|Open Cluster M103 in Cassiopeia
M103 is a relatively sparse open cluster, containing only about 40 stars, at a distance of about 9000 light years.
Although Messier listed this object in his catalog, he based this inclusion on the reports of Pierre Mechain, who
discovered this cluster in 1781. M103 forms a glittering triangular jewel in a small telescope.
This cluster is more complex than a casual glance might imply. First, the brightest star, forming the bottom apex of
the triangular cluster, is actually a double star that is not even a part of the cluster. Its companion is the slightly
dimmer star just above it. Second, whereas most of the cluster's stars are blue, one of the brightest is a red giant
star, appearing YELLOW located just to the right of the center of the cluster.
A total of 90 minutes in RGB was combined to give this image. An ST10 camera used a Celestron 8" scope at
prime focus to get this image.
As we live a life of ease
Everyone of us has all we need
Sky of blue and sea of green
In our yellow submarine
----- the Beatles