According to astronomers, "super Earths" should not exist

NASA's Kepler telescope has now identified an insane 2,326 possible exoplanets. What's particularly shocking is how many of these planets are giant rocky planets known as Super-Earths, which defies everything we thought we knew about planet formation. » 12/19/11 9:30am 12/19/11 9:30am

Why Earth might have started out as a gas giant

All planets are vast clumps of dust and gas packed together by gravity. If there's lots of material, a gas giant is the result. If there isn't much material, you get a rocky planet. At least, that's what we thought. » 9/18/11 11:20am 9/18/11 11:20am