The first object(s) that I ever observed through the 9″ refractor atop The University of Texas Painter Hall was the Perseus Double Cluster. It was in the late fall of 1965. It was a breathtaking sight.
NGC884 and 869 are open clusters in the Perseus arm of the Milky Way. There are four main arms in our galaxy, and we are in none of them – seems apt to me for a species that once considered itself at the center of everything. The arms are named Norma-Cygnus, Sagittarius, Perseus, and Scutum-Crux arms – named after the constellations which are features of each arm. We’re in a minor arm called the Orion Spur – an appropriate location for us, I think.
These two clusters are relatively young, and are comprised largely of young hot (white and blue) stars. Together with a surrounding halo of stars, they are thought to weigh in at 20,000 solar masses. NGC884 has a group of Red Supergiant stars as well. These are clearly visible in the images below albeit better in the cropped picture.
The pictures below are a cropped and full-field image respectively from the composite of ten, 6-minute frames.
It’s been 57 years since I first appreciated the Perseus Double Cluster from a cold perch atop the sixth floor of what was then the UT Physics Building; it is still a glorious sight.
How magnificent picture. Thank for the explanation of your heavenly findings.