On Earth, lava tubes are about 10 meters wide and stretch for a good mile or so. But on the moon, because of the lower gravity, they could be hundreds of meters wide. They form these enormous networks that can run for hundreds of kilometers,. Hundreds of miles across the moon's surface. In theory, there would be enough space in there for us to create a settlement.
The visit of Xi Jinping, China’s president, to Moscow may seem like the solidifying of a simple, anti-Western alliance. But China is walking a delicate line to look after its own interests. A growing minority of young people simply do not want to drive; that will have consequences far beyond roadways. And research on colonising the Moon goes underground.
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