With a visual magnitude of 5.2mag Messier 22 (M22) is one of the brightest Globular Clusters (GC) in the sky.It could be resolved into single stars with an instrumet of an apertur of only 8-inches.
Its apparent diameter is the size of the full moon,what tells us,that M22 is one the nearer GC´s to our earth,with a real distance of about 10.000 light-years.The number of stars count to roughly 70.000.
M22 is metal-poor and like 3 other GC´s it contains a planetary nebula and also 2 black holes could be identified in it till now.
It was first seen in 1665 by Abraham Ihle.1764 Cahrles Messier included it to his cataloge.
position (epoch 2000):
Right ascension: 18h 36m 23.90s
Declination: –23° 54′ 17.1"
RGB 12x300sec each,a total of 3.0 hours,bin1x1 remote controlled
80cm f/7 Astro-Optik Keller Cassegrain+corrector
FLI Proline 16803,Baader-Filters
PROMPT7 CTIO/UNC Chile
aquisition and processing: Bernd Flach-Wilken
this picture shows M22 in the complete field of our camera,which measures 22´x22´:
Click HERE for a full resolution picture of 19´x19´arc-sec.size