Category: Deep Sky

The last object of Saturday night/Sunday morning was Messier 15, the Great Pegasus Star Cluster. This was shot with my C11 at f/6.3 for 90 minutes.

Per Wikipedia: M 15 is about 35,700 light-years from Earth, and 175 light-years in diameter. It has an absolute magnitude of −9.2, which translates to a total luminosity of 360,000 times that of the Sun. Messier 15 is one of the most densely packed globulars known in the Milky Way galaxy. Its core has undergone a contraction known as “core collapse” and it has a central density cusp with an enormous number of stars surrounding what may be a central black hole.

Saturday night was a good night at the River Ridge Observatory, good and warm and humid. Several of us were there. Everyone’s cooled cameras were struggling to stay cool.

I decided to shoot the Flying Bat Nebula, aka SH2-129, in Cepheus. This is four hours with my Samyang 135 and an L-Enhance F2 filter. I think I can barely make out the “Squid Nebula” inside the bat, almost exactly in the center. It is a faint green nebula that looks more like a squid than this looks like a bat. After this success, I think I will attempt to shoot this over several nights to build up the signal.

I’m not a big fan of open star clusters. These loose aggregations of dozens of stars tend to be a little boring. This one, however, has some history behind it. Originally, it represented the tail of Leo (the lion) but one of the Ptolemys renamed it after Queen Berenice, so it’s other name is “Berenice’s Hair”. The field of view here is 10 degrees by 6.6 degrees so this cluster is quite large and at a measured distance of 280 light-years, it is nearby as well. Note what I initially thought were three blemishes but turned out to be galaxies in the lower left and upper left.