Cracking open the Doubles

[toml42]

Never thought i'd get into doubles, sad to say, they just never sounded that exciting...

but i literally fell in love upon viewing Albireo for the first time, especially when defocussed slightly, the colours are vivid! so used to seeing the sky in shades of gray, which makes it an even nicer surprise

upon this, i decided to test myself and my setup, so i jumped at the Double double in lyra. Seeing wasn't fantastic, but i thought i'd at least have a go.

Centered them in the eyepiece at 200x at first... nothing. I thought the stars seemed a little elongated, but chalked that up to knowing what i wanted to see! Then, for about 10 seconds, a brief window of perfect seeing, and it was as clear as anything i was looking at 4 stars, not 2! I made a mental note of their positions, and hit up stellarium... sure enough, they were laid out as i had seen them

So, can anyone suggest me any other pretty doubles, or ones of a similar separation to those in the double double?

[abumuhannadh]

Cracking Open? i like that

[yeti monster]

I keep spotting double whilst trawling the fuzzies, I should really take note of where I see them. I'll let you know of any that I come across in future.

[Talitha]

Hi Tom, there's an Albireo look-alike in Lyra which you might like, it's lovely.

Here are some of the designations, Stellarium's bound to include a few of them. I've also attached a screen capture from the Sky Tools 3 program regarding it's location. (The red lines indicate a triangular pattern you can use to locate the double easier.)

HD 175635

SAO 67566

PPM 82026

HIP 92833

STT 525A

[david o]

Hi Tom,

You could try Double Stars for Small Telescopes by Sissy Haas. More doubles than you can shake a pointy stick at. Or The Cambridge Double Star Atlas.

Apart from Albireo and the Double-Double she highlights some other "showcase" doubles for summer/autumn:-

β (beta) and ζ (zeta) Lyrae

β (beta) and δ (delta) Cephei

η (eta) Cassiopeiae

If you don't want either book, or can't wait for them to arrive, try the Saguaro Astronomy Club Double Star Database. You can get v4.0 (zipped) and other good stuff from the SAC Downloads page.

HTH

[Moonshane]

Alberio is a real stunner. There's lots of great doubles and triples about in the sky.

Rather than suggesting specific ones, I'd say use a site eg The Constellations and work your way through the specified doubles for a constellation or two in an evening. There's some nice ones in Cassiopeia, Aquila and Bootes but really they are all over when you start looking. Our own system is actually unusual that it's a single star system. Even Polaris is a pretty double and then there's Mizar / Alcor in Ursa Major; stunning in a wide field.

[DarkerSky]

Albeiro is a stunner. Searching out double stars can be really addictive. I'm always on the look out for double doubles and triple doubles in the same FOV. Can be pretty awesome when you find them

[Mark at Beaufort]

Tom you might find the attached pdf list of doubles useful.

Mark

[toml42]

Thanks for all the wonderful suggestions everyone, some fantastic resources here, these will keep me going for years! ha ha.

While we're at it, does anyone have any particular tips for resolving close binaries for a newbie as myself? I've been lead to believe that an exit pupil of 0.5 - 1mm is optimal for this sort of work, and the 1mm exit pupil i got from 200x in my 200p certainly appeared to hit the spot. Does this correlate with your experiences?

[philj]

Hi toml42, I was like you not really fussed about doubles until recently now I include a few doubles in every nights session. I was looking at Albireo the other night as well, lovely sight another look alike is Epsilon Bootes but you will need a higher mag to split it. The components are closer than Albireo but similar colours.

Philj

[Steve1976]

My own personal favourites other than Albireo right now are Cor Caroli (Canes Venatici), Gamma Delphini (Delphinus) and above all Ras Algethi (Hercules). I managed to track down Struve 2470 and Struve 2474 two nights ago which are also a double-double in Lyra - not as great as Epsilon Lyrae and for me harder to find but still quite nice. I second getting the Cambridge Double Star Atlas, its fab.

[kris h]

Im a big fan of the doubles and variable stars albireo looks amazing

another one i cant wait to see is the Red Giant MIRA and its companion star the skies were clear last night so iwent out with my binos to have a look at Rho cassiopeiae when i read about this star i thought i have to get a look at this. its a Hypergiant star and is about 500 times the size of our sun and 500,000 times more luminous

[toml42]

Just discovered my scope was quite badly collimated, so i'm pretty impressed with my success with the double double! Will have to have a comparison peek now i'm properly collimated, when skies permit...

[barkis]

Double star observing is a superb arm of observational astronomy Tom. There are more double stars than loners in our galaxy, and most are very interesting in one way or another.

Ian, (Lunator) has a wealth of knowledge on the subject, and if you need any help or advice,he will be pleased to help you.

Ron .

[lunator]

Hi Tom

There are hundreds of good doubles to view.

I'll dig out my observing log and post up some good targets

Cheers

Ian

[great_bear]

If you load EQMOD onto your PC, try the "doubles tour"

[toml42]

Thanks guys, this really is a great community, everyones always so eager to help!

Collimation update:

Only had time to view the double double briefly before being engulfed in cloud, but the difference was phenominal! It seemed there were yawning gulfs between the four hard points of light, rather than a brief suggestion of a gap between slightly messy blobs. bearing in mind, i think the seeing was actually slightly worse this time.

ANYONE READING THIS WHO HAS A NEW SCOPE AND HAS NOT YET CHECKED THE COLLIMATION, DO SO NOW!

It took me less than half an hour, with no specialist kit, and the difference is beyond belief!