Cygnus X-1, Stellar Black Hole, Wide Field

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Cygnus X-1 is a black hole about 15 times the mass of the Sun in orbit with a massive blue companion star. Using optical observations of the companion star and its motion around its unseen companion, the team made the most precise determination ever for the mass of Cygnus X-1, of times the mass of the Sun. It was likely to have been almost this massive at birth, because of lack of time for it to grow appreciably. Release date November 17, 2011.

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Size: 3544px × 3600px
Photo credit: © Photo Researchers / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -1, -ray, 2011, 21st, astronomical, astronomy, black, body, celestial, century, cosmography, cosmological, cosmology, cosmos, cyg, cygnus, deep, event, evolution, field, galactic, heavenly, hole, horizon, image, mass, object, optical, point, return, science, sky, source, space, stellar, stellar-mass, universe, wide