Palomar 5
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Globular cluster Palomar 5 |
|
|---|---|
| AladinLite | |
| Constellation | Snake |
|
Position equinox : J2000.0 , epoch : J2000.0 |
|
| Right ascension | 15 h 16 m 05 s |
| declination | -00 ° 06 ′ 41 ″ |
| Appearance | |
| Concentration class | XII |
| Brightness (visual) | +11.75 mag |
| Angular expansion | 6.9 ′ |
| Surface brightness | 24.7 mag / arcmin² |
|
Color excess E (BV) (redness) |
0.03 mag |
| Physical data | |
| Affiliation | Milky Way |
| Radial velocity | −58.6 ± 0.21 km / s |
| distance | 75.6 kLj (23.2 kpc ) |
| Absolute brightness | −5.17 mag |
| Dimensions | approx. 5000 M ☉ |
| Core radius | 3.6 '/ 79 light years |
| Tidal radius | 16.1 '/ 356 light years |
| Concentration lg (r t / r c ) | 0.74 |
| Age | 9.8 ± 1.4 billion years |
| Metallicity [Fe / H] | −1.4 |
| history | |
| discovery | Walter Baade |
| Catalog names | |
| GCl 32 • Pal 5 • UGC 9792 • MCG + 00-39-016 • CGCG 021-061 | |
Palomar 5 (short: Pal 5 ) is a globular star cluster in the constellation Snake . Pal 5 was discovered by Walter Baade in 1950 and rediscovered by Albert George Wilson in 1955 . With about 5,000 solar masses, it is one of the globally poorest known globular clusters.
Palomar 5 is about 75,700 light years away from us. It has been orbiting the Milky Way for about 10 billion years . During several passages through the plane of the Milky Way, Pal 5 gradually lost parts of its matter to the Milky Way. Part of the torn out matter formed two tidal arms about 15,000 light years long , also known as the Palomar 5 stellar current . The star stream moves with Pal 5 around the Milky Way and contains mostly low-mass stars . Overall, Pal 5 has so far suffered a loss of mass of approximately 50,000 solar masses.
In 110 million years Pal 5 will again move through the Milky Way. It will enter a star-rich area about 23,000 light years from the center . Here, Pal 5 is presumably completely absorbed by the Milky Way.
Palomar 5 has a semi-mass radius of 3.0 'and a velocity dispersion of 1.1 km / s.
Web links
- SEDS
- Press release from the Max Planck Society
- Spektrum .de: amateur recordings [1]
Individual evidence
- ^ A b c d William E. Harris: A Catalog of Parameters for Globular Clusters in the Milky Way . In: Astronomical Journal . tape 112 , no. 4 , 1996, pp. 1487–1488 , doi : 10.1086 / 118116 , bibcode : 1996AJ .... 112.1487H .
- ^ A b Eugene Vasiliev: Proper motions and dynamics of the Milky Way globular cluster system from Gaia DR2 . In: Monthly Notices of the Royal Astronomical Society . tape 484 , no. 2 , 2019, p. 2832–2850 , doi : 10.1093 / mnras / stz171 , arxiv : 1807.09775 , bibcode : 2019MNRAS.484.2832V .
- ↑ M. Salaris, A. Weiss: Homogeneous age dating of 55 Galactic globular clusters. Clues to the Galaxy formation mechanisms . In: Astronomy and Astrophysics . tape 388 , 2002, p. 492–503 , doi : 10.1051 / 0004-6361: 20020554 , arxiv : astro-ph / 0204410 , bibcode : 2002A & A ... 388..492S .