accretion disk

American  

noun

Astronomy.

1. the rapidly spinning disk of gas that forms around the more compact component of a close binary star system as mass is transferred to the compact companion from the primary star.

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accretion disk Scientific  

1. A spinning disk of gas and dust surrounding a celestial object with an intense gravitational field, such as a star or a black hole. In binary star systems, the gravitational attraction of the denser star can pull matter from the other star into an accretion disk in its own orbit. The material in the accretion disk eventually spirals into the attracting star and adds to its mass. The gas in accretion disks that surround black holes becomes condensed and heated as it is sucked into the hole, emitting x-rays and other radiation that provide evidence for the presence of the black hole.

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Etymology

Origin of accretion disk

First recorded in 1975–80

Example Sentences

Even so, the system rapidly accumulates matter within an accretion disk, placing it in a category called "intermediate polars."

From Science Daily

In intermediate polar systems, gas forms a rotating accretion disk while also being drawn toward the white dwarf's magnetic poles.

From Science Daily

This points to changes in how the accretion disk and corona interact over roughly the last 6.5 billions of years.

From Science Daily

"Finding such a well-organized spiral disk at this epoch tells us that the physical processes driving galaxy formation -- gas accretion, disk settling, and possibly the development of spiral density waves -- can operate far more efficiently than current models predict. It's forcing us to rethink our theoretical framework."

From Science Daily

Active galactic nuclei occur when material spirals into a galaxy's central black hole, forming an extremely hot accretion disk.

From Science Daily