Messier 10 or M10 (also designated NGC 6254) is a w:globular cluster in the w:constellation of w:Ophiuchus.

Messier 10 Courtesy Hunter Wilson
Messier 10 Courtesy Hunter Wilson
M10
Messier 10 by Hubble Space Telescope; 3.5′ view
Credit: NASA/STScI/WikiSky
Observation data (J2000 epoch)
ClassVII
ConstellationOphiuchus
Right ascension16h 57m 08.99s[1]
Declination-04° 05′ 57.6″[1]
Distance14.3 kly (4.4 kpc)
Apparent magnitude (V)6.4[1]
Apparent dimensions (V)20′.0
Physical characteristics
Masskg ( M)
Radius41.6 ly [2]
Other designationsNGC 6254[1]

The object was discovered by w:Charles Messier on w:May 29 w:1764, who cataloged it as number 10 in his list. He described it as a "w:nebula without stars", but later study revealed it as a globular cluster of thousands of stars.

M10 has an apparent diameter of some 20 w:arcminutes, about two-thirds of the w:apparent diameter of the w:Moon. Viewed through medium-sized w:telescopes it appears about half that size (8' to 9'), as its bright core is only 35 light-years across. M10 has a spatial w:diameter of 83 w:light-years and is estimated to be 14,300 light-years away from Earth. Four w:variable stars have been discovered in this cluster.

References

  1. a b c d "SIMBAD Astronomical Database". Results for NGC 6254. Retrieved 2006-11-15.
  2. distance × sin( diameter_angle / 2 ) = 41.6 ly. radius