Double Stars Under a Moon Lit Night

[Jiggy 67]

So last night I managed to get clear skies for a couple of hours, from about 7.30pm until around 9.30pm when high cloud rolled in. But I decided to at least make the most of that, and, given the fact there was a full Moon, decided to pick off some double stars from the Cambridge Double Star Atlas so I concentrated on Cassiopeia and Cepheus.

I started with

Dziban. 

Nice double easily split at x58 mag. Primary slightly bigger than secondary which is blueish and dimmer. Secondary at 5 o'clock to primary

Polaris

Bright and large at 8mm (X125 mag) zoom with a faint but obvious much smaller companion at 4 o’clock. I struggled getting Polaris into the centre of the FOV, a peculiarity of goTo  mounts I believe, it just wouldn't get there and the best I could do was to get it in the outer third of the fov!!........anyone able to explain this??

Alfirk 

Beautiful double!! Large bright white primary at 8mm (X125 mag) with a much smaller and fainter secondary at 7 o’clock. Secondary a lovely emerald colour. First clean split of this double at 20mm (X50 mag). Stunning double, my favourite of the night.

Alkurah

White primary with fainter lilac and smaller secondary at 6o’clock. Can separate with 8mm zoom (X125 mag) but better with 4mm Vixen (X250 mag), clear separation. Primary is reported to be a binary but unable to split so increased the magnification using 6mm Vixen plus 2.5 barlow (X416 mag). Not obvious but possible fleeting glimpses of a very close secondary as the seeing fluctuated. I think the best I could do to split the primary was to defocus slightly, when I did this I could see that the primary was itself a double but I could never swear on it

Delta Cep

Nice double, easily split with zoom at 16mm (X62 mag) with a large bright star and a 1/3 size blue companion at 9 o’clock

Sigma Cas

A very tight double, split with the Morpheus 4.5mm (X222 mag). Poor seeing and high cloud which had just started coming in, affected view. Larger white primary and fainter, much smaller star very close at 4 o’clock

That took me till 9.30pm when the high cloud rolled in but really enjoyed the evening. I hope some of the above are doubles that don't immediately spring to mind but I would recommend all of them, just don't panic if you struggle with Polaris and a goto!

 

 

 

Edited December 1, 2020 by Jiggy 67

[domstar]

Great report. I generally look south in the winter because the cold forces me to stay on the balcony so most of these are new to me. I must keep this list to try out when it gets a bit warmer.

[F15Rules]

Nice report, Jiggy👍.

Some interesting pairs there and a nice mix of colour hues.

Regarding Polaris and getting it centred. I don't have goto but I do have an RA drive for tracking..with Polaris only, what I do, and suggest you try, is to forget you have a goto mount..

..turn your mount with your polar axis facing at approximately right angles to Polaris (in either direction).

Then, loosen off both axis clamps and manually point the scope at Polaris..you should now be able to centre the star with your finder, bang in the middle of the finder field, and therefore, if your finder is properly aligned with the main scope, also bang in the centre of your main scope field. Now tighten up both axis locks to hold the position.

Because Polaris is less than 1 degree from the Celestial North Pole, it will stay virtually stationery in, or very close, to the centre of your scope's field of view.

So probably best to look at Polaris either as your first or last target, then for the rest of the session align your polar axis as normal.

Hope that helps😊.

Dave

Edited December 1, 2020 by F15Rules

[Jiggy 67]

Thanks Dave good advice. As it was I could see it in the FOV and I did split it, just couldn’t get it in that centre sweet spot....annoying, but I could try your method next time

[Nicola Hannah Butterfield]

@F15RulesCould you not just be polar aligned and at home position disengage the clutches and rotate the scope manually, then return to home or am I missing something.

@Jiggy 67I haven't done much visual astronomy since the early 90's apart from binocular views, I remember splitting the easy Albireo pair in my 10" Dark Star dob, and going wow, might do some more after reading your report though, once I have a few things sorted.

[Jiggy 67]

26 minutes ago, Nicola Hannah Butterfield said:

Could you not just be polar aligned and at home position disengage the clutches and rotate the scope manually, then return to home or am I missing something.

Yeh, surely that would work as well, though I’d have to try it, can’t work the mechanics out in my head. Wouldn’t involve re polar aligning, just a quick one or two star alignment to get back on track

Go on Nicola, dust off your eyepieces 

Edited December 1, 2020 by Jiggy 67

[Nicola Hannah Butterfield]

14 minutes ago, Jiggy 67 said:

Yeh, surely that would work as well, though I’d have to try it, can’t work the mechanics out in my head. Wouldn’t involve re polar aligning, just a quick one or two star alignment to get back on track

Go on Nicola, dust off your eyepieces 

Someone better able than me might hopefully explain to us both why, but I think it has to do with the meridian being so close that the software can't totally align the mount due north.

dust my eye pieces off, they are only kit e.p. and living in a bortle 7 not the best combination, the Dark Star I had and those lenses everything I saw visually was wow, that was in Stockport in the 90's , D.S 10" I can't remember its focal length, I think this link

it quotes 1,800mm which seems about right as i remember it being as tall as me, and I am 6ft, and the 10" just made it seemed like a canon (though not as heavy) in the old wooden wall ships of the line. Optics were amazing, once I found an object, (the following were viewed from Huddersfield circa 93-94) did see Comet Shoemaker–Levy 9 impact remains with it, and Saturn and m13, tried to find M57 with it to no a vale. Then had to move sell stuff, family ect and only this really had the money to buy a cheap scope hoping to match those days, I can get better at the a.p. side, visually the scope isn't anything like the D.S.