Astronomers have discovered a possibly Earth-like—and therefore possibly liveable—planet in a star system 20 light years away, which is pretty close, in galactic terms. But can we all move to that planet when we've finished destroying this one?
The planet, located in the Gliese 581 star system (that's an artist's representation above, courtesy the European Southern Observatory), is in the so-called "Goldilocks zone" that can support liquid water—not too hot, not too cold, filled with a center of molten porridge. It's about three times the size of earth, and orbits a small red dwarf some 120 trillion miles away. Sounds awesome, right? And my lease is up in November!
But, as Bad Astronomy's Phil Plait points out, there are some problems with the planet that may make it inhabitable. Its days are the same length as its years (37 Earth days), and the same side of the planet is always facing the sun (the way the moon is always facing the same way towards us), which is a huge bummer, unless you are a vampire, or afraid of the dark.
If the planet has an atmosphere, it could mitigate the fact that the sunny side will always be hot and the dark side always cold. But it might not have an atmosphere at all. Nonetheless, Plait is excited:
The fact that we found a planet that is even anything like the Earth at all orbiting another star only 20 light years away makes me extremely optimistic that earthlike planets are everywhere in our galaxy. 20 light years is practically in our lap compared to the vast size of our galaxy, so statistically speaking, it seems very likely it's not unique.