Composition
There are three main components of a galaxy cluster. They are tabulated below:
| Name of the components | Mass fraction | Description |
|---|---|---|
| Galaxies | 1% | In optical observations only galaxies are visible |
| Intergalactic gas in ICM | 9% | Plasma between the galaxies at high temperature. Emit x-ray radiation through thermal bremsstrahlung mechanism. |
| Dark matter | 90% | Most massive component, cannot be detected optically, inferred through gravitational interactions. |
Read more about this topic: Galaxy Cluster
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