Companies want to mine asteroids for fuel, and build filling stations in space. A bill in front of Congress would help by allowing them to own what they discover, but it might meet stiff international opposition. it costs nearly $2bn per year to launch enough water to sustain the six astronauts aboard the International Space Station.
In addition to providing drinking water, H20 can also be converted into breathable air, and into fuel, liquid hydrogen and oxygen form the most efficient rocket fuel known to man. Currently, spacecraft must carry all the fuel they require, adding significant weight and driving up the cost of getting beyond Earth’s gravity. Once in space, expensive equipment may be abandoned because it’s too costly to take back to Earth. But, says Lewicki, "Imagine being able to get into space and refuel your spaceship [there]."
Asteroids have little gravity, he adds, so landing on and taking off from them does not require too much energy. Their prevalence and proximity to Earth make them valuable potential way stations for refuelling on longer missions into space.