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20 July 2003: M57, M56, Albireo and Veil nebula

In the early morning of July 20th I wanted to observe Mars. I started my observing session on Saturday the 19th, about 21.10h UT. I first turned my telescope at Beta Cygni, or Albireo, the beautiful double star at the Swan's head. At 62.5 times it is a real gem. The A component, magnitude 3.1, has a yellow-orange color. The B component, magnitude 5.1 is white to blue-white. The separation of both components is 34 arc seconds. Because I live in a light polluted area, I tried to darken the background while observing Albireo, using two filters. First I tried the Lumicon Deepsky filter. This made the background darker, but the B-component got a very bright and intense blue color. Then I tried the Baader Sky Glow filter. This worked well for me. Albireo almost kept its original colours, and the sky was slightly darkened. Anyway, it's a beautiful pair, and I look at it every year. It is one of my favourite doubles.

After that I went to M57, the Ring Nebula in Lyra. I tried several magnifications, ranging from 62.5x to 444x. I also tried several filters during the observing session, but I fount this doughnut-shaped ring of "smoke" at its best at 133x, without any filter. A great sight, although it still wasn't really dark. I will try this one again at the end of august, when it is darker. From there I went to M56, a globular cluster about halfway between gamma Lyrae and Albireo. This looked just as a tiny fuzzy spot at 62.5x. At 166x it was already partly resolved.

From there I went into Cygnus again. I wanted to locate the Veil nebula, something I did not manage until now. As the Swan was right above me at zenith, it was very hard to use the finder scope of my low built telescope. I almost had to sit on the ground. But since a few months I have added another finder to my scope, the Telrad. With this accessory I managed to find the location where a part of the Veil nebula should be very quickly. This is how I did it. First I pointed the scope at Gamma Cygni, right at the centre of the swan. Then I centred the Telrad on the 2.5 magnitudes Epsilon Cygni, on the eastern "wing" of the swan. The outer 4-degree ring of the Telrad already touched the Veil nebula.

Veil Nebula

(Screenshot from TheSky for Macintosh by Software Bisque)

Then I moved the telescope to the south, until the outer ring of the Telrad lied over Epsilon Cygni. I looked three degrees to the south of Epsilon Cygni. There I detected the 4.2 magnitude star, 52 Cygni. It was situated just outside the 2-degree ring of the Telrad.

Veil Nebula

(Screenshot from TheSky for Macintosh by Software Bisque)

Next I centred the Telrad on 52 Cygni. I should be near the Western part of the Veil Nebula, NGC 6960. (This part is called the Network Nebula. The Eastern part, NGC 6292-6295 is sometimes called the Filamentary Nebula. The whole system has different names, the Bridal Veil Nebula, the Cirrus Nebula, the Cygnus Loop or just the Veil Nebula.) Anyway, as I stated I should be able to detect the western segment, because 52 Cygni lies in the middle of it. However, I did not see any nebulosity. I checked the Telrad again, and came to the conclusion that the star at the centre of my field of view surely was 52 Cygni. I started using some filters. First the deepsky filter from Lumicon. There was nothing to see. Then the UHC filter, also from Lumicon. I started to detect some nebulosity to one side of the star. Then I tried the Lumicon OIII, and there it was. I could see some parts of the nebula very clearly. I decided to go about 3 degrees to the northeast of 52 Cygni where the brighter, eastern part of the nebula should be. I kept my eye at the eyepiece while moving the telescope. I did not believe my eyes! The eastern part is so very easy with the O-III filter. I could follow NGC 6292-6295 from north to south, all the way. I stayed with this part of the nebula for more than 45 minutes. It got better and better. I will revisit it on the next possible occasion, and try to sketch a part of it. Problem is, my telescope has a true field of view of only 48 arc-minutes. The whole "Cygnus Loop" is 3.4 degrees by 2,7 degrees.

All in all, this was a night to remember. A beautiful object to spend some time on, and the first time my OIII filter (even at a low magnification of 62.5x) made the difference. It was much more effective than all other filters I tried that night. The next time I will try to detect the central parts, NGC 6974, NGC 6979 and Pickering's Triangular Wisp. I can't wait!!!

At 01.10h UT I finally turned the telescope to Mars.

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