Brown dwarf. Artwork of a planet-like brown dwarf \star\" on the edge of a globular cluster of stars, seen from a nearby moon. Brown dwarves may form

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Brown dwarf. Artwork of a planet-like brown dwarf \star\" on the edge of a globular cluster of stars, seen from a nearby moon. Brown dwarves may form part of dark matter, the invisible material that makes up about 90% of the universe's mass. Brown dwarves are classed as MACHOs (Massive Compact Halo Objects) because they are likely to have formed on the periphery (halo) of a galaxy where material is scarce. A brown dwarf is an object which began to accumulate material like a star but which never collected enough for nuclear reactions to begin in its core. Brown dwarves are difficult to detect because, like a planet, they can only be seen by the light they reflect from nearby stars."

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Size: 4705px × 3716px
Photo credit: © JOE TUCCIARONE/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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