Messier 56
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Messier 56 | |
More Images [1] |
|
Observation data (J2000 epoch) | |
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Class | X |
Constellation | Lyra |
Right ascension | 19h 16m 35.50s[1] |
Declination | +30° 11′ 04.2″[1] |
Distance | 32.9 kly[2] (10.1 kpc) |
Apparent magnitude (V) | +8.3 |
Apparent dimensions (V) | 8′.8 |
Physical characteristics | |
Mass | kg ( M) |
Radius | 42 ly[3] |
Other designations | M56, NGC 6779, GCl 110[1] |
See also: Globular cluster, List of globular clusters | |
Messier 56 (also known as M56 or NGC 6779) is a globular cluster in the constellation Lyra. It was discovered by Charles Messier in 1779. M56 is at a distance of about 32,900 light-years from Earth and measures roughly 84 light-years across.
The brightest stars in M56 are of 13th magnitude while it contains only about a dozen known variable stars like V6 (RV Tauri star; period: 90 days) or V1 (Cepheid: 1.510 days); other variable stars are V2 (irregular) and V3 (semiregular).
[edit] External links
[edit] References
- ^ a b c SIMBAD Astronomical Database. Results for NGC 6779. Retrieved on 2006-11-16.
- ^ Valentin D. Ivanov et al., Near Infrared Photometry of Galactic Globular Clusters M56 and M15. Extending the Red Giant Branch vs. Metallicity Calibration Towards Metal Poor Systems
- ^ distance × sin( diameter_angle / 2 ) = 42 ly. radius