NASA's Kepler Space Telescope Finds Tiny Planet 200 Light-Years Away
Nobody should expect to find anything living on Kepler-37b. The planet orbits its star once every 11 days (Mercury, by contrast, which is scorchingly close to the fires of our sun, takes just under 88 days), so it’s both too small to have an atmosphere and too hot to sustain life even if it had one.
Big planets block more light, little planets block less, and in this case the dimming is so subtle — a little over two-tenths of 1% — that the odds were against Kepler’s noticing at all. “It’s absolutely tiny,” says Thomas Barclay, of the NASA Ames Research Center, lead author of the discovery paper, struggling for the right superlative. Tiny is a relative term when you’re talking about planets, and the diameter of Kepler-37b is in fact about 2,400 miles (3,860 km). But that’s just two-thirds as big as the little planet Mercury and only about 10% bigger than the moon. So yep, tiny fits.