The 8-Hour Planet

There are plenty of factors that go into whether a planet could sustain life, but the real secret may be its rotation. Earth is strangely perfect for the life it has, because its rotation gives us sunshine, but not too much of it. It also gives us weather. Planets that spin slower or faster, depending on the planet's mass, make life difficult, or more likely, impossible.

Astronomers have figured out some really complicated ways to figure out how fast exoplanets spin, if they do. Calculations like this may lead us to places outside our solar system that could sustain life in one form or another. Or if we don't, maybe we can gain more appreciation for the unique planet we have.