A clear night (with the odd band of Cirrus cloud) on the 21st brought out the 8” SCT for an observing session in Hercules. All targets where plotted in Uranometria, red light on, comfy stool set up, and no dew; but I did have a force 4 wind making the scope shake a little at times.
First target was a star I had done a few years ago. OΣ329 HERCULES. A wide pair with 33” between A and B, which made it an easy one to start with.
Not too far away was another binary I had observed a year or two ago, namely GUI 17 HERCULES. An even wider pairing with 76.1” being a good thing as the 12.1mv secondary was far enough away from the ‘bright’ 8.1 magnitude primary to be plainly visible at 203x.
I turned to Σ2161 HERCULES. A nice tight pair at 1.3” separation and 9.3/9.5 the magnitude difference. The seeing was becoming average and the stars where ‘boiling’ over a certain magnification. I could just split this system at 203x, but a better view was attained at 270x. When I dropped in my 6mm orthoscopic eyepiece the image was a complete mess, so 270x seemed to be the limit on this pair.
Not too far away lies CBL 67 HERCULES. By this time the bands of Cirrus clouds where becoming spread out across the sky and I was having to wait until a clear slot appeared. After much straining and during a clear period, ‘B’ at magnitude 12.8mv popped into view at 406x. At that magnification the image was degraded but the secondary was seen and held with direct vision.
Next plotted target was SKF 2822 HERCULES. A bright pair of 8.3 and 9.2 magnitude stars with a gap of 89.3”. So no need for high power and a spoilt view.
Finally a surprise.
I had one final star plotted in my atlas for tonight, but with the seeing steadily becoming worst, I never really expected to split this one. I thought with the separation being 0.9”, this was not going to be achievable.
I turned the scope to 69 HERCULES. 4.8 and 8.5, and 0.9”. I had nothing at 135x and 203x. But dropping the Barlow in and cranking up to 270x showed a possible secondary in the correct position of 140°. In moments of steady seeing, ‘B’ sprang into view and vanished again as the brighter primary smudged and blocked it out. But when the sky permitted, the secondary was just sat there for all to see. I even manged to get a good view with the 6mm which gives me 338x. I held ‘B’ in brief moments when the atmosphere complied, and that gave me a great view of a star I did not expect to split on this mediocre night.
After that, feeling quite content and satisfied, I packed away for the night as the clouds began to obscure the stars.
I love nights like this.
Clear skies all.