STF2253 AB: 178; 205x: Light orange A and wide 3 delta mag faint B, can just hold direct. Not physical.
17h 58m 22.84s +14° 36' 50.9" P.A. 76.00 sep 11.0 mag 8.52,10.69 Sp M dist. 266.67 pc (869.88 l.y.)
STF2336 AB: 178; 205x: White A and >1 delta mag B, wide. WDS claims physical on the proper motions, but the stars do not share the same parallax range, so they cannot be gravitationally bound.
18h 32m 49.25s +13° 49' 05.8" P.A. 9.00 sep 6.8 mag 9.16,10.23 Sp F0
STF2409 AB: 178; 333x: Very nice, 2 delta, very finely split pair, excellent. WDS uncertain, and unfortunately no Gaia data for the B star.
18h 51m 43.74s +13° 31' 06.9" P.A. 22.00 sep 0.9 mag 8.46,9.64 Sp G5 dist. 261.1 pc (851.71 l.y.)
STF2411 AB: 178; 205x: Bright light yellow and 3 delta bluish B, wide. In a rich field. WDS uncertain but the Gaia data looks promising: 9% parallax range overlap, 1,913 AU separation, higher mass 2.74/1.24, and the radial velocity delta is *just* less than the escape velocity.
18h 52m 18.63s +14° 32' 08.0" P.A. 95.00 sep 13.3 mag 6.63,9.61 Sp G9III dist. 111.11 pc (362.44 l.y.)
STF2412 AB: 178; 205x: Nice! Very fine near equal pair, <2". WDS uncertain, but the Gaia data seems good: 40% parallax range overlap, 491 AU separation, high stellar mass 2.48/2.49, so they are likely gravitationally bound.
18h 52m 35.04s +14° 00' 12.2" P.A. 57.00 sep 1.4 mag 8.96,9.03 Sp K2
STF2206 AB: 178; 205x: Pretty difficult, barest of splits with 205x and very noticeable delta mag. Seeing is not good so there are worse star images higher powers. WDS uncertain, but the stars do not share the same parallax ranges, -30%, so not gravitationally bound.
17h 44m 32.13s +18° 59' 31.8" P.A. 248.00 sep 0.9 mag 8.83,9.82 Sp B9 dist. 584.8 pc (1907.62 l.y.)
KU 56 AB: 508; 205x: <1 delta mag, well split. Not physical.
17h 53m 17.67s +19° 03' 37.4" P.A. 127.00 sep 2.9 mag 10.21,10.90 Sp A2
HO 562 AB: 178; 205x: Fine faint pair, well separated, half delta mag. WDS physical, and the Gaia data confirms: 49% parallax range overlap, 994 AU separation, 1.46/1.26 stellar mass, and the radial velocity delta is less than the escape velocity.
17h 53m 22.77s +20° 55' 32.1" P.A. 257.00 sep 3.6 mag 10.53,11.10
HU 320 AB: 178; 205x: Very faint close pair, can just hold direct. WDS uncertain, however the stars do not share the same parallax range.
18h 28m 39.80s +16° 13' 42.5" P.A. 144.00 sep 2.0 mag 10.41,10.85 Sp F8 dist. 110.62 pc (360.84 l.y.)
MIL 5 AB: 178; 205x: Fine faint close pair, 3", <2 delta mag. WDS uncertain, but the two stars do not share the same parallax range.
18h 39m 25.51s +15° 39' 32.9" P.A. 58.00 sep 3.2 mag 10.07,10.69 Sp G5IV dist. 72.78 pc (237.41 l.y.)
STF2400 AB: 178; 205x: White and 2 delta mag wide B, in a rich field. Not physical.
18h 48m 54.88s +16° 15' 24.4" P.A. 159.00 sep 9.7 mag 8.08,11.10 Sp G0 dist. 128.7 pc (419.82 l.y.)
HU 328 AB: 178; 205x: AD Her. 1 delta faint B noticed with averted vision, but can then hold direct. Well separated. WDS uncertain, however there is 27% parallax range overlap, 2,583 AU separation, and 2.54/2.01 stellar mass, so they are likely gravitationally bound.
18h 50m 00.30s +20° 43' 16.5" P.A. 187.00 sep 4.8 mag 9.76,11.16 Sp A4V+K2 dist. 1149.43 pc (3749.44 l.y.)
STF2182 AB: 178; 205x: Pretty faint, 1 delta mag, wide. WDS physical, and there is 8% parallax range overlap, 1,021 AU weighted separation, and 1.69/1.36 stellar mass, so they likely are.
17h 32m 27.74s +23° 52' 04.3" P.A. 1.00 sep 5.3 mag 9.06,9.96 Sp G0
HU 1285 AB: 508; 533x: Hairline split at 445x, better split at 533x and 667x. White, slightly unequal. Physical with an 825-year period, it will make a very rapid periastron pass over the next couple of decades and appear on the opposite side, so it is worth watching.
17h 43m 38.76s +22° 36' 43.2" P.A. 209.60 sep 0.5 mag 8.88,9.17 Sp F5 dist. 156.74 pc (511.29 l.y.)
17h 35m 14.42s +25° 45' 21.9" P.A. 104.00 sep 7.8 mag 9.93,10.48 Sp G5
STF2364 AB: 178; 205x: Pretty white stars, 2 delta mag wide B. WDS physical, however the stars do not share the same parallax range, -73%, so they are not gravitationally bound.
18h 40m 05.13s +24° 42' 12.4" P.A. 174.00 sep 10.6 mag 8.09,10.32 Sp K0 dist. 129.53 pc (422.53 l.y.)
HO 416 AB: 178; 205x: B just seen with direct vision, well split, 2 delta, light orange stars. Not physical.
17h 27m 46.17s +30° 23' 43.7" P.A. 98.00 sep 4.5 mag 8.85,10.60 Sp F5
STF2174 AB: 178; 205x: Faint stars for a Struve, unequal 1 delta mag, fairly wide. WDS uncertain, but the stars do not share the same parallax range, -22%, so not physical. In the same field as STF2175.
17h 29m 25.08s +32° 45' 51.8" P.A. 331.00 sep 5.4 mag 11.13,12.40
STF2175 AB: 178; 205x: Blue-white A and bluish B, wide, 2 delta mag. In the same field as STF2174. WDS physical, and while there is a 100% parallax range overlap, 3,460 AU separation, 2.10/1.37 stellar mass, the radial velocity difference (6.33) far exceeds the escape velocity (1.33), so these are not or will not remain gravitationally bound.
17h 29m 26.85s +32° 42' 33.8" P.A. 9.00 sep 13.3 mag 8.79,10.64 Sp F3+F7 dist. 131.58 pc (429.21 l.y.)
Europa was occulted by Ganymede. Europa had reached the apastron of its orbit and had apparently slowed to a standstill, allowing Ganymede to overtake it. When I started my observation with the 6-inch, they appeared as a squat snowman, with one of the moons being smaller than the other. I could also perceive a slight color difference, with the smaller moon being more orange. As time passed the elongation shifted to the side, and the notch between them grew stronger, until there was a hairline and then a good clean split -- a clear lateral movement. Once separated the size difference was very apparent, with the smaller (Europa, 970 mile radius) about half the size of the other (Ganymede, 1,637 mile radius). I don't recall seeing an occultation of two moons, so this was really neat to see.
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