Just 13 parsecs away, a planet astronomers are calling a "super Earth" is orbiting a dwarf star. Its radius is over twice that of Earth, and there's something very surprising in its core.


Known by the designation GJ1214b, this planet is, according to a paper published yesterday in Nature, one of just two super Earths found recently. It has "a composition of primarily water enshrouded by a hydrogen–helium envelope," and its atmosphere has evolved a great deal over time (much like Earth's). Unlike another super Earth discovered recently, CoRoT-7b, this new super Earth has an atmosphere that can be studied fairly easily due to the size of its star and close proximity.

What's most intriguing is that this super Earth appears to be made up of possibly 75 percent water. Unlike Earth, which has a molten rock and metal core, GJ1214b probably has a core made of water too. (Those of you who read Iain M. Banks' novel The Algebraist are probably grinning right now.) Astronomers aren't entirely certain that the planet is water - this is just an educated guess based the planet's density, which was calculated by observing how much the red dwarf dimmed when this planet passed in front of it.


Given its distance from the dwarf, GJ1214b's surface temperature could be as much as 530 degrees Fahrenheit. On Earth, water at that temperature would boil off into steam. So it's likely that something about GJ1214b's atmosphere is keeping its oceans in an ultrahot liquid state. Basically, we've got a giant boiling ball of water - the perfect place to breed weird new life.

via Nature