Messier Index/M56

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Messier 56
Messier 56 by w:Hubble Space Telescope. 3.6′ view
Credit: w:NASA/w:STScI/w:WikiSky
Observation data (w:J2000 epoch)
ClassX
ConstellationLyra
Right ascension19h 16m 35.50s[1]
Declination+30° 11′ 04.2″[1]
Distance32.9 kly[2] (10.1 kpc)
Apparent magnitude (V)+8.3
Apparent dimensions (V)8′.8
Physical characteristics
Masskg ( M)
Radius42 ly[3]
Other designationsM56, NGC 6779, GCl 110[1]

Messier 56 (also known as M56 or NGC 6779) is a w:globular cluster in the w:constellation w:Lyra. It was discovered by w:Charles Messier in w:1779. M56 is at a distance of about 32,900 w:light-years from w:Earth and measures roughly 84 light-years across.

The brightest w:stars in M56 are of 13th magnitude while it contains only about a dozen known w: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).

External links

References

  1. a b c "SIMBAD Astronomical Database". Results for NGC 6779. Retrieved 2006-11-16.
  2. w: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
  3. distance × sin( diameter_angle / 2 ) = 42 ly. radius