Two new brown dwarfs have been discovered relatively close to to our solar system. Spotted by astronomers from the Leibniz Institute for Astrophysics Potsdam (AIP), the "failed stars"* are only 15 and 18 light-years from the sun.
15 and 18 light-years may not seem that close -- after all, the nearest bona fide star to the sun, red dwarf Proxima Centauri, is a mere four light-years away. But if these discoveries continue it may not be long until a brown dwarf, and not Proxima, is found to be our nearest stellar neighbor.
ANALYSIS: Record Breaker: 'Very Cold' Brown Dwarf Discovered
These two brown dwarfs, called WISE J0254+0223 and WISE J1741+2553, are in addition to the AIP team's 2003 discovery of another two brown dwarfs orbiting the star Epsilon Indi, 12 light-years from Earth. This new double discovery was made during analysis of recently published data from NASA's Wide-field Infrared Survey Explorer (WISE).
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The new objects, radiating brightly in infrared wavelengths, grabbed the team's attention as both are moving at high speed across the sky -- this was an indication that they may be fairly close to us. Later, their close vicinity was confirmed after comparing their color and magnitude with other known brown dwarfs.
ANALYSIS: Ultra-Cold Brown Dwarf Discovered?
Brown dwarfs are often referred to as "failed stars" as they are not massive enough to support nuclear fusion in their cores, and yet they cannot be called "planets" as they don't exhibit chemical differentiation with depth and have convective flows -- a very star-like quality. Therefore, they exist in a stellar hinterland, where they are neither a star or a planet, and yet exhibit characteristics of both.
But astronomers still classify brown dwarfs by their spectral type (a scale of letters assigned to the luminosity of stars), which relates to their temperature. At the lowest, coolest end of the scale, radiating in infrared wavelengths, are the oddball brown dwarfs.
Read More: http://news.discovery.com/space/could-ultracool-brown-dwarfs-surround-us-110718.html
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