HOME |
M 28 - GLOBULAR CLUSTER
SAGITTARIUS
(ra: 18,24.5 / dec -24:52)
May 2009, Home Backyard in Martínez Buenos Aires, Argentina
DATA
TYPE: Globular Cluster
Apparent Magnitude: 6.9
Apparent Diameter: 11.2 arc minutes
DISTANCE: 18.600 lights years
IMAGE INFORMATION
SCOPE: Celestron C8 SCT working at f6 (roughly)
CAMERA: SXVF H9
GUIDING: William Optics Zenithstar 66 with WO 0.8 x fr/ff
IMAGE ACQUISITION: AstroArt 3.0 - Control Interface 3.72 plug in
FILTERS: Astronomik Type II - Atik Filter Wheel
Magnitude 4 Skies: Conditions - regular
EXPOSURES: LRGB (20,16,16,16)
PROCESSING: Calibrated in Images Plus Adaptive Add, CCD Sharp, Photoshop CS2
OBJECT DESCRIPTION AND IMAGE SESSION
Compared to its neighbour M22, M28 appears much smaller. However still a nice target to telescopes also because it is rather easy to find. Just about 1 degree from Lambda Sagittarius (the top bright star of the tea cup)
M28 presents a diameter of 60 lights years. It is hard to see in the photograph where the globular ends because the dense background star field. This cluster was an authentic discover of Charles Messier catalogued in July 27 1764, but is was William Hershel the first one who described this object as a cloud of stars.
(*) Source Seds