15.12.17 Double stars observing report

[Doc]

15th December 2017

Back garden
19.00-23.45
Skywatcher 120ED Esprit
Very cold and clear
Limiting magnitude was 4.4

Cepheus

Beta Cep - Mag 3.2/8.6 - 14" Sep - This was easily split using the 12mm Clave giving x70 mag - Components looked white/white.
STF2883 - Mag 5.6/8.6 - 15" Sep - Easily split using the 12mm or 16mm Clave - Components looked white/white. Could not pick out Argle45 which is in the same field of view of STF2883.
Next I found Mu Cep also known as the Garnet star, this is an lovely red star but to me looked more an orange colour. the star lies on the border of IC1396, embedded in the centre of the Elephant trunk nebula is the double star STF2816. This turned out to be a lovely triple star the main star being mag 5.7 and having a yellow hint, the other two being mag 7.5 and white in colour. The seperation was roughly 12" and 20". The Clave 12mm split them lovely.
Staying within IC1396 I found STF2819 another wonderful double at mag 7.4/8.6 and with a seperation of 13". I could fit STF2819 and STF2816 all into the same FOV of the 20mm Clave and observe all five components. This is is a wonderful system to view and I spent sometime trying different eyepieces.
STF2863 was next and this was easily split using the 12mm Clave at x70. The mags were 4.5/6.4 and had a seperation of 8.1". They appeared white/white.
STF2923 was next and this was really easy, I could split this even with the 20mm Clave at x42. They appeared white/white.

Cygnus

Started of with the best and of course this is Beta Cygni or Albireo. We all know this double star so all I will say is magnificent.
Then onto a very wide and very famous triple which is 31 Cygni also known as Omicron1. The mags are 3.9/7/4.8 and a seperation of 111" and 333". This is a great triple and the colours were yellow for the main and maybe blueish white for the companions. Easily split in the 12mm Clave.
Next over to 61 Cygni and I was greeted with a wonderful pair of stars with a seperation of 31" and mags of about 5.2/6.1. I could detect that both had a yellow tint to them. Easily split in the 12mm Clave. They looked lie a pair of eyes staring at you.
Next I tried a tough one, this was Tau Cygni - Mag 4/6 - seperation 1". With the 4.5mm Delos inserted in the focuser I couldn't detect any split.
Psi Cygni was next, this took some splitting but I did manage it, the seperation is 3". Mags are 5.0/7.5. Colours seemed very muted but I would say Orange/white.
Delta Cygni next and this was a very tricky split but you could just make it out with averted vision lying just outside the first diffraction ring. Mags are 2.8/6.2. Split using the 6mm Delos at x142.

Aries

Gamma Aries - Mag 4.5/4.8 - Easy split with the 12mm Clave, both looked white with maybe a blue tinge.
Pi Aries - Mag 5/9 - sep 3" -Quite a difficult split and it needed the 6mm delos to do it justice.
30 Aries - Mag 6.5/7.5 - sep 40" - A wide double which made an easy split, colours looked yellow and white.
1 Aries - 6.2/7.2 - sep 2.8" - Difficult one but did manage a peanut split with the 6mm Delos.
Lambda Aries - Mag 4.9/7.5 - 37" - I got this one confused with 1 Aries first of all as I read the wrong seperation info and they are very close together but eventually I found out which one was which. Easy split looked yellow and blue.
About 3 degrees north of Hamal there is an arc of three stars known as 10 ,11, and 14 Aries, the latter 14 Ari is a wonderful triple star. The main star shines a lovely gold/yellow colour and you then notice it's two dimmer companions that look white, fantastic in the 12mm Clave. Mags 5/8/8 - 93"/105".
In the same FOV was 10 Aries another triple but i only saw two as the third companion is mag 13.5 way out of the range off my scope. Even splitting AB was hard as it's only 1.5". The mags are 5.8/7.8 and boy was it tough. I spent ages on this one and I managed a peanut split with 6mm Delos and when I inserted the 3.5mm Delos I may have split using x240, but I'm not 100% sure.

I finished about 23.30 and had been out for over 4 hours and I was frozen, even though I was dressed very well with all my thermal gear on. It took me 3 hours to warm up.

[cotterless45]

Can't get better than that ! Triples , colour and the eternal delight of observing binary stars ,

Nick.

[Doc]

Thanks Nick I used your observing guides to pick out some of these stars to observe so thankyou for that.

I really enjoyed the laid back approach of star hopping to your intended target, finding the actual star amoung the all those twinkling gems in your vision and then spending time trying different eyepieces to achieve that split.