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
Famous quotes containing the word composition:
“The composition of a tragedy requires testicles.”
—Voltaire [François Marie Arouet] (1694–1778)
“Give a scientist a problem and he will probably provide a solution; historians and sociologists, by contrast, can offer only opinions. Ask a dozen chemists the composition of an organic compound such as methane, and within a short time all twelve will have come up with the same solution of CH4. Ask, however, a dozen economists or sociologists to provide policies to reduce unemployment or the level of crime and twelve widely differing opinions are likely to be offered.”
—Derek Gjertsen, British scientist, author. Science and Philosophy: Past and Present, ch. 3, Penguin (1989)
“When I think of God, when I think of him as existent, and when I believe him to be existent, my idea of him neither increases nor diminishes. But as it is certain there is a great difference betwixt the simple conception of the existence of an object, and the belief of it, and as this difference lies not in the parts or composition of the idea which we conceive; it follows, that it must lie in the manner in which we conceive it.”
—David Hume (1711–1776)