Two Very Different Neighbours
Last night the skies cleared and with the moon not rising to well after midnight it seemed like a good night to observe. I had a list of galaxy targets from the Cloudy Nights Monthly EAA Challenge list. I made my way through the list and then turned my attention to my Astronomical League Globular Cluster list. There were two globs that I had listed, M53 and NGC5053. Both are in the constellation of Coma Berenices and lie less than a degree from each other, shown in the chart below. Coma was still in a good position to image and so I gave them a go.
M53 is a beautiful globular cluster that is 58,000 light years away. It was discovered by Johann Bode in 1775. It is a bright target which is easy to find, lying less than a degree from Alpha Com B. To me, it has the appearance of a pile of white and yellow diamonds against a black velvety background. The cluster has a Shapely Concentration of a V on a scale of I to XII with I being the most concentrated and XII being the least. The stars in the core of the cluster are extremely densely packed, eventually merging into a solid white-yellow glow.
NGC5053 appears as M53's poor neighbor. William Herschel discovered this cluster in 1784. He described it as an extremely faint cluster of extremely small stars." It is much more diffused as compared to M53. Its Shapley classification is XI making it one of the most diffuse globular clusters that we have. If you did not know it was a globular, you might mistake it for an open cluster. The stars of this cluster are fewer and fainter than M53. Both clusters are similar in size, and both lie at a similar distance from us. NGC5053 is thought to have been stripped off of a neighboring galaxy during a close encounter in the past. It is possible that it may have originally looked similar to M53 but had its stars ripped from it by the gravitational effects of the close encounter.
After grabbing these two globs the clock was showing midnight with the clouds rolling in and so I decided to pull the plug. The total for the night was 9 galaxies and 2 globs.
Clear Skies;
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