We've had a long string of cloudy days these last couple of weeks. Last night it cleared just after sundown, so observed with the 12.5-inch after dinner until about 9pm, then again for another 40 minutes until 10pm. Seeing improved from Pickering 6 to 7, but transparency was below average. There was a lot of dew, and in fact I shut down earlier than I planned because my secondary and even my primary fogged over. I forgot to start the dew heater on the secondary, and the boundary layer fan, which I probably didn't need, was blowing the moist air over the mirror. The last time I had dew on the primary it ruined my coatings; I will need to clean it this weekend.
I started with doubles in Pegasus, then in Pisces. I didn't have my close pair finder charts with me, so I only looked at what was plotted on the CDSA. I noticed there are a lot of carbon stars in this area: yellow, orange, and red stars visible in the 50mm finder and in the scope itself. After my 9pm break I pointed the scope to the "dunce cap" of Perseus, and then moved up to the Double Cluster. The stars looked "wet," and it was here I realized my mirrors were fogging. I started out at 277x but was able to get to 553x after four observations. There was still a fair amount of diffraction and flaring, but I could still make useful observations.
STF 2986: Red A, bluish B, wide separation ~ 2 delta magnitude [6.61, 8.88; 31.2"]
STF 2958: White A and red B; ~2 delta mag, fairly wide separation ~5" [6.63, 9.09; 3.9"]
STT 483 / 52 Peg: Not split. [6.11, 7.27; 0.5"]
STT 536: Not split. [7.0, 7.3; 0.3"]
Sigma / 49 Peg: A bright and white; B very wide and much fainter, to the east [3.9, 10.2; 16"]
STF 2982: A a pretty, bright orange; B widely separated to south, bluish B ~3 delta mag. [5.29, 10.06; 32.6", PA 198°]
STF 2991: Duplicate of STF 2982, even with the colors, but PA is to the north. [5.96, 10.16; 32.5" PA 358°]
A lot of orange stars around here! On 66 Peg now; also orange.
STF 3012 & STF 3021: !! Double double! a delicate sight and such a pleasing surprise. 3012 is near equal brightness ~3" separation. To east is STF 3021, a little wider separation and ~1 delta mag. [3012: 9.47, 9.82; 2.8". 3021: 8.06, 9.26; 8.9"]
STF 3023: very faint star preceeding, about 1" separation. Nearly lost in diffraction. ~2 delta mag. [7.23, 9.11; 1.8"]
74 Peg: Is it the wider separation to the N? [No, not seen; 6.26, 11.3; 91.2" -- too faint, too far away to make the connection]
75 Peg: Very faint, wide separation, pops out with seeing; to south west [AB pair]. Another star to NNE, further away. [5.4, 11.6; 27.5" PA 245°]
STT 504: Orange star with very faint bluish B widely separated to the south. Stills with seeing; 9-10 mag. [7.39, 10.33; 7.6" PA 176°]
STF 3055: Faint yellow-orange A with very small / faint blue B to N, ~3" sep. [7.28, 10.34; 5.5"]
HJ 321: Wide separation but very faint B to south. [6.62, 10.5; 25.3" 135°]
STF 5: Hard white A, very faint but definite small point B to south, 4x fainter. [5.54, 9.44; 7.2" PA 158°]
BU 1093: Very faint, very wide sep to N? [not split: 6.73, 8.55; 0.7" -- separation closer than what I was looking for]
STF 22: A 1803 not seen [0.2" separation]. Saw STF 22 AB,C: near equal white pair, well split, B ~1/2 delta mag, PA to SW. There is also a D and an E pairing with AB, not seen.
STF 12: Yellow and white, ~1 delta mag, PA to S. [6.06, 7.51; 11.5" PA 147°]
STF 36: MCA 1 not seen [0.2"]; but did observe the AB and AC; AD too faint to see. Quintuple system.
STF 27: Orange, with wide separation blue B, PA to NNW, ~3 delta mag. [6.4, 10.3; 29.7" PA 315°]
STT 10: Suspected a very wide separation to W; this seems to be AB [6.46, 10.19 PA 240, 113.6"]. This is a complex system with an AC and a BD. Apparently it is also an optical double :-(
49 Peg: Very wide, much fainter B to east of white A. [3.9, 10.2; 16" PA 83°]
64 Peg / BU 718: Very faint, very small star suspected; hair-split. Flashes in and out with seeing, dances in first diffraction ring. I feel sure of it, it is small, hard, and round; not a diffraction flare. [at 0.4" it would be very tough indeed…hesitant to claim]
72 Peg / BU 720: I saw a small, hard, faint point very tight to A but split. Stays with seeing. [However since this is a <1 D-mag pair, and 0.5" separation, it is very doubtful this is the split. Since what I saw is very similar to my 64 Peg observation, I'd say there was some flare or artifact I was seeing, not the pair.]
In Perseus:
STF 331: Yellow A; B ~1 D-mag. Also looked at anonymous just below this star: orange-yellow with very faint widely separated B, bluish, seen with AV and seeing. [5.21, 6.17; 11.9" PA 85°]
Tau Per / LAB 1 / 18 Per: I noted a very close, much fainter pair; but this is not among the possibilities for this star @ 0.1" separation. Not seen.
STF 314: near equal brightness; A more yellow yellow-white of the two; ~2 disk separation [this is AB,C: 6.95, 7.26; 1.6" PA 317]
Anon. below STF 331: Orange-yellow with very faint, widely separated bluish B, visible with AV and seeing.
STF 307: Orange with faint, bluish, widely separated B. Top of the Perseus dunce cap. [3.76, 8.5; 28.8", 303°]
STF 268: Orange A, faint, wide separated B. Nearly a double-double with STF 272 but my FOV is too narrow. [7.0, 9.66; 21.4" 305°]
STF 270: Tighter, 1 D-mag, white A reddish B. [8.33, 8.36; 1.9" PA 216°]
NGC 957: open cluster near the double cluster: Loose, ~ 20 stars roughly W-E orientation, with one prominent arc of brighter stars.
I looked at the double cluster groups at 101x, and M45 -- which was too large for the FOV but did seem to have nebulosity. I even tried looking at M42, breaking some branches off the apricot tree to do so, but it was still rather low -- the light was diffused by the lattice running along the top of the fence. Patience, it will come.
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