Credit & Copyright: A. Hobart, CXCExplanation: In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes. The gas surrounding GRO J1655-40, for example, has been found to display an unusual flickering at a rate of 450 times a second. Given a previous mass estimate for the central object of seven times the mass of our Sun, the rate of the fast flickering can be explained by a black hole that is rotating very rapidly. What physical mechanisms actually cause the flickering -- and a slower quasi-periodic oscillation (QPO) -- in accretion disks surrounding black holes and neutron stars remains a topic of much research.
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Publications with keywords: black hole
Publications with words: black hole
- The Doubly Warped World of Binary Black Holes
- The Galaxy, the Jet, and a Famous Black Hole
- When Black Holes Collide
- M87s Central Black Hole in Polarized Light
- GW190521: Unexpected Black Holes Collide
- APOD: 2020 August 25 Á Visualization: A Black Hole Accretion Disk
- A Black Hole Disrupts a Passing Star