A Rock Of Unusual Size

A Rock Of Unusual Size

It seems that whenever we have a fact about exoplanets nailed down, an exception will quickly crop up. The authors of today’s paper claim to have spotted a planet over twice the diameter of the Earth, made from solid rock.

Planet IX

Planet IX

Get ready to come up with a new mnemonic for the planets. The orbits of distant objects suggest that there may be something lurking in the outer Solar System as big as Neptune!