h and chi Persei

The double cluster in the constellation Perseus, normally known by its Greek designation transliterated. chi Persei (NGC884, on the left) and h Persei (NGC869) are about 7000 light-years away and less than 100 light-years apart. Although open clusters are quite common, this pair is exceptional due to the large number of young bright O and B stars in each, and their closeness whilst still being clearly distinguished. This color picture was made from CCD images taken in September 1997 at the Burrell Schmidt telescope of the Warner and Swasey Observatory of the Case Western Reserve University, located on Kitt Peak in southwestern Arizona.