Luhman and his colleagues used the Hubble Space Telescope to photograph an object, about 10 Jupiter masses, orbiting the star CHXR 73. The orbiting object's mass alone would typically identify it as a heavy planet spawned from a disk that once surrounded this young star. However, the newfound object lies about five times as far from CHXR 73 as Pluto's average distance from the sun. Theory suggests that a gas-and-dust disk isn't likely to contain enough material that far from a star to make a planet... Distinguishing between brown dwarfs and planets is important, says Luhman. A brown dwarf could...