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Comment by bitxbitxbitcoin | Hacker News Reader

For 1., there's really no way to know is there? The best analogy I can think of is all the precious metals from the New World and how their discovery and subsequent introduction to the Old World in the 16th century and on effected the economies there.

For 2., I think there's a good case to be made for a lot of that metal staying up in space as opposed to dropped and then launched back up eventually. In the long long term, isn't it reasonable to assume that Earth may end up losing mass due to space launches? Here's my corollary to your question for whoever comes along to answer: Is it possible that lessening mass could speed us up?

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> In the long long term, isn't it reasonable to assume that Earth may end up losing mass due to space launches?

Earth masses 6e24 kg. SpaceX Starship can carry 1e5 kg. Suppose a MILLION fully loaded Starships launched EVERY SECOND, starting now.

It would take 20000 years of that for earth to lose 1% of its mass.

>In the long long term, isn't it reasonable to assume that Earth may end up losing mass due to space launches?

No. It is much more likely that Earth would become a long-term importer of space manufacturing for quite some time. It is much cheaper to drop stuff down into Earth's deep gravity well than to hoist it up into space. Pretty much everything in orbit (except for the Moon and mass where the Moon's gravitional influence dominates) will eventually come back down to the Earth's surface, too

It's not 'harder' to take mass off earth than it is to bring mass back. Assuming you want to bring the mass back 'gently' and not have it collide with earth like a comet. Think like pulling a rock out of a hole vs lowering it back down in a controlled manner, controlled here meaning velocity=0 by the time it reaches the bottom. In both cases you are responsible for transitioning the same amount of energy into or out of the rock. To do this with a rocket would required the same integration of force and thus fuel. In the case where you are lowering the rock, ie returning mass back to space, you have to bring fuel to the rock to 'lower' it back down so it is actually harder to bring mass back.

Even for uncontrolled crashing you still need to use fuel. You need to use energy to slow the object down enough to fall into earths gravity well.

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