M15 is (NGC 7078) is a globular cluster Pegasus. It is one of the oldest known globular clusters. It is also notable for containing a large number of variable stars (112) and pulsars (8), including one double neutron star system, M15-C. It also contains Pease 1, the first planetary nebula discovered within a globular cluster, back in 1928.

This is a fun little dataset in RGB (10mn each, 30mn integration total). The initial goal of this image was to try to generate Hertzsprung-Russell diagrams in Python from the star color and brightness, like this. I have not had time yet.

After I became aware of Pease 1, a secondary goal became to image the diminutive nebula from the color dataset. It is possible (see below), although at the limit of what this low effort image can yield. Imaging Pease 1 in a more serious way would warrant to revisit this target with Ha filter, which I may do.

In case you wonder where is Pease 1, it is identified in green (PK065-27.1)
Even on this low effort RGB dataset, it is possible to see Pease 1 when torturing the histogram of the linear image. The green cross is generated by Pixinsight Annotation script, based on plate solving of the image.
%d bloggers like this: