• Pollux Pollux is a star in Gemini. # ############### ##################### ######################### ########################### ############################# ############################### ############################### ################################# ############################### ############################### ############################# ########################### ######################### ##################### ############### # Type Orange supergiant Constellation Gemini Magnitude 1.1 Spectral type K0IIIb Distance 34 light years Double star components 201.1″ apart You need naked eye from a dark sky Known as Bayer β Gem Yale HR 2990 More information about Pollux Pollux is one of the two heads of Gemini, the twins, and at 34 light years it is the closest giant star to the Sun: a star that has finished burning hydrogen in its core, swollen up and turned orange. A planet several times the mass of Jupiter orbits it. It is brighter than Castor beside it, and the labelling never caught up: Castor was lettered Alpha Geminorum and Pollux only Beta, though the letters were meant to run from the brightest star down. Bayer lettered the stars of each constellation in his Uranometria of 1603, in order of brightness. He was working from Tycho's magnitudes by eye, and the order he recorded is often wrong. First published in 1930 by Yale astronomer Frank Schlesinger, and maintained since, the Yale Bright Star Catalogue lists every star down to magnitude 6.5. It contains 9,110 stars. where it is tonight: skymap.sh/Pollux