Water is rocket fuel.

BBC: What if you could mine the Moon?

Oxygen could be derived from ilmanite reserves there and water could be extracted to make rocket fuel or sustain life on a base.

CNN: Mining the moon for a nuclear future

The oxygen that remains is burned with fuel and water in a chamber modeled after a rocket engine.

FORBES

But some are also thought to harbour water ice, which could be used as a raw material for the manufacture of rocket propellant or even breathable air.

BBC: New venture 'to mine asteroids'

Water from asteroids could be broken down in space to liquid oxygen and liquid hydrogen for rocket fuel.

BBC: Plans for asteroid mining emerge

In this way, things like rocket engines, satellites, Mars-exploring rovers, space suits, and water purifiers on the International Space Station become part of everyday life on Earth.

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My favorite example of this environmental excess is the ground water cleanup efforts around Sacramento, California, where one aerospace company has managed to reduce the incidence of rocket-fuel ingredient perchlorate to four parts per billion.

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Further, study of the captured space rock could teach researchers how to efficiently extract water from asteroids a resource that could be an off-Earth source of radiation shielding and rocket fuel for journeying spacecraft.

MSN: NASA might lasso an asteroid and drag it to orbit near moon