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This is potentially the most important discovery in planetary science to date. The reason, which is left until the end of this article, is that water can be ele

This is potentially the most important discovery in planetary science to date. The reason, which is left until the end of this article, is that water can be electrolyzed to yield hydrolox propellant, i.e. rocket fuel. Rocket fuel dominates logistics in space. The tyranny of the rocket equation is that it takes an exponential (literally exponential, not in the colloquial sense) amount of fuel for a linear increase in velocity. This is why it's so hard to go to Mars, and why we need to slingshot around Jupiter to go anywhere else. A source of rocket fuel above Earth's gravity well would break the tyranny of the rocket equation, and serve as a stepping stone to other parts of the solar system where water is abundant (i.e. Ceres, Mars). Until we have nuclear or other exotic propulsion, water is the oil of space. To paraphrase the lunar anthropic principle, if the universe had wanted humanity to become a spacefaring species, it would have given us a Moon, and it would have put water on it. We're just scratching the surface of what these lunar water deposits mean.

Aperocky 6y ago
Either more fuel or patience, and I think patience is going to win. There are interplanetary 'highways' where you can spend barely any deltaV to go everywhere, provided you have patience. Probes are already transiting Earth and Venus multiple time to get slingshots to outer solar system. The ideal space base is a manufacturing hub in the asteroid belt. Where deltaV to go to anywhere else is ~0 and deltaV to launch stuff from base is also ~0. That's the only way to have star wars sized ship. Launching one from gravity well of the Earth or even Moon is just lunacy.
PaulHoule 6y ago
I see it the other way around. Earthers find it hard to kick the idea that hydrogen and hydrocarbons are fuels, but that is because oxygen is free on the surface of the Earth. On Luna you might use that hydrogen to reduce hematite ore (found in commercial quantity by astronauts) to Iron and Oxygen. Oxygen is like 7/8 the mass of the fuel you need, you can make storage tanks, residential neighborhoods, whatever you want out of steel if you can find a small amount of carbon. You can recycle the hydrogen, it's not lost as it would be if you burned it. Lunar oxygen mining to refuel something like the SpaceX Starship faces tough competition from Earth via the SpaceX Starship -- a 1990s study looked at 5 Earth to Mars mission scenarios with and without lunar materials and it wasn't clear you could win with lunar oxygen. The moon is close in configuration space to the Earth but far away in phase space (including energy differences) NASA figured Apollo hardware could make it to Venus https://en.wikipedia.org/wiki/Manned_Venus_flyby https://en.wikipedia.org/wiki/Manned_Venus_flyby because you can use resonances around the moon to get a kick away from the Earth as opposed to fighting the gravity well with a low-ISP rocket on the way up and down from La Luna (no, atmospheric reentry on Earth is not "a problem" but rather free delta-V and one hell of a preimage for your landing site) A good main belt asteroid might be like Saudi Arabia but with the relative proportions of sand and hydrocarbons reversed. You would be looking at a solar 5km/sec mission unless we got lucky and found a medium rare asteroid in the "near earth" area. Either way if you could build a chemical factory that can make things like Kapton, Mylar or sheet graphene it shouldn't be that hard to handle giant films to make a solar sail factory, install sunshades at L1, beam solar power to moon bases at night, etc.

Aperocky 6y ago

Either more fuel or patience, and I think patience is going to win. There are interplanetary 'highways' where you can spend barely any deltaV to go everywhere, provided you have patience. Probes are already transiting Earth and Venus multiple time to get slingshots to outer solar system. The ideal space base is a manufacturing hub in the asteroid belt. Where deltaV to go to anywhere else is ~0 and deltaV to launch stuff from base is also ~0. That's the only way to have star wars sized ship. Launching one from gravity well of the Earth or even Moon is just lunacy.

PaulHoule 6y ago

I see it the other way around. Earthers find it hard to kick the idea that hydrogen and hydrocarbons are fuels, but that is because oxygen is free on the surface of the Earth. On Luna you might use that hydrogen to reduce hematite ore (found in commercial quantity by astronauts) to Iron and Oxygen. Oxygen is like 7/8 the mass of the fuel you need, you can make storage tanks, residential neighborhoods, whatever you want out of steel if you can find a small amount of carbon. You can recycle the hydrogen, it's not lost as it would be if you burned it. Lunar oxygen mining to refuel something like the SpaceX Starship faces tough competition from Earth via the SpaceX Starship -- a 1990s study looked at 5 Earth to Mars mission scenarios with and without lunar materials and it wasn't clear you could win with lunar oxygen. The moon is close in configuration space to the Earth but far away in phase space (including energy differences) NASA figured Apollo hardware could make it to Venus https://en.wikipedia.org/wiki/Manned_Venus_flyby https://en.wikipedia.org/wiki/Manned_Venus_flyby because you can use resonances around the moon to get a kick away from the Earth as opposed to fighting the gravity well with a low-ISP rocket on the way up and down from La Luna (no, atmospheric reentry on Earth is not "a problem" but rather free delta-V and one hell of a preimage for your landing site) A good main belt asteroid might be like Saudi Arabia but with the relative proportions of sand and hydrocarbons reversed. You would be looking at a solar 5km/sec mission unless we got lucky and found a medium rare asteroid in the "near earth" area. Either way if you could build a chemical factory that can make things like Kapton, Mylar or sheet graphene it shouldn't be that hard to handle giant films to make a solar sail factory, install sunshades at L1, beam solar power to moon bases at night, etc.