Worlds of David Darling
Encyclopedia of Science
Home > Encyclopedia of Science

gravitational instability

Gravitational instability is a situation in which an object's self-gravity exceeds opposing forces such as internal gas pressure or material rigidity, and the object collapses. For a gas, gravitational instability sets in when the mass is greater than a certain critical value known as the Jean's mass. In the early universe, instabilities were large enough to produce galaxies and clusters of galaxies.

Related category