Doubles - Endlessly Challenging!

[cloudsweeper]

4.20pm, Wednesday, cold, clear sky, slim crescent Moon, waxing, low in the south. Aligned the GoTo 8SE on it.

Mare Crisium – split down the middle by the terminator. Tetyaev and Harker Ridges to the east, x169, and some hilly features east of their junction. Some “shimmering”.

4.45pm – noticed Jupiter above Luna and a bit east. Two moons each, side, all on a 45deg line. Two Jupiterean belts, very pale. x169.

Now for the Aquarian doubles (new ones for me):

Ʃ2988 – 7.9 and 8.0 mags, 3.5” separation. x102, a clear, close split, matched, side by side, sparse field.

107Aqr - 5^th and 6^th mags, 6.6”. x102 again, good split, fair match, secondary at 4 o'clock, sparse field.

53Aqr - 6^th mag pair, much tighter at 1.3”. No success here, losing sharpness above x200.

Ʃ2936 - 7^th and 9^th mags, 4.2”. GoTo still good, target confirmed by a “vertical” line of three stars to south. Needed a bit more magnification because of the faintness of the secondary. Thought I got it at x 135, secondary at 1 o'clock. At x145, sec. was clearer in moments of good seeing. Even seemingly easy doubles can pose a bit of a challenge! And using several EPs can be useful to push the mag without falling foul of the seeing.

Finished with a quick look at M45 Pleiades cluster in the east.

Almost 2 hours of pleasure, and still early, so in for a meal (and a little wine).

Doug.

[MylesGibson]

That's a productive night! Nicely done!

[cloudsweeper]

2 hours ago, MylesGibson said:

That's a productive night! Nicely done!

Thanks for the response Myles, much appreciated!

Much as I like GoTo for ease and tracking, I must say the extra aperture with the 10" Dob really helps to raise the mag when the seeing is poor.  So that'll be my choice next time out!

Doug.

[Jiggy 67]

Nice report, doubles can be challenging indeed and not just the separation. I was observing Xi Cephai in Aries the other night, a lovely double star with a bright white star and a blue companion close by , they look beautiful together……however it’s actually a triple with a third star further away from the B component, only problem was that the third star is 12th magnitude and I just couldn’t see it

[Mr Spock]

Some nice doubles there. I had a Pegasus session planned, scope was out, had some great views of Jupiter before dinner, but the sky went really milky after that. I could only see stars above mag 3. So I brought the scope in.

[cloudsweeper]

1 hour ago, Jiggy 67 said:

Nice report, doubles can be challenging indeed and not just the separation. I was observing Xi Cephai in Aries the other night, a lovely double star with a bright white star and a blue companion close by , they look beautiful together……however it’s actually a triple with a third star further away from the B component, only problem was that the third star is 12th magnitude and I just couldn’t see it

Thanks Jiggy.  Yes, Xi Cep is a nice double.  The C star is mag 12.6, so it's not surprising it didn't show up.  Also, it's not a true physical component, but of course not all doubles are gravitationally bound, and they're still good to track down and observe!

Doug.

[NGC 1502]

To anyone reading this who struggles with the false concept that observing from town is dire-

Try double and multiple stars. The whole sky is stuffed with them at every season. Even in high summer when it doesn’t get fully dark from your location, or if a bright moon is up, or your town is plagued by light pollution, or……..

Doubles are one class of objects that are least affected by the issues above. They vary from being visible in binoculars to the other end of the scale of needing a premium scope with rare steady skies and a big challenge like Sirius B. Most are in between those extremes.  And the science behind doubles and multiples will satisfy armchair astronomers too.

What’s not to like👍………Ed.

[cloudsweeper]

23 hours ago, NGC 1502 said:

To anyone reading this who struggles with the false concept that observing from town is dire-

Try double and multiple stars. The whole sky is stuffed with them at every season. Even in high summer when it doesn’t get fully dark from your location, or if a bright moon is up, or your town is plagued by light pollution, or……..

Doubles are one class of objects that are least affected by the issues above. They vary from being visible in binoculars to the other end of the scale of needing a premium scope with rare steady skies and a big challenge like Sirius B. Most are in between those extremes.  And the science behind doubles and multiples will satisfy armchair astronomers too.

What’s not to like👍………Ed.

Good encouragement Ed!  Great targets in terms of properties, colour, setting, etc., AND also have the bonus of often presenting a challenge in terms of locating and splitting, so they are certainly not just a boring "doddle".  (Must admit, that was my first thought when I heard about doubles.  How wrong can you be?!)

Doug.

 

Edited January 10, 2022 by cloudsweeper