This artist's illustration shows a brown dwarf with a disk of planet-forming material around it. Brown dwarfs are bodies without enough mass to ignite nuclear fusion and become stars.
NASA's Spitzer Space Telescope could be used to find Mars-size alien planets orbiting strange "failed stars" known as brown dwarfs, according to a new proposal by a multinational astronomy team.
The group, led by a postdoctoral researcher at MIT, proposes to use the venerable observatory to find small, rocky exoplanets around brown dwarfs, which are larger than planets but too small to ignite the nuclear fusion reactions that power stars.
Astronomers will seek planets crossing the face of these brown dwarfs, in the hopes that some of them will end up being capable of supporting life as we know it. [9 Exoplanets That Could Host Alien Life]
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