Who can blame a failed star for hitching a ride with a success story? The infrared image above shows a newly-discovered brown dwarf that's shadowing Xi
Ursae Majoris, a quadruple star system that is four stars orbiting one another and visible to the naked eye 27 light-years from Earth. The brown dwarf
was born with only a small percentage of our sun's mass, so it failed to fire up its main supply of hydrogen fuel and shine the way larger stars do. But it still glows
from the heat of its formation, emitting infrared radiation that NASA's Wide-Field Infrared Survey Explorer spacecraft has detected. As astronomers
report in work submitted to The Astronomical Journal, the brown dwarf is at least 4100 times farther from the four hydrogen-burning stars than
Earth is from its sun. From the brown dwarf, those four stars are brilliant sights indeed, the two most luminous appearing far brighter than Venus
looks to us—and perhaps provoking a twinge of envy in the star that failed to ignite.
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