans to forgive them for coming to conclusion that this will be really hard to do and possibly should even never be done, but definitely should not be rushed into.

The book is titled A City On Mars, but they discuss the Moon, Mars, and space habitats.

And of course they discuss this, but their point is that it is nearly impossible to imagine any kind of wide-scale disaster on on Earth that would actually make it less habitable for humans than Mars is right now. No air, no nitrogen, toxic dirt that sometimes blows in planet-wide dust storms, high levels of radiation, low gravity....

And I have stated before that adding landing gear to an aerospace vehicle as an afterthought usually does not go well. They do have some idea how to do landing legs on the outside of a booster though, so it's probably not outside their ability.