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Planet Or Failed Star? NASA's Hubble Telescope Photographs One of Smallest Stellar Companions Ever Seen


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Astronomers using NASA's Hubble Space Telescope have photographed one of the smallest objects ever seen around a normal star beyond our Sun. Weighing in at 12 times the mass of Jupiter, the object is small enough to be a planet. The conundrum is that it's also large enough to be a brown dwarf, a failed star. The Hubble observation of the diminutive companion to the low-mass red dwarf star CHXR 73 is a dramatic reminder that astronomers do not have a consensus in deciding which objects orbiting other stars are truly planets -- even though they have at last agreed on how they will apply the definition of "planet" to objects inside our solar system.

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      Corinne Beckinger
      Marshall Space Flight Center, Huntsville, Alabama
      256-544-0034
      corinne.m.beckinger@nasa.gov
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