The First Carbon Planet?
So you think you live on a carbon-rich planet? Silly Earthling! Although terrestrial life is based on carbon, the element makes up precious little of the Earth’s crust. Instead, oxygen - locked in silicate rocks - constitutes nearly half of the surface beneath your feet. Now astronomers have found a planet they say really is carbon-rich. Reporting online today in Nature, they say it circles a sunlike star named WASP 12 in the constellation Auriga, roughly 800 light-years away. The world is a gas giant like Jupiter that orbits so close to its star that it sizzles at thousands of degrees. By studying the planet’s infrared glow, the astronomers discovered that its air abounds with the carbon-bearing molecules carbon monoxide and methane, implying that the planet could have carbide (a compound of carbon and metal) rather than silicate in its interior. If so, that makes it unlike any world in our solar system.