[skybrian]

Why should we believe that Starship launch costs will be that cheap when we don't believe Musk's other numbers? Where does that number come from? Has anyone looked into it?

It doesn't cover launch costs directly, but here's a bearish take on reusability of the second stage:

https://mceglowski.substack.com/p/how-should-we-think-about-...

[somenameforme]

Yes, it's been extensively analyzed. Space is a massive industry with a huge base of people, disproportionately made up engineers and the like, who love digging through the nitty gritty of pretty much everything. Nasa space flight forums [1] are the analog of hacker news, but for space. That link is just for discussion on Starship, and currently has hundreds of thousands of posts.

[1] - https://forum.nasaspaceflight.com/index.php?board=72.0

[skybrian]

So what's the consensus? Any article in particular that you recommend?

[somenameforme]

Peruse the forum. There's a topic on near everything relevant you might imagine. If you want a topic starting from a bearish premise, here is one. [1] In general I think there's little doubt that Starship is viable, but the exact implications are open to a wide range of speculation. Prices are going to go down, and payload sizes are going to go up, but the exact degree is open to speculation varying by orders of magnitude.

[1] - https://forum.nasaspaceflight.com/index.php?topic=63166.0