SpaceX’s Starship V3—still a work in progress—mostly successful on first flight

SpaceX has more to prove before flying Starship all the way to low-Earth orbit.

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[himi]

The satellite view was very cool, but one thing I was a little confused about: they said on the broadcast that they were doing that to be able to inspect the heat shield. But the satellites are released from the top of the ship (the side without heat tiles). Was it supposed to do a flip maneuver after they released, or did they mean they wanted to inspect the few tiles they stuck on the top of the flaps?

I believe the idea is that they deploy the satellites and then use RCS to rotate the ship while in view, in order to confirm the state of the heat shield before attempting re-entry. If a ship suffered damage during launch or in orbit, that could be used to determine whether to attempt a recovery or go for a splashdown.

I don't think this deployment was intended to do that (particularly given the engine issues during the launch - they probably dropped a bunch of potentially risky on-orbit tests so they could make sure they got the ship re-entry results), it was mostly just a tech demo to prove the core idea, as well as put some starlink v3 components in space to do basic functionality tests.

 

[himi]

I don't quite understand why this is important for flight decision making. As diagnostic data for confirming why a ship was lost, sure, yes, that's still quite useful. But if the Ship is going to be lost, it's not like there's some rescue plan that will save it for less than the cost of just manufacturing a new one, and the way that landings work, they aren't targeting the launch site until they've confirmed engine relight, so if it fails it will crash into the ... oh, hmm, I see. It's only the booster that reenters from the oceanic direction. The ship arrives at Boca Chica from the East, meaning that it fundamentally has to pass over a lot of populated land (even if it dodges major population centers).

So I guess if the inspection shows that Starship is missing enough heat tiles to have significant risk of failure during reentry, they are going to target open ocean to reduce the risk of it failing over land? It's not about reducing the risk of losing a Starship. It's about reducing the risk of a Starship failure scattering debris over land. I wonder what the decision threshold will be. Is a 1% chance of failure over land enough to dump a 99% survivable Starship in the ocean?

Exactly - and remember, this isn't just about the test program, this is something targeted at operational flights over the long term.

I expect they'll be pretty cautious about their decision making until they get a lot more experience, even though it's been made abundantly clear by the test program that a ship which can still control its re-entry is likely to make it all the way to the flip maneuver (I still shed a tear thinking of The Little Flap That Could . . .)

This thing is big, tough, and has lots of chunky hardware - debris hitting an urban area would not be pleasant. The only positive, really, is that the most toxic things on it are likely the batteries, there's no concerns about any of those crazy-arse-toxic hypergolics.

 

[himi]

Not necessarily. Yes, the Sun will expand, but the Earth could be moved before that happens. Every asteroid that flies past Earth changes it's own and the Earth's orbit. Since the Earth is much more massive, it's orbit doesn't change much.

But we could intentionally send asteroids past Earth to add orbital energy, then reset the asteroid path with a flyby of one of the giant planets. Repeat lots of times and you can move Earth farther from the Sun so it can survive the Red Giant stage of the Sun.

Now /that's/ some serious long-term thinking!

Its even applicable for the really long term, once the red giant sun collapses to a white dwarf - move Earth close enough to be able to retain a workable surface temperature . . . though I'll have to hand-wave any questions about a livable surface environment, given the emission spectrum of a brand new white dwarf.