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Black star

  1. Mar 9, 2010 #1
    Is there such a thing as a black star? Not black hole.

    I read something from a national geographic magazine a few months back that was about an astronomical object. It was all black on the outside, emitted darkness instead of light, and it contained some water. It was some new discovery or something. I may have got some of it wrong, it was a while ago and I can't remember much. Maybe it was a hypothesis :S

    If anybody knows what I'm talking about or clear any of this up, that would be great :)
    Last edited: Mar 9, 2010
  2. jcsd
  3. Mar 9, 2010 #2


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    Sure, there are gazillions of them - objects not sufficiently massive to trigger hydrogen fusion in their cores. Jupiter is one example.
  4. Mar 20, 2010 #3
    Black star was an early name for black holes...the latter coined by John Wheeler I believe.
  5. Mar 20, 2010 #4


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    This doesn't make sense. How could something emit the absence of something? Either you misunderstood the article, or it was written by someone who knows nothing about this kind of thing! As Chronos notes, there are many large objects which are large starlike balls of gas which do not shine under fusion, although they are typically referred to as brown dwarfs. And they do radiate, just like any other black body, so they certainly are not black!

    Could you give a reference if you have one? I'd like to see this absurd claim!
  6. Mar 20, 2010 #5


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    Also, a black dwarf is the name given a remnant of a white dwarf after it has cooled sufficiently. However, the Universe is not old enough for any black dwarfs to have formed yet.
  7. Mar 23, 2010 #6
    From wiki-

    http://en.wikipedia.org/wiki/Black_Star_(semiclassical_gravity [Broken])
    Last edited by a moderator: May 4, 2017
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