Galaxy clusters
Other astronomical objects
Emission Nebulae - Reflection- and
Dark-Nebulae - Planetary Nebulae - Galaxies and Galaxy Groups - Starclusters and Asterisms - Supernova Remnants - Rented Telescopes - Nasa Picture of the day - Moon and Comets - Nightscapes an Milkyway - Startrails - Timelapse Movies
Galaxy clusters (also called galaxy clusters) are large collections of galaxies held together by their mutual gravitational pull. They are among the largest structures in the universe and can contain hundreds to thousands of galaxies. Here is a brief overview:
- Components: Galaxy clusters consist of galaxies (of various types, such as spiral, elliptical, or irregular), hot gas (intracluster medium, which often emits X-rays), and dark matter, which makes up a large portion of the mass and stabilizes the structure.
- Size and Mass: They extend over millions of light-years and typically have a mass of about 10^{14} to 10^{15} solar masses.
- Formation: Galaxy clusters form through the gravitational attraction of smaller groups of galaxies and matter over billions of years. They are part of the large-scale structure of the universe, forming a network of filaments, walls, and voids.
- Examples: Well-known galaxy clusters include the Virgo Cluster (approximately 54 million light-years away, containing our Milky Way) and the Coma Cluster.
- Significance: They are important for cosmology because they provide clues about the distribution of matter, the expansion of the universe, and the role of dark matter and dark energy.
