Open clusters and nebulae

Started by kulginov, 12/08/2004 02:00PM
Posted 12/08/2004 02:00PM Opening Post
Yesterday we were blessed by the first clear night in almost two weeks. 80mm of aperture is unimpared when it comes to open clusters, and I spent a couple of hours looking at OC and DN. The find of the day was NGC7209, a very delicate open cluster in Lacerta. It looks very small at low power, but resolves into a lot of "small" (in Herschel sense of the word) beautiful stars that fill my field of view at 100x (27 arc min). I failed to find much beauty in M39 again, but was fascinated by M34 with its pagoda shape. Nebulosity in NGC281 looked exactly as in the book at 22x. Merope nebula was kind of easy with UHC (I guess the filter kills most of the light pollution even this is a reflection nebula - as Inge has noted here).

In the end Orion had risen high enough and I looked at M42/M43. The night was dark, and the nebula was so large and bright that I almost fell over! The best view was at 22x (my new 18mm Ultima), it was great both with UHC and unfiltered, with Trapezium well resolved. I still strongly suspect that we cannot see all its splendour at this latitude (57N)... After that I checked Rosette nebula - and saw it for the first time. I couldn't make out the shape, but when I moved the scope away from the central cluster, the sky suddenly would become jet-black. Finally I tried to see it with naked eye through the UHC filter - and saw it as an "out-of-focus star". It disappeared without the filter.

Dmitri
Posted 12/08/2004 04:47PM #1
Dimitri,
Sounds like you had a nice evening out. Glad to hear it. Clouds have been a central theme here in Wisconsin (USA) for what seems like weeks now. sad
I was curious about your report, specifically the part about the viewing the Rosette nebula via the naked eye and a UHC filter. I have never heard of this being possible and I'm most certainly intrigued by the prospect. grin What is the naked eye limiting magnitude at your location? Also, what telescope were you using when you were viewing the Rosette? I recently discovered a very nice observing location only 10 miles from my home. This location has some skyglow; however, most of it hugs the horizon to the south and west. I figured this would be a great spot to try to observe the Rosette with an 80mm f/5 refractor. From dark sky locations I've had great success viewing the North American nebula, Helix nebula and Veil nebula with that little refractor. It's quite fun to enjoy those wide field views. smile
In any event, I look forward to hearing back from you regarding my questions.
Most Sincerely,
Chris Hanrahan
Posted 12/09/2004 01:27PM #2
I really hope for a clear night soon. Always look forward to the time when the nebulosity of Orion and Monoceros gets favourably placed for observation.

With a small scope I would go for Hubble's variable nebula (NGC2261). Monoceros contains other interesting nebulae too. Most famous, but probably least interesting viusally is the nebulosity involved in NGC2264 (Christmas Tree) with the Cone Nebula. The reflection nebulae NGC2245 and 2247 are far more interesting objects, although they are probably best suited for 10-inch scopes or larger. For observers equipped with the O-III filter and sufficient aperture I also recommend looking for detail in the Rosette nebula. Failing to spot the Horsehead in Orion, it is always a good comfort to see the bok globules of the Rosette with direct vision.

Inge S