Astronomers have discovered a brown dwarf that is more than 99 % hydrogen and helium. Artist’s impression shows BD+01 2920B in the foreground, on the right hand side, with its host star in the background. The color and banded atmosphere of the brown dwarf result from atmospheric gases and turbulence (J. Pinfield / RoPACS network / University of Hertfordshire) This brown dwarf, described in the Monthly Notices of the Royal Astronomical Society,...
