| NGC 6522 | |
|---|---|
 | |
| Observation data (J2000 epoch) | |
| Constellation | Sagittarius |
| Right ascension | 18h 03m 34.1s[1] |
| Declination | −30° 02′ 2.3″[1] |
| Distance | 25.1 kly (7.7 kpc)[2] |
| Apparent magnitude (V) | 8.3[3] |
| Apparent dimensions (V) | 16.4'[3] |
| Physical characteristics | |
| Mass | 3.00×105[2] M☉ |
| Metallicity | = –1.34[2] dex |
| Estimated age | 12.0 Gyr[4] |
| Other designations | GCl 82, C 1800-300[1] |
![{\displaystyle {\begin{smallmatrix}\left[{\ce {Fe}}/{\ce {H}}\right]\end{smallmatrix}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4c0821bd80891e071c08e7c7ee8e022baedf522c)
NGC 6522 is a globular cluster in the constellation Sagittarius. It is apparent magnitude 8.3, and diameter 16.4 arc minutes, and class VI with stars 16th magnitude and dimmer. It was discovered by William Herschel on June 24, 1784. It is centered in a region of the sky known as Baade's Window.[1][3]
NGC 6522 is possibly the oldest star cluster in the Milky Way,[5] with an age of more than 12 billion years.[6]
- ^ a b c d "SIMBAD Astronomical Database". Results for NGC 6522. Retrieved 2011-03-13.
- ^ a b c Cite error: The named reference
apj742_1_51was invoked but never defined (see the help page). - ^ a b c "NGC 6522". Retrieved 2020-09-23.
- ^ Cite error: The named reference
mnras385_4_1998was invoked but never defined (see the help page). - ^ "VLT-FLAMES Analysis of 8 giants in the Bulge Metal-poor Globular Cluster NGC 6522: Oldest Cluster in the Galaxy?" by B. Barbuy et al., 2009
- ^ "The universe's first stars were whirling dervishes", New Scientist by David Shiga, 30 April 2011, p. 20. "Imprints of fast-rotating massive stars in the Galactic Bulge" by Cristina Chiappini et al., Nature 472, pp. 454–457 (28 April 2011).