Link to full articleBrown dwarf-hunting astronomers have reported the discovery of a "failed star" located within 10 light-years from Earth. This makes it the nearest brown dwarf and one of ten nearest stellar objects to our solar system. Although its location isn't entirely unexpected (it is thought that the galaxy is stuffed full of these objects), the chemical composition of its atmosphere is a bit of a conundrum.
How close could such a dwarf be without having been detected already?