Changes

In the 1980s astronomers discovered that the visible matter in rotating galaxies has insufficient [[gravity]] to hold the galaxy together. The term ''dark matter'' refers to whatever is generating the extra [[gravity]].  

Dark matter is a form of matter that has never been observed, which has been invented by astronomers in order to supplement the shortcomings of Big Bang cosmology and the [[theory of relativity]].  In the 1980s astronomers discovered that the visible matter in rotating galaxies has insufficient [[gravity]] to hold the galaxy together. The term ''dark matter'' refers to whatever is generating the extra [[gravity]].  

Academic [[physicist]]s feel that most of the [[mass]] in a [[galaxy]] is unseen dark matter, and that known substances like [[neutrino]]s, [[black holes]], and dead [[star]]s are insufficient. Many physicists believe that the dark matter is some as-yet-undiscovered subatomic particle, such as the axion, Higgs, or lightest supersymmetric particle.

Academic [[physicist]]s feel that most of the [[mass]] in a [[galaxy]] is unseen dark matter, and that known substances like [[neutrino]]s, [[black holes]], and dead [[star]]s are insufficient. Many physicists believe that the dark matter is some as-yet-undiscovered subatomic particle, such as the axion, Higgs, or lightest supersymmetric particle.

[[category:physics]]

[[category:physics]]