M60-UCD1 is an ultra - compact dwarf galaxy located 54 million light-years from the Sun, next to the galaxy M60 ( NGC 4649 ) in the Virgo cluster . Half of its stellar mass is in the central spherical region with a diameter of 160 light years. [2]
| M60-UCD1 | |
|---|---|
| Galaxy | |
 | |
| Observational data ( Age J2000.0 ) | |
| Constellation | Virgo |
| Right ascension | |
| Declination | |
| Specifications | |
| Included in | |
| Distance | 54 million St. years old (16.5 Mpc) [1] |
| Absolute magnitude (V) | 14.2 [1] |
| Weight | |
| Radius | |
Content
Features
The mass of the M60-UCD1 is 140 million solar masses . Colors and the absence of color gradients indicate a homogeneous stellar population about 14.5 ± 0.5 billion years old [1] [4] (indistinguishable from the age of the Universe ). Their metallicity is approximately equal to the metallicity of the Sun. The dispersion of the orbital velocities of the innermost stars exceeds 100 km / s [4] due to the strong attraction of the central concentrated mass. The galactic core contains a bright and variable source of x-ray radiation [1] , presumably a supermassive black hole with a mass of 20 million solar masses (15% of the mass of the entire galaxy). [5] With this ratio of the mass of the black hole to the mass of the entire galaxy, M60-UCD1 is one of the galaxies with the strongest dominance of the black hole. [6]
It is believed that M60-UCD1 is the core of a much more massive galaxy, which lost a significant fraction of its material when interacting with the M60 galaxy about 10 billion years ago. Perhaps M60-UCD1 will be completely absorbed by the galaxy M60, while the central black holes of the two galaxies will merge. Perhaps earlier M60-UCD1 contained about 10 billion stars. [6]
As of 2013, it was the densest galaxy known: the concentration of stars is more than 100 per cubic light year. [7] As of 2014, M60-UCD1 was the smallest galaxy in size and mass containing a central black hole, and it was also considered the most massive of the known ultra-compact dwarf galaxies. [6] As of 2015, this galaxy is superior in density to M85-HCC1 and M59-UCD3 .
Literature
- Strader, Jay; Seth, Anil C .; Forbes, Duncan A .; Fabbiano, Giuseppina; Romanowsky, Aaron J .; Brodie, Jean P .; Conroy, Charlie; Caldwell, Nelson; Pota, Vincenzo; Usher, Christopher; Arnold, Jacob A .; "The Densest Galaxy", The Astrophysical Journal Letters , Volume 775, Issue 1, article id. L6, 6 pp., September 2013; DOI : 10.1088 / 2041-8205 / 775/1 / L6 ; arXiv : 1307.7707 ;
- Seth, Anil; van den Bosch, Remco; Mieske, Steffen; Baumgardt, Holger; den Brok, Mark; Strader, Jay; Neumayer, Nadine; Chilingarian, Igor; Hilker, Michael; McDermid, Richard; Brodie, Jean; Frank, Matthias; Walsh, Jonelle L .; "A Supermassive Black Hole in an Ultracompact Dwarf Galaxy", Nature , 513, pages 398-400, September 18, 2014; DOI : 10.1038 / nature13762 ; arXiv : 1409.4769 ;
Notes
- ↑ 1 2 3 4 5 6 Strader, J. et al. The Densest Galaxy (unknown) // The Astrophysical Journal. - 2013 .-- T. 775 . - S. L6 . - DOI : 10.1088 / 2041-8205 / 775/1 / L6 . - . - arXiv : 1307.7707 .
- ↑ Astronomers Discover Densest Galaxy Ever . ScienceDaily . Date of treatment June 21, 2018.
- ↑ Big surprises can come in small packages . www.spacetelescope.org . ESA / Hubble. Date of treatment September 22, 2014.
- ↑ 1 2 Seth, A. et al. A Supermassive Black Hole in an Ultracompact Dwarf Galaxy (Eng.) // Nature: journal. - 2014 .-- Vol. 513 . - P. 398-400 . - DOI : 10.1038 / nature13762 . - . - arXiv : 1409.4769 .
- ↑ M60-UCD1: An Ultra-Compact Dwarf Galaxy NASA Date of appeal September 25, 2013.
- ↑ 1 2 3 Smallest known galaxy with a supermassive black hole , ScienceNews (September 17, 2014).
- ↑ Evidence for densest galaxy in nearby universe (unavailable link) . Phys.org (September 24, 2013). Date of treatment September 25, 2013. Archived September 27, 2013.
Links
- Chandra X-Ray Observatory, "NASA's Hubble and Chandra Find Evidence for Densest Nearby Galaxy" , NASA, September 24, 2013
- ScienceDaily, "Evidence for Densest Nearby Galaxy," September 24, 2013
- ScienceDaily, "Astronomers Discover Densest Galaxy Ever" , September 24, 2013