Messier Index/M72

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Messier 72
M72 Hubble WikiSky.jpg
M72 from w:Hubble Space Telescope; 3.44′ view
Credit: w:NASA/w:STScI/w:WikiSky
Observation data (w:J2000 epoch)
Constellation Aquarius
Right ascension 20h 53m 27.91s[1]
Declination -12° 32′ 13.4″[1]
Distance 53-62 kly (16-19 kpc)
Physical characteristics
Mass kg ( M{\odot})
Notable features Contains several blue giants
Other designations NGC 6981, GCl 118[1]

Messier 72 (also known as M72 or NGC 6981) is a w:globular cluster in the Aquarius constellation discovered by w:Pierre Méchain in w:August 29 w:1780. w:Charles Messier looked for it on the following w:October 4 and 5, and included it in his catalog. Both decided that it was a faint nebula not a cluster as is now believed. Using 10-inch (250 mm) telescopes, viewing the cluster is difficult resulting in only a view of a faint blurry picture, However using Kopernicks' 20-inch (510 mm) telescope resolution is highly increased. M72 is located at about 53,000 w:light-years away from w:Earth and lies in a considerable distance beyond the w:Galactic Center. Another source states that the cluster is 62,000 light-years away, with a diameter of 42 light-years. Generally considered a young cluster, the cluster has several blue giants, yet star clusters generally contain the oldest stars.

External links

References

  1. a b c "SIMBAD Astronomical Database". Results for NGC 6981. http://simbad.u-strasbg.fr/Simbad. Retrieved 2006-11-16.