accretion disc
 

* 1.A disc-like structure of dust and gas which forms around the massive object at the centre of a region undergoing gravitational collapse. It is caused because the regions of collapse are not stationary and move through space. Specifically they are in orbit around the centre of the galaxy. Thus, they have angular momentum and as they fall into the potential well of the massive object, instead of falling straight onto the central body, they spiral downwards. This causes the material to build up in a disc around the object. The more mass contained by the object the deeper its potential well and the faster the material in the accretion disc will swirl around it. Thus, the more heating the disc will suffer and the more energy it will release in the form of electromagnetic radiation. Accretion discs are, primarily, found around protostars and black holes

English Related Words* accretion

* accretion (of a discount)

* accretionary

* attracted disc electrometer

* audio compact disc

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* brake disc

* cardan disc

* cervical disc syndrome

* choked disc

* clutch disc

* clutch driving disc

* cluth disc

* colour disc

* compact disc