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Comment by martyvis | Hacker News Reader

I think they have a "build it and they will come" attitude. While their own Mars goals will need 100s if not 1000s of launches they also see new customers that would want launch and even recover much larger payloads than what are feasible today

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I think that's a reasonable attitude to a point, but like, it doesn't scale infinitely. Build it and it will come to 50-100x today's launch capacity? And Mars is still a laughable pipedream. Doing 100s of launches will cost SpaceX so much more than they are making selling launches to the rest of the world, it simply makes no sense.

And like, I'm a space enthusiast. I think we should be out mining asteroids and setting up space living quarters. I just... hourly starship launches don't make any sort of logical sense.

What they do make sense as is a marketing gimmick for Elon to get on stage to appeal to emotions of investors and nerds online. It's a gorgeous dream! I want it to be! But it's just a clever emotional appeal to get you to not think too hard or too critically.

The asteroid belt is even further than Mars so you need rapid reusability for that too.

The asteroid belt doesn't have nearly the gravity well to send payloads back from, but it seems much harder to make propellant there in situ.

You don't need to go to the asteroid belt to get to meaningful asteroids, and in fact many fantastic candidate asteroids come much, much closer than Mars.

They don’t come as close as LEO though so you still need rapid reusability.

> Build it and it will come to 50-100x today's launch capacity

Yes, because Starship promises 50-100 times cheaper delivery of kg to LEO.

Read https://caseyhandmer.wordpress.com/2021/10/28/starship-is-st... on the subject.

Let's take the pessimistic estimates of Falcon 9 Heavy, which are about $3000/kg to LEO. (The optimistic estimates put it closer to $1500.)

You are suggesting that pessimistically, Starship is aiming at $30-60/kg to LEO. (Or, using the optimistic estimates, $15-$30/kg to LEO).

I don't think in even Elon Musk's wildly optimistic press conferences he pushed a number below ~$100/kg to LEO. I don't know where you get the idea that launch costs are going to come down 50-100x.

Back-of-the-envelope calculations look like this: fully reusable Starship's flight costs roughly the cost of fuel, which is 1-2 million dollars per flight, both stages. If the Starship carries 150 tons to orbit per flight, and it costs $1.5e6, then we have the price of 1 kg on orbit equal to $1.5e6 / 150e3 = $10. Which is rather comfortably 100 times cheaper than SOTA.

Wildly optimistic would seem to be even lower estimations. If both oxygen and methane we can get from atmosphere - and we have both efficient detanders and demonstrations of e.g. Terraform Industries which use solar panels and oxygen to pull CO2 from atmosphere and produce CH4 - then the question is of optimization, and we're just starting here for this application. So, a flight of Starship might get cheaper than $1 million - the question is, how much and how soon?

I haven't seen anywhere suggesting a $1-2m launch cost is a reasonable target. Sure, maybe $10m is achievable, but $1m is so far off it's not useful as a cost estimate.

I think it's just you didn't see such estimates. Here's what I found first. https://www.space.com/spacex-starship-flight-passenger-cost-...

It depends on what you are thinking critically about - what is your frame of mind. You don't see a viable business here.

But SpaceX does see several possibilities. One is supplying a US Moon base and US space stations. Since Starship/Superheavy rockets are so inexpensive to build (about 100M in expendable configuration [1] even doing something like that would be profitable for SpaceX.

For Mars colonization, Elon Musk has said his target for Starship to Mars cost per flight was USD 10M. If it can take 100 people, and they each pay USD 200K per person, that's USD 20M, a 10M profit for SpaceX.

It might also be that a nation state might want to fund something like that to establish a base there.

Again, you may see a viable business in Mars colonization. But SpaceX does. So do other people. It was conventional wisdom that Starlink would not work, but it is now quite profitable. [2]

[1] https://en.wikipedia.org/wiki/SpaceX_Starship

[2] https://www.nasdaq.com/articles/billionaire-elon-musks-new-s...

> For Mars colonization, Elon Musk has said his target for Starship to Mars cost per flight was USD 10M. If it can take 100 people, and they each pay USD 200K per person, that's USD 20M, a 10M profit for SpaceX.

Musk has lied many times about many things. This one in particular makes less than 0 sense - Starship has nowhere near the capacity to take 100 humans to Mars even just including the provisions needed for the trip, unless you assume that those people will essentially sit in their own little cell for 2 months.

Thank you. I was timed out, but I was going to say there's 0% chance of Starship taking 100 people. Do you have any concept of how much water, oxygen, C02 scrubbing, food, shielding, medicine, and infrastructure you need to support 100 people?! Imagine the device they have on the ISS, multiply it by 20, and then pack all the water it uses in a year in advance onto the ship. Then pack 100 warm bodies in there too?

It's simply not possible in the ship they've designed.

You seemingly ignored the cost of the return ticket, which even with your fantasy numbers would cost many millions of dollars.

Cramming one hundred people into a starship is eerily reminiscent of overloaded slave ships. The assumption is that you will die on the journey or at your destination.

They don't really plan for people coming back from Mars, for most of them its a one way ticket...

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