User:Johnf5007/Intracluster Stars

In astronomy, intracluster stars (sometimes referred to as "intracluster light," "ICL, " or "diffuse light"), are stars that are gravitationally unbound to any galaxy, but are still gravitationally bound within a galaxy cluster. Intracluster stars are distinct from the Intracluster Medium, which is gaseous, and is mostly detected through its X-ray emission. The intracluster light primarily emits light in the optical and infrared portions of the spectrum, as most stars do.

History
The concept of intracluster light was first proposed in 1951 by the astronomer Fritz Zwicky

Observations of Intracluster Stars
Intracluster stars have been observed in two different ways: by observing individual bright stars in nearby galaxy clusters, or by observing light from many stars in more distant galaxy clusters.

Observations of intracluster red giant stars have been made by the Hubble Space Telescope .

Intracluster Planetary Nebulae have

Intracluster supernovae have also been detected in several galaxy clusters. Thus far, all of these objects are

Additionally, deep optical imaging of galaxy clusters can reveal intracluster starlight as faint features far away from any galaxy. Due to its nearby distance, the Virgo Cluster of galaxies has been heavily studied, and images of the intracluster light detected there has been made.

Estimates of the total amount of intracluster stars are very uncertain, due to the difficulty. However, various astronomers have quoted. In terms of the total mass of galaxy clusters, intracluster stars are a small fraction

Theoretical Origins of Intracluster Stars
Generally, intracluster light is believed to be produced from two main mechanisms. First, some intracluster stars have been known to be directly formed in the intracluster environment. In all of these cases thus far, neutral intracluster gas has been present.

Second, it is believed that intracluster stars were once formed within a galaxy, as normal stars are, but then the star was removed from the galaxy due to the effects of gravity. In a galaxy cluster, this happens as galaxy gravitationally interacts with other cluster galaxies, and the dark matter

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