Monday, 24 August 2009

Observing session 18th August 2009

This was a good clear night with steady seeing and decent transparency with good contrast in the Milky Way. The visual limiting mag was 6.5. The temperature was 12C with high humidity of 80% - the price of summer in the UK. Instrument: 8x42 Leica binoculars.
I used my 8x42 binoculars instead of either of my two small scopes, mainly because the refractor can't be comfortably used at high declinations and the little Meade SCT has no decent tripod (it's a disaster on a photo tripod because I don't own a tripod that is up to the job) and also it was a perfect opportunity to make inroads into the AL Deep Sky Binocular certificate I am doing.

My observations are as follows:

NGC 6819: Open cluster in Cygnus
One clump of stars among many in this very rich region. Some stars resolved, around 5 or 6.

NGC 7063: Open cluster in Cygnus
Very easy to find as it is stuck out by the lower (eastern) wing of Cygnus. With direct vision it is an irregularly roundish misty patch easily seen against the background sky. Detached. With averted vision around 8 or 9 stars can be seen. Large.

NGC 7789: Open cluster in Cassiopeia
Huge open cluster just east of Beta Cygni. Large, detached and - while not faint - not overly bright. Roundish and nebulous looking. With averted vision it looks a bit granular, but not resolved fully.

NGC 6940: Open cluster in Vulpecula.
Absolutely huge o.c. looking, through the 8x42s like a detached portion of the Milky way. It has an oval shape. Nebulous but with some brighter foreground stars.

NGC 6823: Open cluster in Vulpecula
This was much more of a challenge than the previous ones. This is another of 'one clump among many' situations you get with binocular observations of Milky Way open clusters, but I eventually found it. It is near the (easily seen) Dumbell Nebula and looks like an irregular clump of stars. A pretty big cluster, although smaller than some of the other targets this evening. Some members resolved.

By then it was gone midnight and I had to get up for work the next morning. A good session.