> How far out would you say that is?

Really hard to say. Everyone who does space stuff talks with the same level of optimism as Musk but historically they deliver less.

But for what it's worth, I don't think Musk's going to reach Mars except in an urn, baring some surprise development in anti-aging medicine. Even though their progress is rapid by the standards of the industry, they are still slow in terms of natural human lifespan and his age.

> Have you sketched out the net present value calculation for an investment in spacex today based on that?

IMO, their market cap should be around $200bn at the moment. That's mostly Starlink, so if there's a Kessler cascade *or* if China makes a competitor that goes down to about $80-100bn

The long-term stuff about Mars or turning the moon into a factory for modular data centres is too far into the future to be worth considering.

That was my general impression. They did amazing work to totally change launch costs (with more on the way). But launch was a limited market. The low costs have and will grow it, and starlink will grow it, but not enough to justify this value.

In investing it's critical to think about things probabilistically, rather than trying to just guess the future. "Fooled by Randomness" is a great book on this. In a scenario like this it's especially critical, because in the case where Starship fully delivers and the next great frontier of humanity opens up, the upside potentially is practically infinite.

E.g. imagine in a bet you think there's a 99% chance of something being worth $1 and a 1% chance of it being worth $1 million. What's a fair price? It's a simple calculation - 0.99 * 1 + 0.01 * 1,000,000 = ~$10,000. That's you setting a price of $10k on something that you fully expect to be worth $1 99% of the time, and still coming out just fine.

So the actual debate should not be on 'guess the future' but rather on the odds of Starship delivering and estimating the impact this would have. And I think to many the answers are fairly easy - 'very nonzero' and 'very big.' It's akin to the NVidia/Apple stories, except in this case it's being somewhat priced into the market to begin with because it's somewhat more probable, and easier to foresee.

The problem with that argument is the failure to reasonably factor in time. If you take an expected value approach (quite reasonable in general) looking into the future you need to discount for time or everything goes to infinity.

While the point is valid, the upside still isn't practically infinite; humans intuitively do something close to hyperbolic discounting for future returns (I assume evolution did this because of the possibility of black swans but it isn't talking).

The easy version of this is to value a company over the next 20 years of profits. The first half of that time horizon, I don't see much changing at all outside of Starlink subscribers. They've only got ~5 Mars launch windows in any given decade, and while their design philosophy is great for LEO where launch windows are daily, launching rockets to see what fails is exactly wrong for Mars.

OTOH, now to 2036, there's at least a chance AI goes boom. Perhaps even one of Musk's AI. Great for the overall economy (at least right up until it changes the economy so much that capitalism looks as obsolete as feudalism looks today, which may or may not be in that horizon), but even if it's the next industrial revolution, there's so much competition there that I expect everyone's profit margins to be almost nothing. And conversely, if any one of them does appear to be massively dominant, in comes an anti-trust case (who remembers Standard Oil?)

Same with rockets, though a "rocket boom" is perhaps an unfortunate phrasing. He finds a way to make more money than expected, just like he's already doing with Starlink? Great. Industrial espionage is a thing, and even if it wasn't, China's not got a problem with the state funding businesses to simply re-discover everyone else's secret sauce. US companies and residents may find themselves restricted from using the fruit of that work, but most of the world will just buy what's cheapest.

Still, as I said, your point is valid.