STF 2010 (H V 8) in Hercules
I love to observe double stars, and one of my favourite lists is to observe is the Herschel 500 by Bruce MacEvoy. On the night of the 12th of June 2021, around 23:30 local time (Landgraaf, Netherlands), I observed Marsic, a beautiful and colourful double star in Herculis, with my 150mm Newtonian. Marsic has a separation of 27" and a position angle of 159 degrees. The view was at its best in the 25mm Zeiss eyepiece, with a magnification of 30x and a 1.7 degree field of view (approx). The magnitude 5.1 A-component looked definitely yellow. The magnitude 6.2 B companion looked yellowish as well, but with 3mm at 250x I found it more orange, especially when I slightly turned the view out of focus. It's colour was somehow deeper at this magnification. I also noticed a trapezium-like or keystone-like asterism to the north of the double. A very pretty view.
The sketch below was made with pencil and paper at the telescope, and later processed with Affinity Photo. South is up and west is to the left.
Double stars: Alpha Ursa Majoris
On the 26th of april 2020 I observed four double stars in Ursa Major. My favorite for the night was Alpha Uma, a very special binocular double. The mag. 2 A-component has a yellow orange colour, which contrasts beautifully with the mag. 7 blue white B-component. The stars have a separation of 381", so it is very wide. There are lots of weaker stars in the field, and I think the limiting mag is about 9.4. The view is very pretty!
The observation was made with a Fujinon 10x70 (fov 5.3 degrees), mounted on a mirror mount (north/south is flipped) Seeing and transparency good, very stable conditions. No clouds. South is up and west is to the right. The sketch is made with pencil, and later processed with Affinity Photo.