| famousringo said: Can somebody explain to me how this planet could have six times the Earth's mass and yet less gravity? Is it a matter of density and how far into the atmosphere you have to travel before you reach the surface? Edit: Maybe they're figuring in displacement as if you didn't have to visit the planet inside a sturdy pressure hull? |
Here is the explanation:
The CoRoT-7b has a density close to that of the Earth (5.5 grammes per cubic centimetre) and seems to be rocky, while the new discovery appears to be much less dense (1.9 g/cm3).
"To keep the planet's density that low requires that it contains large amounts of water," said Marcy. "It must contain a huge amount of water, roughly 50 percent by mass."
There you go.
http://news.yahoo.com/s/afp/20091216/sc_afp/scienceastronomy
I guess that is why its even considered for being an ocean planet.
Back from the dead, I'm afraid.
