Scientists have for the first time discovered a cave on the Moon.
At least 100m deep, it could be an ideal place for humans to build a permanent base, they say.
It is just one in probably hundreds of caves hidden in an “underground, undiscovered world”, according to the researchers.
Countries are racing to establish a permanent human presence on the Moon, but they will need to protect astronauts from radiation, extreme temperatures, and space weather.
Helen Sharman, the first British astronaut to travel to space, told BBC News that the newly-discovered cave looked like a good place for a base, and suggested humans could potentially be living in lunar pits in 20-30 years.
Yes, the moon dust. That incredibly abrasive moon dust. Getting into the workings of the elevator that is your only way out of a deep hole. Any any repair work complicated by having todo it in a suit, in a vacuum, in the moondust, at whatever height it finally broke down
Even rabbits are smart enough to build 2 exits in their tunnels if they’re of any size at all. The weather also isn’t a big deal, so a track that’s been cleaned, and doesn’t have moon dust dragged onto it, shouldn’t need cleaning every other week.