sh1pman

What "principles of safety in space" do these agreements establish? Safety from what, falling rocket stages?

There is no reason to be depressed. People disagreeing with you on an Internet forum is such a minor thing in comparison to real life issues. And people here are very polite and respectful (unlike e.g. Reddit), nobody is going to insult you for your opinions!

Yeah, mixed up the two numbers. Should be mass to GTO for both rockets.

Maybe a little, maybe a lot. Real number may be up to ~50% higher.

Yeah, that's why it seems strange to me. Other rockets with hydrogen upper stages seem to be performing better on high energy orbits. For SLS Block 2, TLI/LEO mass ratio is 0.35. For Atlas V 551 it's 0.47. For Delta IV Heavy it's 0.55! NG is a black sheep in this family, performing even worse than a FH with kerolox US. The only logical explanation for it is that its upper stage has a terrible wet/dry ratio.

Is there any info on NG S2 wet/dry mass and BE-3U Isp? I’m asking because the officially released payload mass to GTO seems too low for NG. To LEO: 45t; To GTO: 13t. Compare it to FH: 63t to LEO, 26.7t to GTO (expendable). The reason why GTO throw seems too low to me is because NG has BE-3U-powered hydrolox upper stage with higher Isp compared to MVac. Payload mass should fall off slower for NG, and its GTO throw should be a higher fraction of LEO throw compared to FH. In reality, however, for NG this ratio is 0.29, and for FH it’s 0.42, which is very odd. Is wet/dry mass ratio of NG S2 really that bad?

Starship Factory Manager. At first there’s a plain field, so you need to build tents, workshops, etc. Research new tech to build SNs faster or improve their chances to survive the milestones like pressure tests, cryo fueling, then static fire, short hops, 20km flights, and finally, orbit. The goal is to make orbit in the least amount of time.

Probably best to mine rock on the Moon and send materials to space via mass driver. But industry on the Moon would need to be set up first.

So, to build this thing in orbit (10 million tons) they’d need 67k launches for ~$100B total. That’s not unreasonable, DoD budget is ~$700B a year.

Sure, but if one launch can lift ~500 Starlink sats to orbit, that’s still not a lot of launches. I think they expect to open the market for some really big projects in space, like Moon bases or ring stations that require absurd amounts of material to build. But who will fund those?

What kind of fly rate will they need to have to drop the cost to $1.5M/flight? It sure sounds great but where to find so many payloads?

Well probably not today.

About the same volume as Orion. And they’ll have a bit of gravity, so it’s somewhat more comfortable than the capsule. Yeah, hard to beat that luxury flying skyscraper.

Also, Dynetics is based in AL, so the choice is almost certain.

They’ll need to master aerobraking from high energy orbits anyway. Multi-pass is useful for Mars, don’t need to commit to landing as soon as you arrive. I bet they will grill a few SN’s while figuring it out.

Sometimes I wonder what the hell is going on in his head.

They’re making a new Starship every 3 weeks, improving the design or manufacturing with every new vehicle. 4 years is more than enough time to land it on the Moon.

Well, that didn’t age well, did it?...

What did they do to Starship? It doesn’t look like it’s going to return to Earth.

It’s a bit funny that Starship is kinda vulnerable to the same criticism that SLS always gets: it’s a rocket without a clearly defined mission. It’s designed to do everything. You can call Mars colonization as its primary mission, but who knows when it’s actually going to fly there (and with people!). The difference between the two super-heavy rockets is that Starship is going to be much more capable and 200+ times cheaper to launch. What impresses me the most about Starship is that SpaceX is doing something that only government agencies of superpowers could do before (super-heavy, reusable rocket and spacecraft), while also doing it alone, using its own money.

Airlines will always be safer than rocket launches. For the simple reason that airplanes won’t stop flying, gradually becoming safer, improving safety standards and regulations after every big incident. Rockets won’t ever catch up, always lagging at least several decades behind airliners.

There are two layers here. On the first one, they just try to calculate how much money SpaceX saves from reusing the first stage. The infographics could be done better, lots of repeating info, slides 2-4 could be combined into one. On the second layer they’re implying that NASA overpays SpaceX for Dragon launches (160M vs 104M), and this allows them to set the price for commercial launches lower than the 71.5M price of a new rocket. Therefore, even without 1st stage reuse SpaceX can afford to charge significantly lower than 71.5M.

GK’s attempt at working out the economics of reusable rockets by SpaceX.