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Re:Where is my von Braun wheel? by PaulHoule on Thursday July 03, 2025 @11:41AM (#44456186)
Starship to LEO is technologically conservative -- it's hard for me to believe that something like that couldn't be made to work. The uncertainty is that there's not a big market right now for launching things that size but the hope is that the low cost creates the market and maybe Starlink bootstraps it. If it succeeds as an LEO cargo hauler it can be successful without getting man rated or perfecting refueling.

Refueling to go father is technically risky and the performance often not that exciting. If you aren't able to refuel on the Moon, Starship lands and returns roughly 3.5 tons, not better than the Apollo LEM which a much larger vehicle that is tall and tippy -- landing on inner solar system bodies that it is covered with boulders.

Now it might make sense to put a full load of cargo on it, leave it on the Moon and use it as living space, storage tanks or something, but that's not the plan right now. Refueling on the Moon looks tough: water on the moon looks like a good bet, if we're lucky we find frozen carbon sources at the poles or in asteroid residues on the surface [1], but a hydrogen-oxygen rocket looks like a surer thing.

As for alternatives to local nitrogen there is: (1) producing it by nuclear processes which looks tough and (2) various other alternative breathing gases such as Argon, Helium, SF6, etc.

[1] Not clear though if we want to spend any of those on reaction mass or incorporate them in a circular economy. Actual colonists would see it differently than flatlanders. (See The Moon is a Harsh Mistress and The Martian Way)

Re:Where is my von Braun wheel? by dylan604 on Thursday July 03, 2025 @12:04PM (#44456445)
> The uncertainty is that there's not a big market right now for launching things that size

Is that true? It seems like there have been the want of lifting large payloads that must be shrunk to fit the actual launch capabilities. This usually means sacrificing so the thing that is launched is not what was really wanted originally. I think the market is there and just waiting for the thing to work.

Re:Where is my von Braun wheel? by PaulHoule on Thursday July 03, 2025 @12:19PM (#44456614)
You may be right. The fact is that Falcon 9 was aimed straight at a huge market. So far SpaceX has been brilliantly successful when it has focused on immediate commercial markets.

When it comes to things like space telescopes, a cheap 100 tons to LEO would change the paradigm of how things are developed completely. When it comes to deep space missions that are a one way trip it’s not clear Starship does better than something like the SLS which was cost optimized (see big dumb booster)

The way Starship is being developed, with failure being very much an option, could get to LEO with cost optimizations. Mars is a different animal —- if takes 10 tries to stick a landing you’re going to wait 25 years.

The key problem of deep space colonization or exploitation is the long turnaround time. I did an unpublished study of the problem of turning asteroids into solar sails and concluded that it would be impossible if you disn’t have a physical twin in space near the Earth to teat anything (like fixes to problems) that needs testing. The problem of landing Starship without chopsticks could be tested exhaustively at White Sands, for instance.

Re:Where is my von Braun wheel? by schiffern on Thursday July 03, 2025 @01:10PM (#44457160)
Off topic but FYI I tried to sign up for your newsletter from the Ontology2 homepage and got the following error (iOS/Safari):

  403 ERROR

  The request could not be satisfied.

  This distribution is not configured to allow the HTTP request method that was used for this request. The distribution supports only cachable requests. We can't connect to the server for this app or website at this time. There might be too much traffic or a configuration error. Try again later, or contact the app or website owner. 

  If you provide content to customers through CloudFront, you can find steps to troubleshoot and help prevent this error by reviewing the CloudFront documentation. 

  Generated by cloudfront (CloudFront)
  Request ID: zte7dpy79ryEUqFA5UUBPv4Yl4t6NIL4lyHvs6yqTcdr8wCrXG5xHA==
Re:Where is my von Braun wheel? by PaulHoule on Thursday July 03, 2025 @01:44PM (#44457469)
Thanks for heads up. That site was part of a serious marketing effort when I was trying to start something up and I haven't really thought about it in years. The home page made sense at the exact time I made it but is a bit of a non-sequitor now. I've got to get a lot of my notes published there.
Re:Where is my von Braun wheel? by schiffern on Thursday July 03, 2025 @01:49PM (#44457526)
Thanks, looking forward to whatever. As a fellow nerd with similar interests I literally "want to subscribe to your newsletter" lol. Cheers.
Re:Where is my von Braun wheel? by PaulHoule on Thursday July 03, 2025 @02:08PM (#44457706)
Immediate term you should just send me an email to get in touch.
Re:Where is my von Braun wheel? by schiffern on Thursday July 03, 2025 @03:05PM (#44458212)
Email sent, thank again.
Re:Where is my von Braun wheel? by ceejayoz on Thursday July 03, 2025 @04:18PM (#44458820)
> something like the SLS which was cost optimized

If SLS is "cost optimized", I shudder to think what a non-cost optimized rocket would look like. One launch a year at $2.5B a pop?

Re:Where is my von Braun wheel? by PaulHoule on Thursday July 03, 2025 @05:59PM (#44459518)
"Like SLS" in that it is a huge expendable booster, not "Like SLS" in terms of development process.

This book

https://www.amazon.com/Shuttle-History-Developing-National-T...

has wonderful illustrations of many of the hundreds of designs they considered before settling on what was to be the Space Shuttle and also talks about late 1980s studies that considered various ways of putting together Space Shuttle parts to make different vehicles (say a big-ass orbiter with more engines, a bigger ET and more SRBs) The hope was that you could reuse the development work that went into Space Shuttle parts but it seemed like anything you made out of Space Shuttle parts was unaffordable no matter what you tried.

You could certainly develop parts that are cheaper on a per unit basis but would it be worth developing them for the number you would make?

The US doesn't really have an attractive answer to getting to the moon or for aggressive deep space missions, Starship doesn't look great. Growing up in the 1980s I read the "Science Fact" columns in Analog Science Fiction magazine and was told that NASA sold us out and we could have had a much more intensive lunar program but really the architecture Apollo used was brilliant and much more achievable than everything else they considered.

Re:Where is my von Braun wheel? by avmich on Thursday July 03, 2025 @06:35PM (#44459709)
> The US doesn't really have an attractive answer to getting to the moon or for aggressive deep space missions, Starship doesn't look great.

Starship is almost an assisted single stage to orbit (ASSTO), the first stage gives rather modest part of total characteristic velocity.

This allows the second stage, Starship, to have a lot of delta-v. I guess it was optimized for Mars operations. Yes, Starship requires refueling for any flight away from Earth orbit, but in exchange for that it packs significant delta-v, so sending large payloads away from Earth - after refueling - becomes easier. That includes Mars, Moon, asteroids, the rest of the Solar system.

I think this makes Starship design rather good.

Re:Where is my von Braun wheel? by glompers on Friday July 04, 2025 @12:37PM (#44465937)
This is the revised, expanded 3rd edition of that title:

https://price.dealoz.com/prod?gtin=09780963397454

Re:Where is my von Braun wheel? by meepmorp on Thursday July 03, 2025 @05:23PM (#44459317)
optimized to cost a lot