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Astronomers Solve the Mystery of 'Hanny's Voorwerp'

KentuckyFC writes "In 2007, a Dutch school teacher named Hanny van Arkel discovered a huge blob of green-glowing gas while combing though images to classify galaxies. Hanny's Voorwerp (meaning Hanny's object in Dutch) is astounding because astronomers have never seen anything like it. Although galactic in scale, it is clearly not a galaxy because it does not contain any stars. That raises an obvious question: what is causing the gas to glow? Now a new survey of the region of sky seems to have solved the problem. The Voorwerp lies close to a spiral galaxy which astronomers now say hides a massive black hole at its center. The infall of matter into the black hole generates a cone of radiation emitted in a specific direction. The great cloud of gas that is Hanny's Voorwerp just happens to be in the firing line, ionizing the gas and causing it to glow green. That lays to rest an earlier theory that the cloud was reflecting an echo of light from a short galactic flare up that occurred 10,000 years ago. It also explains why Voorwerps are so rare: these radiation cones are highly directional so only occasionally do unlucky gas clouds get caught in the crossfire."

7 of 123 comments (clear)

  1. What doea a voorwerp look like? by Low+Ranked+Craig · · Score: 5, Informative
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    I still cannot find the droids I am looking for...
  2. Re:what determines the direction of the cone by Low+Ranked+Craig · · Score: 5, Informative

    If memory serves (not always reliable before coffee) the radiation emanates from the poles, and actually comes from the accretion disk, not the hole itself. I believe that all black holes rotate due to the fact that they retain the angular momentum from in-falling matter.

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    I still cannot find the droids I am looking for...
  3. Voorwerpen by Anonymous Coward · · Score: 5, Informative

    Plural of voorwerp is voorwerpen (not voorwerps).

    1. Re:Voorwerpen by Gorath99 · · Score: 3, Informative

      For the record, "veerworp" would be feather-toss in Dutch. ;-)

  4. 1080p? by WonkoDSane · · Score: 4, Informative

    Put horizontally and vertically oriented quasars lined up in a perpendicular plane on the line between the black hole and the Voorwerp and you have just created the universe's largest TV screen.

  5. Re:Science! by grasshoppa · · Score: 2, Informative

    I quote one of my favorite historical figures ( strictly because he was an arrogant asshole );

    "Fix Reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve the homage of reason than of blindfolded fear." - T. Jefferson

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    Mod me down with all of your hatred and your journey towards the dark side will be complete!
  6. Re:what determines the direction of the cone by Abcd1234 · · Score: 4, Informative

    Actually, as I understand it, most (maybe all) black holes spin due to momentum both already present before their collapse, and imparted during the collapse.

    You are quite correct about the jets, though. Here's a classic example.