Английская Википедия:Helmi stream
Шаблон:Short description The Helmi Stream is a stellar stream of the Milky Way galaxy. It started as a dwarf galaxy, now absorbed by the Milky Way as a stream. It was discovered in 1999, is formed of old stars deficient in heavy elements, and has a mass of 10 to 100 million solar masses. It was absorbed by the Milky Way some 6 to 9 billion years ago.[1]
The stream was named after Amina Helmi, who discovered this stellar stream after noticing this group of stars all moving at the same speed and in the same direction.[2][3] The Helmi Stream discovery affirmed theories that the merging of galaxies played a significant role in creating the giant structures of the Milky Way galaxy.[2]
Extragalactic planet
The Helmi stream was home to the first planet purportedly of extragalactic origin, orbiting the star HIP 13044.[1] Further analysis of radial velocity data failed to confirm the discovery.[4]
See also
References
Шаблон:Star-cluster-stub
Шаблон:Spiral-galaxy-stub
- ↑ 1,0 1,1 Scientific American, "Extragalactic Expat: Newfound Exoplanet Likely Came from Another Galaxy", John Matson , 18 November 2010
- ↑ 2,0 2,1 Шаблон:Cite web
- ↑ Шаблон:Cite journal
- ↑ Шаблон:Cite journal
