5 february 2021

Transparency and seeing were slightly better last night.  Between 8-9pm I used the Tour function on the Argo Navis to sample some doubles in Orion.  Some lovely pairs but I didn't bother to take notes on them.  After 9pm I observed a little higher up, mostly in Gemini.  I went to full aperture though with the apodising mask, and had to keep the magnifications low.  All the same, a good session.  Some dew, and it got cold, in the lower 40s.

BU 1059 BC: 508; 333x: A-BC is the very bright orange A star Mu Gem, which is itself a  with several faint widely separated stars around, the brightest of which is BC.  BC was quite faint, flashing a definite elongation but no separation with averted vision, significant delta mag.   Discovered in 1889 36-inch at 0.8", it has narrowed since.

06h 23m 02.65s +22° 29' 24.4" P.A. 265.00 sep 0.6 mag 11.50,12.40

OSB 3 AB: 508; 333x: Extremely faint B, approximately 2 delta mag.  B see with averted vision only, well separated.  It is a physical pair.  W.H. Osborn, who has eight discoveries to his name, about whom I can't find any further information (I assume he is not the railroad tycoon in the Google search results).
06h 22m 23.33s +22° 43' 07.4" P.A. 4.00 sep 7.9 mag 9.80,11.00

STT 519 AB: 508; 205x: Pretty 2 delta mag, wide, light yellow A and very light blue B.  Physical
06h 31m 17.74s +15° 44' 14.4" P.A. 78.00 sep 8.4 mag 8.36,10.90 Sp G5

J 1093 AB: 508; 333x:  Tough near equal pair, I have trouble to resolve the elongation which appears in all powers through 533x, though can tell this is double
06h 34m 43.85s +26° 05' 20.7" P.A. 4.00 sep 1.3 mag 9.77,10.50

VDK 1 AB: 508; 205x: Attractive pair, approximately 2 delta and 3", slightly light orange A, well split.  Sadly not physical.  One of three discoveries by J. Vanderdonck
06h 36m 29.25s +26° 43' 39.5" P.A. 43.00 sep 3.0 mag 10.30,11.40

STF 943 AB: 508; 205x: Not sure why this one was picked out as a double, it's such a rich field any could be any such pair.  Wide near equal white. 
06h 37m 47.00s +23° 10' 36.0" P.A. 135.00 sep 31.1 mag 9.17,9.42 Sp G0

A 511 AB: 508; 205x: Wonderfully close pair, looks like the small snowman's head popped off the body, close split, 1 delta mag, white stars 

06h 44m 20.42s +28° 22' 08.1" P.A. 157.00 sep 1.6 mag 9.63,10.43 Sp F8 dist. 167.79 pc (547.33 l.y.)

A 122 AB: 508; 533x: Nice light orange stars, hairline split with indifferent seeing, PA to the SW.  Slight magnitude difference.  Physical with 102.3-year period, I have the PA reversed in my estimate, it's to the NE -- still can claim it though.  It is coming off apastron and will close slightly in the next 20 years.  Aiken discovered in 1900 with the Lick 36-inch also at 0.4" -- 118 years since, so it has made a little more than one revolution.

06h 45m 27.02s +29° 21' 59.8" P.A. 22.00 sep 0.4 mag 8.89,9.39 Sp F8V dist. 77.04 pc (251.3 l.y.)

WFC 42 AB: 508; 205x: White stars, wide split, very slight delta mag, quite pretty.  Physical pair.
06h 45m 27.48s +33° 12' 55.4" P.A. 358.00 sep 4.5 mag 10.11,10.80

STF 981 AB: 508; 333x: Very finely split, white stars, nearly 1 delta mag.  Appeared as a rod at 205x.  Physical with a 1089.7-year period.  Discovered in 1831 at 3.7", near apastron, it has narrowed considerably since.
06h 55m 28.54s +30° 09' 42.3" P.A. 115.80 sep 0.9 mag 8.72,8.97 Sp G0 dist. 38.49 pc (125.55 l.y.)

STF 983 AB: 508; 205x: B is very faint for a Struve pair, it's wide, with a light orange A star, approximately 3 delta mag.  Not physical.

06h 56m 13.67s +34° 27' 32.7" P.A. 36.00 sep 10.7 mag 8.70,12.70 Sp B9

STF 984 AB: 508; 205x: This is a typical Struve, light yellow A, slightly orange B, approximately one delta mag and 4".  Not physical 

06h 56m 16.59s +32° 26' 41.4" P.A. 155.00 sep 3.3 mag 8.67,10.80 Sp G5