20 january 2021

 Last night was both rewarding and frustrating.  I started observing at around 7:30, and the seeing was quite good.  The moon was in quarter phase so I spent a good hour on it with binoviewers at around 300x at full aperture and a light red filter.  Quite amazing detail all around.  My first sighting of Linne, and fine views of Hyginus Rille, Trisnecker Rille, and more.  

I decided to switch over to double stars, and went straight for short period pairs: 

BU 1052 AB: 508; 533x: Suspected at 333x, split at 533x, light orange stars, ~1.5 delta, it was actually an easy split and I could easily place the PA to the south, which is just where it is. 105.692-year period, it is near apastron and won't make significant change in my lifetime.  Discovered with the 36-inch at 0.7" in 1889, it has made just over one revolution since.
05h 41m 40.34s -02° 53' 47.3" P.A. 183.10 sep 0.7 mag 6.68,8.22 Sp A9IV-V dist. 80.71 pc (263.28 l.y.)

STT 65 AB: 203; 533x: For this one I chose to use the 8-inch mask, since the star brightness washed out the image in full aperture.  This appeared as a very tight pair, hairline split, and ~1 delta mag.  I estimated the PA to the south.  Approaching apastron, and won't make significant change in my lifetime in spite of the 61.2-year period.

03h 50m 18.91s +25° 34' 46.7" P.A. 202.60 sep 0.6 mag 5.73,6.52 Sp A2V+A5V dist. 56.47 pc (184.21 l.y.)

BU 524 AB: 508; 1067x: This one I suspected elongation at 667x and it was better seen at 1067x.  I estimated the PA on an E-W line, though it was tough to tell which was B.  This is a component of STF 318.  It is currently at apastron and again, won't make a significant change in the coming years.  31.63 year period.  Discovered with the 18.5-inch, Burnham says: "It is at all times a difficult pair, and the motion is rapid.  It is now known to be one of the most interesting binaries in the heavens.  The distance never much exceeds 0.2", so that it is always a difficult pair, and beyond the reach of most telescopes."

02h 53m 42.58s +38° 20' 15.6" P.A. 266.10 sep 0.2 mag 5.79,6.80 Sp F4IV dist. 70.67 pc (230.53 l.y.)

I attempted COU 2031, but I find my PA estimation was off though I thought I saw a peanut shape.

04h 46m 26.92s +42° 20' 54.2" P.A. 150.00 sep 0.2 mag 6.90,7.80 Sp G0 dist. 67.07 pc (218.78 l.y.)

Seeing began to degrade at around 10pm, and I was also having pointing accuracy problems -- which is why I have no more pairs to report.  I had a quick look at M42 and the "37" cluster, but wrapped up early.