How can it be “geology” when that term is specific to planet Earth?
A major part of the cost of mining on earth is due to the amount of material that needs to be mined for comparatively small amounts of metal. Then there are environmental issues that need to be dealt with.
The crust of the earth contains something like 15% iron while some asteroids are believed to be as much as 70% iron or more. Plus they don’t have the environmental issues to worry about.
Mining and refining metals in space would likely lead to some major leaps in space travel because we’re pretty limited in what we can lift from the surface of the earth. Combine it with ever expanding printing technology we could see aircraft carrier sized ships with large crews within 100 years.
We will have to get an elevator going. Re-entry of all that metal will destroy half it and no telling what would happen if they lost control of it.
if we can land on a comet...
We need to figure out how to ‘mine’ the space debris in orbit around the Earth.
Just go to Sudbury, Canada. There is a huge meteor that landed there that not only provides iron ore but all kinds of other metals that resulted from the flow of magma from the meteor hit.
I suggest using rockets to maneuver an asteroid to land on Earth, somewhere around Iran. What the heck the whole mid east....
It sounds pretty ridiculous on second glance too.
It is true that water exists in many asteroids, but it is chemically bound in clay minerals. Only cometary cores contain free water ice -- they are abundant in the outer solar system (hard to get to) and those in the inner solar system travel at very high speeds (difficult to intercept). Breaking the chemical bounds to get at asteroid water is very energy intensive. You cannot simply heat the material using solar thermal -- you would just get hot asteroid. Thermal breakdown of the clay will occur at very high temperatures, but the released water will react with other components in the asteroid giving you new hydrous compounds, not free water.
As for metals, the problem is that they are alloyed with iron-nickel, so you would have to smelt the material, again extremely energy intensive. But suppose that you did smelt it -- you need some process to extract and separate the metals. No gravity, so no convection and no density settling. You could spin your processing module to create artificial gravity, but again, it requires bigger, heavier and more complex spacecraft.
Energy is the real show-stopper. You need tens to hundreds of megawatts to process at industrial scales. Difficult to do with simple solar arrays (the arrays on the space station only generate about 100 kw total). You are almost driven to a nuclear reactor for power. Trouble is, a space nuke of that size does not exist - and you would need billions to develop one.
The idea that asteroids are full of valuable products is the same concept as saying that seawater contains tons of gold. True -- but so what?