Second Most Earth-Like Planet to Date Found

[stevebowers]

I don't think that a super-selenian is necessarily the most likely case, since there would probably be some core material present. A more likely case is a planet with an iron core and a smaller radius at the rocky surface covered by a thick hydrosphere and/or atmosphere to fill the planet out to the observed radius.

Alternately it could be a carbon planet; these are dry, so no hydrosphere would be present but with a minimal iron core you could get the same density. So there are lots of possibilities that fill the smallest mass case. Life might be possible on a carbon planet, but it would not not very similar to Earth-life.