Monday, 24 August 2009

Observing session 19th August 2009

Another clear night! Sadly it will have to be another short session due to work in the morning (and I'd already overslept this morning as it was!). So, another binocular session.

Clear, but transparency not as good as previous night due to contrails from jets passing overhead. The Isle of Wight sits directly below the approach paths to Heathrow, Gatwick and other major airports plus transAtlantic traffic originating on the Continent (I assume that some Continental European traffic for eastern China and Japan also go over here as these routes often go over the North Pole). Can't very well complain though as I - wanting to get out of the UK as often as humanly possible! - do a fair bit of flying myself! The contrails do dissapate quite quickly.
Warmer than previous night: 14 degrees C. Humidity 80%. No wind. Steady seeing.
Instrument used: 8x42 Leica binoculars.

Collinder 399: Open cluster (or asterism?) in Vulpecula
The famous Coathanger, and looks exactly like an upside down coat hanger. Through the binoculars I can see 11 stars, all bright ones, with 6 in the bar and another 5 in the hook. The hook contains the brightest stars, two of which are around a magnitude brighter than the others. Observation interfered with by jet trails.

Tried to observe NGC 6934, a globular cluster in Delphinus but a vapour trail was sat right over it. One for later.

NGC 6709: Open cluster in Aquila
Easily found to SW of Zeta and Epsilon Aquilae. Fairly large roundish o.c. hazy with direct vision but some stars resolved with direct vision. Will observe this with scope at some point.

NGC 6934: Globular cluster in Delphinus
Now the contrail has cleared I could have a go at this g.c. It wasn't that hard to find but not very easy to see. It looks like a round, fuzzy, fat star in the 8x42s.

NGC 6716: Open cluster in Sagittarius
This was easy to find (along with neighbouring Cr 394), despite its low altitude. Large and with some members seen. It would undoubtedly be miles better from a more southerly location, such as southern Europe.

NGC 6520: Open cluster in Sagittarius
Not a chance. Far too low in the murk. Will try earlier tomorrow night if clear.

NGC 6633: Open cluster in Ophiuchus
Very easily found near IC 4756 (itself easy to see and also on the challenge list). Triangular, rich and very bright. Many stars resolved. Nebulous background which means many more should be seen in a scope.

IC 4756: Open cluster in Ophiuchus
Huge o.c. Next to NGC 6633. Irregular. Very large and rich. many stars seen with both averted and direct vision. Impressive. Can't wait to get sorted with big scope and get that onto it!

IC 4665: Open cluster in Ophiuchus
Very easy to find. Large, splashy o.c. near Beta Ophiuchi (Cebalrai). Irregular. Many bright stars visible with averted vision and even a dozen or so easily seen directly.

The following night (20th) I went out early, as it was getting dark, to try for NGC 6520 which I'd failed to see on the 19th as I'd left it too late in the session and it was too low to be seen, lost in the murk. Well, I did eventually see it, here's the observation:

NGC 6520: Open cluster in Sagittarius
Only just seen, after a time for my eyes to adjust and it was ridiculously faint due to low altitude and atmospheric pollutants. A small patch barely visible against background sky. No stars resolved. Will have to have another bash at this one next year, earlier in the year when Sagittarius is as high as it gets in the UK sky.
This has to go down as the shortest observing session ever due to tiredness, the need to go to work in the morning and a fair bit of drifting cloud!

These observations over the past evenings take care of the summer set of AL Deep Sky Binocular objects. The rest I will do during the autumn and winter.


Should hopefully be sorted out on the scope front this week...