Astronomers Find Another Small Icy Body Out Past Pluto

Astronomers have found an interesting new world orbiting the Sun -- no, it's not Planet Nine, but it's still cool. Called 2015 KH162, it's a small(ish) object orbiting the Sun far, far past Pluto. It's not clear how big it is. You can figure out an object's size if you know how far away it is (which we do) and how reflective it is, a number called its albedo. If it's shiny it can be small and still look bright; if it's dark it has to be much bigger to appear as bright. Albedos can be difficult ...