4/4/2021 Some Galaxies

Here are a couple images taken last Saturday night at the River Ridge Observatory. Both were taken with my 11″ SCT at f/1.9 and were made from 12 five minute subs. This configuration is not ideal for single galaxies, with a few exceptions, but okay for galaxy clusters.First we have the Leo Triplet which is well positioned in the evening sky after dark right now. The triplet is made up of spiral galaxies Messier 65 & 66 and NGC 3628 aka the Hamburger Galaxy.The next image is of Markarian’s Chain, a string of galaxies making up part of the vast Virgo Cluster (which contains 1300 or more galaxies). The two brightest galaxies on the left are Messier 84 & 86 while the other galaxies around them and extending to that relaxed J have NGC designations. There are many catalogs of objects in astronomy, perhaps the most famous is the Messier Catalog, another the Herschel Catalog both named after the astronomer who created them. The New General Catalog is close to 200 years old and might be the first organized catalog. It uses a 4 digit number that increases from the zero point over the prime meridian which runs through the UK. It was good to be the world empire at the time. Anyway, these are just a few galaxies to be seen in the Virgo Cluster.

4/4/2021 Omega Centauri

Omega Centauri is the single largest globular cluster orbiting the Milky Way galaxy. At an estimated 10 million stars it is about ten times larger than the next largest. It is so large in fact that many astronomers believe it is the core of a disrupted dwarf galaxy. It is believed to even have a central black hole like any self respecting galaxy would. Also, the spectra of stars within it show much more variety than is typical for a globular cluster.

Omega Centauri has been my favorite globular cluster since I was a toddler, long before anyone suspected it had extra-galactic origins. My favorite, in part because it is so hard to observe from Arkansas where it never ventures more than 7 degrees above the horizon. That is the width of four fingers held at arm’s length. Last night, at the River Ridge Observatory, my telescope was almost horizontal as it pointed at this big ball of stars just above the horizon.

4/2/2021 The Seagull Nebula

Thursday night I went up to the River Ridge Observatory to do some narrow band imaging. One of my targets was IC 2177 aka the Seagull Nebula in the constellation of Monoceros, the Unicorn. This is an emission nebula, meaning it’s relatively warm and glowing as opposed to reflecting light that hits it. What we can see here are the head in the upper left and the wings diagonally. Actually, I’ve always thought it looked more like a flying turtle than sea gull but either way he looks happy. This was made with my 11″ SCT at f/1.9 using a dual narrowband filter and my ZWO ASI294MC Pro. A total of sixty minutes integration.