Deep freeze

摘要

Dark, frozen and lifeless-that's the prospect for a planet forming around a brown dwarf star. Yet these inhospitable planets could be very common, the AAS heard.rnBrown dwarfs are tens of times heavier than Jupiter but not massive enough to ignite nuclear fusion, the energy source of stars. Astronomers can't decide whether these mysterious objects are failed stars or super-planets that have escaped the planetary system of their birth. Now observations reported at Pasadena suggest that they have more in common with stars than planets.