by godelski | 2026-02-06 20:01:06+00:00
> If you're not willing to have 8 starship landings

Your math is WAY off.

You used LEO payload... Their GSO payload is 21tons[0] and the moon is a lot further than GEO. If you use the GSO numbers you get about 37 launches. But TLI (Trans Lunar Injection) is probably closer to 15% LEO payload capacity[0], if we estimate off of Atlas V, so let's say about 50.

Not 8, 50. You're off by 5x-10x.

> I think you misunderstood me.

Look, I don't want to call you dumb, I actually think you're pretty smart. But rocket science is famously hard. Many things are non-intuitive (true for most hard subjects).

I also think you should take a step back here and think about what you're saying. Look at your number of lander estimates here and how far off you are by a simple naive assumption. I get why you made that assumption and I understand why the error was made, but also these are not the kinds of mistakes people make when they have expertise in the domain. I knew it was more than 8 before even running any numbers, I knew it was more than a few dozen. But I also know people frequently make the claim that getting to LEO is the hardest part and that this warps people's perceptions and makes for bad assumptions. You have passion and I don't want to kill that passion, but if you are this passionate then use that passion to drive you into diving deeper into the topic. Don't be satisfied with shallow knowledge, your passion is greater than that.

So I want to address the full

> If you're not willing to have 8 starship landings for power infrastructure, why even bother?

Because 100 launches is a non-starter. There were a little over 300 for all of 2025. It's a big improvement, since 5 years back we barely broke 100, but you're talking about way more. About 100 of those were from China and SpaceX hit 170 total. That's a wildly impressive number, mind you, but you're also talking about 10xing their Starship launches. These things are hard to scale. They've been doing about +30/yr since 2020 on their Falcon 9. Impressive numbers, but not fast enough and scaling Starship will be harder.

> I'm absolutely not saying "this would be easy" (nothing in space is), I'm saying "this is what my sales pitch would be".

So this is why you misunderstand me, and, I think, the conversation. Maybe the "sales pitch" works for people who don't know any better, but it isn't going to work on those with even junior level experience in the industry. The numbers are so off they will set of alarms and you get dismissed. It only makes it worse when pressed that the numbers look even worse.

Because I don't think you're suggesting it would be easy, if you did I would have laughed in your face. But I think you've underestimated how hard it is, even though I think you think it is really hard. There's no limit to how difficult something can get so it becomes easy to underestimate the difficulty. This is just like it is easier to make bad estimates of distance when looking at something very far away, it is easy to think something is 5 miles away when it is 10. This doesn't make one dumb, but rather that we need to more accurately be aware of our level of uncertainty. And in this case, it is pretty high. Why wouldn't it be? There's literally no expectation for it to be unless you're an aerospace engineer working on lunar systems.

[0] https://web.mit.edu/2.70/Reading%20Materials/SpaceX%20%20Sta...

[1] The Wiki says 100k but with in-orbit refueling and there's even a note about needing a better source. So that doesn't really count for our estimates. Saturn V and SLS has a bit better, hence the range in the next line. But also remember Saturn and SLS don't have to do returns... You'll find this helpful: https://forum.nasaspaceflight.com/index.php?topic=49117.0

[2] https://spacestatsonline.com/launches/year/2025