Science / Medicine : Brown Dwarfs Believed Found

University of Minnesota astronomers believe they have found brown dwarfs--gaseous celestial bodies that failed to reach stardom--hiding in the heavens and, more important, some of the universe’s missing mass.

Armed with a special computerized scanner developed in the 1960s, an astronomy team last fall found a dozen objects the researchers believe are brown dwarfs sprinkled among stars in a cluster 150 light years from Earth. “I know we’ve found them; I’m 90% certain,” astronomer Roberta Humphreys said last week at a meeting of the American Astronautical Society in Atlanta.

The brown dwarf theory originated years ago when scientists studying the gravitation that holds the universe together calculated that 90% of the mass required to generate the awesome forces could not be accounted for. Some of the “missing” mass, they figured, probably was hidden in huge blobs of gaseous matter floating around the universe. Eventually dubbed brown dwarfs, each of these gas blobs had to have more mass than Jupiter, the largest planet in the solar system, but less mass than a real star, which must be 80 times more massive than Jupiter to sustain nuclear fusion.