Accretion

Accretion- The term accretion describes the growth of a massive object by gravitationally attracting more matter. This is commonly done through the formation of an accretion disk of gaseous matter. We find accretion disks around smaller stars or stellar remnants in a close binary, or around black holes in the centers of galaxies.

Accretion disks form in non-magnetic cataclysmic variable binaries

Accretion also refers to the collision and sticking of microscopic dust and ice particles in protoplanetary discs and protoplanet systems, leading to planetesimals which gravitationally accrete more small particles and other planetesimals.

Images courtesy Mark A. Garlick

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