Comment by JumpCrisscross
4 days ago
> Starship "making LEO" is not a significant challenge
Of course it is. I say this as someone who sturdied astronautics.
You’re broadly correct, though. My point is the action shifts to Hawthorne and West Texas for the next year or so. Then pivots back to NASA for Artemis IV.
It’s not a significant challenge compared to what they’ve already done.
Each of those previous tests could have easily gone to LEO running the engines just a tiny bit longer.
OPs point is that they intentionally didn’t.
achieving LEO means you need a relight to have a controlled reentry. You don’t want that if you want to avoid countries being mad at you while you iron out those controls
> It’s not a significant challenge compared to what they’ve already done
I don't know an aersospace engineer, within SpaceX or without, who would agree. When you increase speeds you increase energies faster. That has an effect on everything from pump performance to re-entry physics.
> Each of those previous tests could have easily gone to LEO running the engines just a tiny bit longer
Which risks recovery. Given they were replacing their Raptors in the next refresh, pushing an already-obsolete engine for shits and giggles doesn't make sense when you can get good data on e.g. skin performance.
> achieving LEO means you need a relight to have a controlled reentry. You don’t want that if you want to avoid countries being mad at you while you iron out those control
There is zero indication diplomatic pressure has been a constraint on the U.S. space programmes in the last couple years.
They didn't have to increase speeds, they already achieved orbital velocity. To circularize all they need to do is relight. Relighting an engine is very difficult for an engine like Raptor, but they've already demonstrated relight.
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It is like a runway taxi test on a plane that is fully capable of flight. Sometimes the plane takes off unexpectedly but the plan is not to do it. Starship can do orbital insertion now despite no plan to do it yet.
Spacex explicitly on the streams said they shut off the engines early to avoid orbit. I don’t know why you would argue against them
You’re also incorrect that a separate burn is required for orbit. You only need to do that if you want a circular orbit.
Odd. As a side note, your comment was posted [dead]. I vouched it to restore it back to life.
This is the second time I’ve seen such insta-dead comments. (One was my own, and I thought I did something wrong. Now it looks like there’s some kind of bug in HN that’s killing on-topic comments when they’re posted.)
Your comment wasn’t deep or insightful, but not every comment should be. A simple rejection of a premise is certainly on-topic. So it’s hard to argue that your comment was “bad”. That narrows the possibilities down to a bug in the algorithm. Maybe the mods are experimenting with ML auto classifying whether new comments should be killed or not.
Aww. Thanks. Wonder what I did to piss of YC.
Nothing. Now that I’ve seen it once for me and once for you, both on comments that seemed lightweight-but-harmless, I’m convinced there’s some sort of bug. So don’t take it personally.
Also HN != YC. They’re separate organizations, iirc. When Sam Altman was running YC one of the first things he did was “refactor” HN so that it has editorial independence.
Either way, it would be hard to imagine someone from YC telling Dan “you should boost so-and-so” and him going along with it unless it directly benefitted the HN community.
"Project Gemini has entered the chat." Did I do that right? Anyway, what are we talking about?
> Did I do that right?
Unless you’re trying to make a reference to the Gemini programme. No.
I guess I was a little distracted by the tangent to starship over the orion/Artemis I was disappointed to see that after all these years NASA trying the old trick again and hoping people get excited.
As for spaceX and starship, I haven't kept up with it but I trust it's still putting NASA to shame wrt setting the state of the art.