Radically Rethinking
2nd October 2009, 04:40 PM
I'm always fascinated by news of exoplanets. Here's the latest on COROT-7b, the first confirmed exoplanet with a rocky surface:
Because the planet is so close to the star, it is gravitationally locked to it in the same way the Moon is locked to Earth. One side of the planet always faces its star, just as one side of the Moon always faces Earth.
This star-facing side has a temperature of about 4,220 degrees Fahrenheit (2,326 degrees Celsius) — hot enough to vaporize rock.
So unlike the much cooler Earth, COROT-7b has no volatile gases (carbon dioxide, water vapor, nitrogen) in its atmosphere. Instead it's atmosphere consists of what might be called vaporized rock.
...
"Sodium, potassium, silicon monoxide and then oxygen — either atomic or molecular oxygen — make up most of the atmosphere," Fegley said. But there are also smaller amounts of the other elements found in silicate rock, such as magnesium, aluminum, calcium and iron.
Because the planet is so close to the star, it is gravitationally locked to it in the same way the Moon is locked to Earth. One side of the planet always faces its star, just as one side of the Moon always faces Earth.
This star-facing side has a temperature of about 4,220 degrees Fahrenheit (2,326 degrees Celsius) — hot enough to vaporize rock.
So unlike the much cooler Earth, COROT-7b has no volatile gases (carbon dioxide, water vapor, nitrogen) in its atmosphere. Instead it's atmosphere consists of what might be called vaporized rock.
...
"Sodium, potassium, silicon monoxide and then oxygen — either atomic or molecular oxygen — make up most of the atmosphere," Fegley said. But there are also smaller amounts of the other elements found in silicate rock, such as magnesium, aluminum, calcium and iron.