Some scientists think spreading clouds of moon dust between Earth and the sun could help us defeat global warming.
The idea is that moon dust would reflect the sun's heat away from Earth.
Ideas for blocking the sun's radiation, to keep the Earth from overheating, have been going around for decades. The theory works, because when a volcano erupts and throws large amounts of dust into the atmosphere, the world's temperature goes down.
Blocking just one-hundredth of the sun's rays would lower Earth's temperature by one or two degrees. That is about how much it has warmed up over the last 100 years.
The scientists want to use moon dust because nobody else needs it.
