20 march 2021

I think the lesson is to always go out.  Last night's forecast was for average seeing, which usually means crummy views.  And there was some wind, and there was some haze, which showed itself as a glow around the moon.  Nevertheless I had a pretty good couple of hours with some interesting, and even some short period, pair seen.

First I need to mention my great surprise at a Celestron zoom eyepiece I bought.  It was an old model, apparently never used, made in Japan.  I wasn't expecting much, but I wanted to try a zoom at the right magnification range I typically use for most of my double star observing.  This one ranges from 18mm to 6.5mm, or 148x, 222x, 296x, 410x.  I first looked at the moon and was shocked how crisp the view was, great contrast, and how even at the highest magnification it seemed to beat the seeing -- maybe because of the narrow field of view.  I didn't mind the more restrictive FOV.  I felt I was seeing more than what I would even in my Ethos, again maybe because the FOV made me concentrate -- but I think the qualities of the eyepiece are more suited to lunar.

Next I tried Mars, and I could see the polar ice caps and some dark markings -- and Mars was very close to a bright orange star, it looked like a much magnified view of a double star.

I then tried M42, and here is where my surprise really solidified.  Not only could I see E & F, and much ripple in the nebula, but also a string of five very faint stars embedded in the nebula -- not within the Trapezium but above it.  I had never seen that before.  On bright stars the flaring and diffraction is much smaller than in my Ethos.  I wonder why?  And the 18mm was enough to be a finder setting so long as the pointing is accurate.  In any case I'm shopping for a barlow to go with this since I think this eyepiece will be my go-to from now on.  It was very convenient not to switch between them while viewing.

COU 47 AB: 178; 410x: Elongated at lower magnifications, strongly notched at 410x, noticeable magnitude difference.  Same proper motions so likely physical.
08h 39m 42.78s +20° 05' 10.4" P.A. 141.00 sep 0.6 mag 7.93,9.58 Sp A7IV

BU 584 AB: 178; 410x: I can't believe I got this, very faint B about 1" separation, can just see it direct vision, brightens with averted, very faint.  This star the faintest of a prominent long triangle of stars.  Component of S 571, which has several other widely separated pairs.  In Praesepe, but I neglected to check my finderscope.

08h 39m 56.49s +19° 33' 10.7" P.A. 290.00 sep 0.9 mag 7.31,12.30 Sp Am

 

KU 32 AB: 178; 148x: Very fine, wow quite amazing, around 2", split nicely, 3 delta magnitude.  The faint B star disappears with increased magnification.
08h 41m 18.40s +19° 15' 39.6" P.A. 165.00 sep 2.2 mag 8.06,10.24 Sp A8V

STF1262 AB: 178; 148x: Well split, a bit less than 2 delta mag, white stars
08h 41m 58.04s +23° 47' 56.0" P.A. 203.00 sep 6.9 mag 8.54,10.09 Sp K0 dist. 645.16 pc (2104.51 l.y.)

J 1110 AB: 178; 148x: Well split white stars, about 1 delta.  Physical
08h 42m 06.27s +25° 00' 43.4" P.A. 42.00 sep 3.4 mag 9.92,10.24

STF1276 AB: 178; 148x: Wide, white, near equal stars, nice.
08h 47m 10.99s +11° 09' 34.2" P.A. 353.00 sep 12.7 mag 8.32,8.56 Sp A0 dist. 980.39 pc (3198.03 l.y.)

VDK 3 AB: 508; 410x: With apodising mask.  A surprise short period find.  Light orange stars -- they are carbon, HP Cnc.  About 1 delta mag, more than 1" separation.  Seeing is bloating the stars a bit, but can recorded the PA by drift, it follows a S-N line.  J. Vanderdonck, who has three discoveries to his name in the WDS.  Physical with a 223.9709-year period, it will make a quarter turn by 2040.

08h 50m 42.33s +07° 51' 52.4" P.A. 195.10 sep 1.1 mag 9.91,10.09 Sp K0V dist. 23.09 pc (75.32 l.y.)

PER 1 AB: 508; 410x: Quite a beautiful pair, light yellow stars, >1 delta mag, about 1", emerges to view with seeing, quite good.  One of two J. Perrotin discoveries.  Same proper motions so will likely prove to be physical.
08h 51m 13.71s +08° 20' 18.6" P.A. 350.00 sep 0.8 mag 8.30,9.59 Sp K0

STT 195 AB: 508; 148x: White stars, wide, one delta
08h 53m 57.80s +08° 25' 17.7" P.A. 138.00 sep 9.8 mag 7.73,8.33 Sp F8 dist. 1315.79 pc (4292.11 l.y.)

AG 338 AB: 508; 148x: IK Cnc. White stars, near equal, well split.  Physical with a 1790-year period.  A is TOK 196 0.2", not attempted, with just a 15-year period, need to go back!
08h 54m 41.52s +16° 36' 39.7" P.A. 166.30 sep 2.1 mag 9.01,9.22 Sp G5 dist. 40.14 pc (130.94 l.y.)

A 2968 AB: 508; 222x: Very fine pair of white stars, <1", split with 410x but then backed off magnification and could still split with lower.  

08h 57m 06.22s +10° 45' 29.1" P.A. 132.00 sep 1.2 mag 9.07,9.42 Sp F5 dist. 571.43 pc (1864 l.y.)

ALD 115 AB: 508; 222x: Fine pair, light orange stars, with seeing

09h 00m 12.88s +15° 49' 30.8" P.A. 270.00 sep 1.6 mag 10.60,11.20 Sp K7

STF1297 AB: 508; 148x: Nice easy wide Struve, 1 delta mag, physical
09h 00m 32.70s +22° 43' 36.7" P.A. 159.00 sep 5.1 mag 8.88,9.96 Sp G5 dist. 166.39 pc (542.76 l.y.)

HO 360 AB: 508; 222x: Faint B easily seen, widely separated from bright white A
09h 00m 29.99s +22° 28' 08.0" P.A. 156.00 sep 3.9 mag 8.41,12.10 Sp F7V dist. 80.26 pc (261.81 l.y.)

STF1300 AB: 508; 148x: Very light orange stars, one more white than the other, well separated, near equal.  Physical with 878-year period
09h 01m 17.48s +15° 15' 56.8" P.A. 178.50 sep 5.0 mag 9.47,9.73 Sp M0V:p dist. 15.97 pc (52.09 l.y.)

STF1327 AB: 508; 148x: White A star and much fainter B, with another further out wide (AC).  Not physical.
09h 15m 32.67s +27° 54' 53.4" P.A. 32.00 sep 5.3 mag 8.78,10.32 Sp F8 dist. 146.2 pc (476.9 l.y.)

HO 43 AB: 508; 410x:  Fine white stars, not quite 1 delta mag, very nice clean split.  Wow.  Physical with 358.6-year period, it will widen a couple tenths in the next 20 years

09h 18m 36.25s +20° 48' 49.4" P.A. 94.50 sep 0.6 mag 9.31,9.46 Sp F5 dist. 108.11 pc (352.65 l.y.)