RCgothic

Same thing with some images from Michael Baylor

If we're concerned about regolith excavation by engines, are we also concerned about the impact of crasher stages?

Well I reckon someone is going to have to come up with a way to do large scale carbon removal at some point. And I think whoever comes up with a way of doing so efficiently is going to make a lot of money in future getting paid to do so by governments. Personally I think extracting it from sea water might be the way to go, as it's easier to process large masses of water than air. If Musk wants to learn how to do it to produce rocket fuel I'm all for.

So it's not $10B extra after all: Reeks of corruption as well, IMO.

An extra $10B for the program would be nice. An extra $10B before the "favoured" bid lost would have been nicer.

The difference between govt and a private company is that a govt must count the cost of every penny spent to taxpayers, but a private company never has to pay back its development capital as long as it can service the interest.

34 engines at <$1m each plus tanks so cheap SpaceX can afford to build them as GSE instead of COTS. For 300mt+ to LEO. And because private capital never has to be paid back, only the interest needs to be included in the launch price. This may be an unfair way of comparing SLS to SSSH, but taxpayers have different standards to private investors. And whereas STS required rapid reusability to be truly revolutionary, SSSH is already revolutionary even before considering the benefits of reusability.

Oof.

I would expect BN3 to be static fired without SN20, but flown with. If BN3 RUDs then the next test needs to wait for BN4 anyway, by which time SN21 will probably be ready. So it won't matter too much if SN20 was on top of BN3 or not. But if SN20 is up top, they get more data.

They wouldn't be testing the same thing. Flight data is not as good as teardown data. Being able to teardown SN15 may have made SN16 and 17 unnecessary. Whereas they can learn new things from SN20/BN3's orbital flight. As testing and flying SN16 or SN17 will interrupt work at the launch site it may be better to not push ahead with 16 and 17.

And all of this presupposes the Sabre engine actually works. Does it?

We think that in order to go from up to belly down in a controlled manner a kick from the raptors is required. Therefore they can't just coast to apogee, which means they have to keep the speed down so as not to exceed the altitude limit.

Starship is intended to be a controlled vehicle. It'll be able to deorbit with Raptors, or RCS if necessary, or even orient for maximum drag. It'd take a major failure for it to be an uncontrolled object. And the initial orbit could indeed be low to decay within a few orbits That's quite different from launching something to orbit with no control at all.

I think it's increasingly likely that BN2.1 isn't a thing. Just a prototype intertank bulkhead and nothing more. SN17 also seems decently close to completion. There's a real question mark over whether it will fly though. It'll probably depend on how the schedule works out. If 16 is delayed or 15 can be made ready for flight again, then the probability of a flight for 17 goes down. I'd expect we'll start seeing parts for SN21 shortly.

And Russia is being surprisingly open with their tracking data as well.

Doh! I meant Mars of course.

If not now, when. The hardest step is the first. Anything more than 10 years in the future is effectively "Never".

A launch site is mostly exclusion zone anyway. It's not exactly a high impact development.

Sometimes a big infrastructure project comes along and people have to move.

If it comes to it that we're so short on space that we have to industrialise deserts, then that is a future from Blade Runner rather than Star Trek. If we want to preserve our planet in its current form then we cannot use up all the space. Arguably we have already used enough space that there will be unpleasant consequences once the initial inertia wears off.

This is a variant of the "collect the exhaust" idea that we've been over previously. An object cannot propel itself by pushing on itself.

Well. That'd be unexpected.

SpaceX statement on yesterday's flight. Interesting detail on transition to header tanks *before* the kick flip. I think I've seen it mentioned before, but it's been so subtle on viewings of previous flights. (Not that we saw anything this flight) "Starship Superheavy (collectively referred to as starship)" is such an awkward terminology. I am personally never going to refer to it that way. As far as I'm concerned: Starship is the upper Stage. Superheavy is the booster. Starship Superheavy is the full rocket. "The Starship System" is the full ecosystem of starship variants and booster. Clearly they missed an opportunity to refer to the combined rocket as SuperStar.

No, it's me that's mixed up. Multiple private flights!