Star current
As a stream of stars are stellar associations (ie loose groupings of stars with physically similar properties) or movement bunch referred to in a very similar movement towards one and speed galaxy orbiting. Elongated hydrogen clouds are also possible. Star currents arise from dwarf galaxies or globular star clusters that have been torn apart by tidal forces and distributed along their orbits.
The members circling near the Milky Way can often only be discovered with the help of stellar statistics , primarily on the basis of their own movement and age or star population .
List of star currents in the Milky Way System
| Surname | origin | Mass ( solar masses ) |
Length ( light years ) |
composition | Discovery year |
|---|---|---|---|---|---|
| Arcturus Stream | Former dwarf galaxy | Unknown | Unknown | Old metal poor stars | 1971 |
| Magellanic Current | Large and Small Magellanic Cloud | 200 million | 1 million | Hydrogen gas | 1972 |
| Sagittarius stream | Dwarf sagittarius elliptical galaxy | 100 million | 1 million | Diverse star types | 1994 |
| Helmi current | Former dwarf galaxy | 10 to 100 million | Wrapped around the Milky Way system several times | Old stars | 1999 |
| Palomar 5 stream | Globular cluster Palomar 5 | 5000 | 30,000 | Old stars | 2001 |
| Virgo stream | Former dwarf galaxy | 30,000 | 2001 | ||
| Monoceros ring | Canis Major Dwarf Galaxy | 100 million | 200,000 | Middle-aged stars | 2002 |
| Anticenter electricity | Former dwarf galaxy | Unknown | 30,000 | Old stars | 2006 |
| NGC-5466 stream | Globular cluster NGC 5466 | 10,000 | 60,000 | Very old stars | 2006 |
| Orphan stream | Dwarf galaxy Ursa Major II | 100,000 | 20,000 | Old stars | 2006 |
| Acheron stream | Globular clusters | 2007 | |||
| Cocytus Stream | Globular clusters | 2007 | |||
| Lethe stream | Globular clusters | 2007 | |||
| Styx stream | Former dwarf galaxy | 2007 | |||
| Cetus polar current | Former dwarf galaxy | Old stars | 2009 | ||
| Aquarius stream | Former dwarf galaxy | 30,000 | Old stars | 2010 | |
| Lamost 1 | Torn apart globular cluster | 21,000 | Middle age stars | 2015 | |
| Phoenix stream | 8000 | Old stars | 2016 | ||
| Fimbulthul Stream | Globular cluster Omega Centauri | 318 | 2019 | ||
| Pisces Eridanus Current | Torn apart star cluster or association | 2000 | 1300 | Very young (~ 120 million years) and near (260–870 light years ) electricity | 2019 |
| Nyx stream | Remnants of a disrupted dwarf galaxy - an early galaxy merger | approx. 200 stars | 2020 |
literature
Kathryn V. Johnston: Cosmic Fossil Hunt . In: Spektrum der Wissenschaft , May 2015, pp. 38–44
Web links
Wiktionary: Sternstrom - explanations of meanings, word origins, synonyms, translations
- Florian Freistetter: Star Stories Episode 177: Star currents and dwarf galaxies. In: scienceblogs. April 15, 2016, accessed April 16, 2016 .
Individual evidence
- ↑ Rodrigo Ibata, Gibson, Brad: The Shadows of Galactic Worlds . In: Spectrum of Science . September 2007, pp. 52-57.
- ↑ Amina Helmi, Simon DM White, P. Tim de Zeeuw, HongSheng Zhao: Debris streams in the solar neighborhood as relicts from the formation of the Milky Way . In: Nature . 402, June 18, 1999, pp. 53-55. doi : 10.1038 / 46980 . Retrieved April 25, 2015.
- ↑ a b c Rings around the galaxy , Astronomy. June 1, 2007. Retrieved June 7, 2007.
- ↑ a b c d Four New Stellar Debris Streams in the Galactic Halo . In: The Astrophysical Journal . 693, No. 2, 2009, pp. 1118-1127. bibcode : 2009ApJ ... 693.1118G .
- ^ Heidi Jo Newberg, Brian Yanny, Benjamin A. Willett: Discovery of a New, Polar-Orbiting Debris Stream in the Milky Way Stellar Halo . In: The Astrophysical Journal . 700, No. 2, July 10, 2009, pp. L61-L64. arxiv : 0906.3291 . bibcode : 2009ApJ ... 700L..61N . doi : 10.1088 / 0004-637X / 700/2 / L61 .
- Jump up ↑ John J. Vickers, Martin C. Smith, Yonghui Hou, Yuefei Wang, Yong Zhang: LAMOST 1: A Disrupted Satellite in the Constellation Draco . In: The Astrophysical Journal . 816, No. 1, December 23, 2015, p. L2 (5 pages). arxiv : 1512.05090 . bibcode : 2016ApJ ... 816L ... 2V . doi : 10.3847 / 2041-8205 / 816/1 / L2 .
- ^ E. Balbinot, B. Yanny, TS Li, B. Santiago, JL Marshall, DA Finley, A. Pieres, TMC Abbott, FB Abdalla, S. Allam, A. Benoit-Lévy: The Phoenix Stream: A Cold Stream in the Southern Hemisphere . In: Astrophysical Journal . 820, No. 1, March 2016, ISSN 0004-637X , p. 58. arxiv : 1509.04283 . bibcode : 2016ApJ ... 820 ... 58B . doi : 10.3847 / 0004-637X / 820/1/58 .
- ↑ Khyati Malhan: Ghostly Tributaries to our Galaxy: Catastrophic tale of the most massive globular cluster of the Milky Way . April 23, 2019.
- ↑ Jason L. Curtis, Marcel A. Agüeros, Eric E. Mamajek, Jason T. Wright, Jeffrey D. Cummings: TESS Reveals that the Nearby Pisces-Eridanus Stellar Stream is only 120 Myr Old . In: AJ . 158, No. 2, August 2019, ISSN 0004-6256 , p. 77. arxiv : 1905.10588 . bibcode : 2019AJ .... 158 ... 77C . doi : 10.3847 / 1538-3881 / ab2899 .
- ↑ Stefan Meingast, João Alves, Verena Fürnkranz: Extended stellar systems in the solar neighborhood. II. Discovery of a nearby 120 ° stellar stream in Gaia DR2 . In: A&A . 622, February 2019, ISSN 0004-6361 , p. L13. arxiv : 1901.06387 . bibcode : 2019A & A ... 622L..13M . doi : 10.1051 / 0004-6361 / 201834950 .
- ↑ ScitechDaily: Nyx: Stellar Stream of Stars Discovered in Milky Way That Originated in Another Galaxy of July 8, 2020
- ↑ Necib, L., Ostdiek, B., Lisanti, M. et al. : Evidence for a vast prograde stellar stream in the solar vicinity, in: Nat Astron from July 6, 2020, doi: 10.1038 / s41550-020-1131-2