M 21

M21 is a cluster which shows quite a strong concentration toward its center. According to Burnham, S.N. Svolopoulos, in 1953, has demonstrated the membership of 57 stars, the brightest of which are giants of spectral type B0.

As it is situated close to the Trifid Nebula, many images showing the Lagoon-Trifid region do also show M21.

Right ascension	18 : 1.8 (hours : minutes)
Declination	-22 : 30 (degrees : minutes)
Distance	3.0 (light-years*10^3)
Visual magnitude	6.5