NGC 869 & 884
Object: NGC 869-884 The double cluster in Persei
Optics: Takahashi FSQ-106EDX f/5.0
Idas LPS filter
Camera: SBIG STL11Km
CCD temperature: -20°C
Exposure: 1X1 L-85min(17X5m), R-100min(20X5m), Gs-96min(R+B)/2, B-100min(20X5m)
Mount: Takahashi EM-200
Image processing: Maxim DL, PhotoshopCS4
Quebec, Qc,
Canada
October 31, 2011
NGC 869 "h Persei" (right) is an open cluster at a distance of about 7600 light years in the constellation of Perseus. It shines beside NGC 884 "chi Persei" (left and further east) to form the famous double cluster in Perseus. These clusters are physically close together and separated by a few hundred light years one of the other. Their apparent diameter is 30 arcmin and about the size of the Moon. Their actual diameter is estimated at approximately 60 light years. Visible to the naked eye in dark skies, they are known since antiquity and have been listed by the Greek astronomer Hipparchus. Each cluster contains more than a hundred stars that blend subtly with a very rich star field in the Milky Way. The double cluster offers a spectacular view in binoculars or small instruments. They are a favorite target of amateur astronomers.