Segue 3 is a dim star cluster in the Milky Way, discovered in 2010 in data obtained by Sloan's digital sky survey . [2] It is located in the constellation Pegasus at a distance of about 17 kpc from the Sun and moves away from it at a speed of 167.1 ± 1.5 km / s. [one]
| Segue 3 | |
|---|---|
| Star cluster | |
| Research history | |
| opening date | |
| Observational data ( Age J2000.0 ) | |
| Right ascension | |
| Declination | |
| Distance | 55.1 ± 2.3 thousand, [1] St. years (16.9 ± 0.7 thousand, pc ) |
| Visible magnitude (V) | 14.9 [2] |
| Visible Dimensions (V) | 4.6 +0.4 −0.8 [1] |
| Constellation | Pegasus |
| physical characteristics | |
| Radius | 6.8 ± 1.3 St. years (2.1 ± 0.4 pc ) [1] |
Segue 3 is extremely dull - its absolute magnitude is estimated at -1.2 [2] or even about 0.0 ± 0.8 , [1] which means that the cluster is only 100-250 times brighter than the Sun. Its small radius of about 2.1 pc is typical of galactic globular clusters . [1] The cluster has a slightly flattened shape and shows some signs of destruction by tidal forces. [one]
The metallicity of Segue 3 stars [Fe / H] ≈ -1.7, which means that they contain 70 times less heavy elements than the Sun. These stars are over 12 billion years old. [1] Segue 3 seems to be one of the dimmest globular clusters of the Milky Way.
Notes
- ↑ 1 2 3 4 5 6 7 8 Fadely Ross , Willman Beth , Geha Marla , Walsh Shane , Muñoz Ricardo R. , Jerjen Helmut , Vargas Luis C. , Da Costa Gary S. SEGUE 3: AN OLD, EXTREMELY LOW LUMINOSITY STAR CLUSTER IN THE MILKY WAY's HALO // The Astronomical Journal. - 2011. - August 16 ( t. 142 , No. 3 ). - S. 88 . - ISSN 0004-6256 . - DOI : 10.1088 / 0004-6256 / 142/3/88 .
- ↑ 1 2 3 Belokurov V. , Walker MG , Evans NW , Gilmore G. , Irwin MJ , Just D. , Koposov S. , Mateo M. , Olszewski E. , Watkins L. , Wyrzykowski L. BIG FISH, LITTLE FISH: TWO NEW ULTRA-FAINT SATELLITES OF THE MILKY WAY // The Astrophysical Journal. - 2010. - March 5 ( t. 712 , No. 1 ). - S. L103 — L106 . - ISSN 2041-8205 . - DOI : 10.1088 / 2041-8205 / 712/1 / L103 .