4 min read<\/p>\n
NASA\u2019s Hubble Finds that Aging Brown Dwarfs Grow Lonely<\/h1>\n<\/div>\n<\/div>\n<\/div>\n
It takes two to tango, but in the case of brown dwarfs that were once paired as binary systems, that relationship doesn\u2019t last for very long, according to a recent survey from NASA\u2019s Hubble Space Telescope<\/a>.<\/p>\n Brown dwarfs are interstellar objects larger than Jupiter but smaller than the lowest-mass stars. They are born like stars \u2013 out of a cloud of gas and dust that collapses \u2013 but do not have enough mass to sustain the fusion of hydrogen like a normal star.<\/p>\n The name \u201cbrown dwarf\u201d is a misnomer because the object would typically appear red to the naked eye. It is brightest in infrared light. Many brown dwarfs have binary companions. But as they age, the binary system gravitationally falls apart, and each dwarf goes its separate way, according to a recent Hubble Space Telescope study.<\/p>\n The background stars in this illustration are a science visualization assembled from the Gaia spacecraft star catalog. The synthesized stars are accurate in terms of position, brightness, and color. Because this is not an image of the Milky Way, missing are glowing nebulae and dark dust clouds.<\/p>\n<\/div>\n Astronomers using Hubble confirm that companions are extremely rare around the lowest-mass and coldest brown dwarfs. Hubble can detect binaries as close to each other as a 300-million-mile separation \u2013 the approximate separation between our Sun and the asteroid belt. But they didn\u2019t find any binary pairs in a sample of \u00a0brown dwarfs in the solar neighborhood. This implies that a binary pair of dwarfs is so weakly linked by gravity that they drift apart over a few hundred million years due to the pull of bypassing stars.<\/p>\n \u201cOur survey confirms that widely separated companions are extremely rare among the lowest-mass and coldest isolated brown dwarfs, even though binary brown dwarfs are observed at younger ages. This suggests that such systems do not survive over time,\u201d said lead author\u00a0Cl\u00e9mence Fontanive<\/a>\u00a0of the Trottier Institute for Research on Exoplanets, Universit\u00e9 de Montr\u00e9al, Canada.<\/p>\n In a similar survey Fontanive conducted a couple of years ago, Hubble looked at extremely young brown dwarfs and some had binary companions, confirming that star-forming mechanisms do produce binary pairs among low-mass brown dwarfs. The lack of binary companions for older brown dwarfs suggests that some may have started out as binaries, but parted ways over time.<\/p>\n![\"\"](\"https:\/\/science.nasa.gov\/wp-content\/uploads\/2024\/03\/hubble-brown-dwarf-illustration-stsci-01hqtgma3t0e0fmag6kd1d053k.jpg?w=2048\")
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