Category: Astronomy

I shot this Thursday night at the River Ridge Observatory with my C11 at prime focus, all 2800mm of focal length. It’s 30 two minute images combined. This is the Dumbbell Nebula (aka Apple Core Nebula or Messier 27) in the constellation of Vulpecula (the little fox). It is a planetary nebula, one of the brightest, which are the remains of the extended atmosphere of all but dead stars called white dwarfs. The radiation from the very hot white dwarf excites the molecules in this nebula and causes it to glow. It is not symmetric because we are seeing it from the side and either the top and bottom of the apple or the two “bites” taken out of it represent the rotational axis of the white dwarf. I’m not sure which.

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.

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.