Not all stars are hot. Astronomers have discovered a brown dwarf — a class of very feeble stars — in our stellar neighborhood that is between -48 to -13 degrees Celsius. The brown dwarf, the coldest one known, is just 7.2 light-years away, making it the fourth closest star to our sun.
Brown dwarfs straddle the line between stars and planets. They can help astronomers learn more about not only the evolution of stars but also the atmospheres of gas giants like Jupiter.