I have a moderately large library of astronomy books, but I'm only going to mention the books I use regularly in my observing programs. In the old days I had three books: Norton's Star Atlas, Olcott's Field Guide, and Menzel's Field Guide. I still make use of the first two in my Space Eye project. Using a 2" refractor occasionally alongside a 12" reflector is pretty weird, I know. But I get a kick at what the Vixen scope can do. Norton and Olcott both include double star tests for 2" scopes. I will continue to use the 2" refractor off and on, depending on time available. A few nights ago I had another look at M11, and it was a pleasing view in its own way. I tried to locate oc 6709 in Aquila but was unsuccessful. That is one of my favourite small clusters.
Turning now to my main observing library, I mostly use Uranometria (1 volume edition) for all my observing work, alongside its companion volume, The Uranometria Deep Sky Field Guide. Both volumes are essential to my observing program. Supplementary books are The Night Sky Observer's Guide (2 volumes) by Kepple and Sanner, along with Atlas of Star Clusters (2 volumes) by Mike Swan, published by the Webb Deep Sky Society. For lunar work I use Atlas of the Moon by A. Rukl, published by Astronomy back in the day. I also use The Stars: A New Way to See Them by H A Rey, children's classic that is still very useful today, especially when talking about constellations with groups or individuals unfamiliar with the night sky.
I also have a whole host of books I use to use a lot but seldom refer to now, such as Burham's 3 volume Celestial Handbook, Observing Handbook of Deep-Sky Objects by Luginbuhl and Skiff, and the on-going series Annals of the Deep Sky by Kanipe and Webb. However, I stopped purchasing these books when they published Cassiopeia and left out my favourite open cluster, oc 7789. How this could have been left out I don't know, but it made me stop buying their books.
In future columns I will discuss some of these books in detail, and why I think they are essential tools. I will also list my favourite and most useful websites. My list is small but vital to my program.
Time to move on. Messier 2 is one of 29 globular clusters in the full list of 110 objects. Here are its stats: Messier 2, gc 7089: 16', Vis. mag. 6.6, Br. star mag. 13. Here is my first report: "Though I've been using a telescope since 1969, I first saw M 2 on August 29th, 1994. Skies were near perfect and the temperature was around 13 C. It was swept up in the finder of my Edmund 8" reflector, and at 36x in the main viewfinder the globular cluster was very large and bright. A very few outer stars were resolving. At 59x it was very granular. A bright star was noted just preceding the intense core. 72x gave very minimal resolution, with the outer areas showing quite large. At 118x the very brightest members began to resolve. 169x showed a tiny swarm of stars resolving around the now irregularly-shaped bright core. There was an ovalness to the very center. 200x gave fair resolution to the very rim of the core. Resolution improved with 254x, with core now quite magnificent and crossed with stars. This is an object not to be missed with an 8" scope."
Next came a view of M 2 using my 12" Orion Dob. It occurred on September 2nd, 2024. I remarked that it was night of rare transparency, with excellent conditions and a temp around 50 F. Here are my notes: "This is the kind of showpiece that a 12" aperture was made for!. First viewed in 1994 with the 8", tonight I began at 107x and full aperture. The cluster is compact but still a good size, with a large and bright central area. there is already good resolution, especially in the outer regions. 120x provides a stunning view, with some resolution to the core. At 166x the resolution of stars becomes spellbinding, especially near and now in the bright core. 231x and 333x provide the best views, and M 2 resembles an amateur astronomer's stellar fantasy come true! The core is bright and tightly packed with stars. Streams and lines of stars resolve across the entire object. M 2 is a wonder in a 12" Dob!"
I followed up on October 2nd of 2024 with Space Eye, my 2" Vixen refractor. This is truly a superior instrument for its size. Here are my notes: "This globular cluster looked fantastic in the 2"! It was very bright and a few of the nearby stars also appear in the field. The cluster shows a large, bright core and a good size surrounding fainter haze. I was happily surprised at its brightness! It wasn't difficult to locate, despite not using the instrument since November 2016." Why look at it with such a small aperture? Think of Messier and why he made the list. Does M 2 appear comet-like in a small refractor? It sure does.
See you next time.
Mapman Mike
No comments:
Post a Comment