Accretion is the growth of a massive object by gravitationally attracting more matter in an accretion disc. Accretion discs are common around smaller stars or black holes in the centers of spiral galaxies. Some dynamics in the disc are necessary to allow orbiting gas to lose angular momentum and fall onto the central massive object. Occasionally, this can result in stellar surface fusion.

ACRETION is a collaborative work started by Teurk & Simon Rouby.