Tough binary in Lyra

[John]

I've been observing the binary stars in Lyra this evening with my Tak FC100-DL. Rather an impromptu session because the forecast was not for clear skies.

Lots to choose from in this small but lovely constellation.

A first for me, as far as I recall, is Beta 648 which is close to Gamma Lyrae. I got a definite split of this close uneven brightness pair at 281x and 300x. The 8th magnitude secondary lies at a position angle of 251 degrees from the magnitude 5.3 primary and the separation is currently 1.2 arc seconds according to the Cambridge Double Star Atlas. I confirmed these details after getting the split and the PA seems to match where I could see the dim secondary star, just ahead and a wee bit south of the primary as the pair drifted from east to west across the field of view. The primary appeared to be pale yellow and the secondary star greyish.

A nice one to get in 100mm of aperture and I can't recall getting it before

[Sunshine]

I haven’t tackled that binary but, now that you mention it, I’ll have to give it a go.

[Stardaze]

I'll try to remember to have a look at this one too John. I was hoping I might have got a copy of the Cambridge double star atlas for fathers day, but wasn't to be. Another treat for myself soon! 

[Geoff Barnes]

Aha! Now this one should be within my grasp.

Lyra is upside down here with Vega at the bottom and Gamma Lyrae at the top, so the seeing should be better than it is for the Double Double which hugs my horizon.

Thanks @John👍

[wookie1965]

I will have to try that in my Tal then the Meade see how they compare.

Thanks John.

[chiltonstar]

One to try this evening with my 180 Mak and 102mm Vixen achro.

Chris

[chiltonstar]

Quite a nice one. With the 180 Mak last night, the pair were clearly separated with dark space between them, with the secondary appearing as a bright point in about the right place. The colours looked to me whitish yellow. I struggled to separate them with my 102mm f13 achro though - definitely a double, but with the two disks touching.

Always fun to look at these close, uneven doubles - Sissy H is gathering data on 6 Ser at the moment, which is worth a look.

Chris

[RobertI]

Good catch John, wish I’d read this before, I would have had a stab last night when I was out. 

[John]

2 hours ago, chiltonstar said:

Quite a nice one. With the 180 Mak last night, the pair were clearly separated with dark space between them, with the secondary appearing as a bright point in about the right place. The colours looked to me whitish yellow. I struggled to separate them with my 102mm f13 achro though - definitely a double, but with the two disks touching.

Always fun to look at these close, uneven doubles - Sissy H is gathering data on 6 Ser at the moment, which is worth a look.

Chris

I had a nice view of this one with the ED120 last night as well

Also  a first view of Pi Aquilae this year as it cleared the tree line. A tight but even brightness pair. Currently 1.4 arc seconds separation I think ?

 

[markse68]

Had a look last night and it’s surprisingly tight but nice split comfortably with my 5mm @ 320x. Thanks for the suggestion John. This is fun!  Will check out 6 Ser tonight and nearby M5 which I don’t think I’ve looked at before 👍 Antares felt so close to splitting last night but still no go for me here...

[John]

I might set the 130mm triplet up tonight for this and some other challenges

[chiltonstar]

15 hours ago, John said:

I might set the 130mm triplet up tonight for this and some other challenges

How did the 130mm perform John?

I had another look last night (180 Mak) while I was waiting for Jupiter and Saturn* to rise enough and it is indeed a nice pair, although it needs the right mag with a Mak - x300 seems to give the best view I would say to sort the secondary out from the diff pattern.

Pi Aquilae is indeed a superb double - I used the pair a couple of years ago to test the collimation of my 102mm frac after I disassembled the air spaced doublet and cleaned off deposits various before reassembly. When correct, the view was stunning, although it is obviously more impressive with the 180 Mak because there is more dark space between the two nearly matching stars, and the Airy disks are smaller. The pair really do look like car headlamps from a distance.

Chris

* First decent evening (24:00) view I've had this year, with some good belt detail on Jupiter with the ADC in place, and Cassini just beginning to show on Saturn, despite the very low altitude.

[John]

The 130 made the split of Beta 648 that much easier although I didn't think the seeing last night was quite as good. I used 300x - 375x but the secondary was visible from 200x upwards.

I got suggestions of a split on Antares but that one is so low down that it throws up a whole lot of it's own seeing issues !

I didn't stay out too late last night so no planets.

Best of the session was Lambda Cygni which I think is a touch under an arc second currently. Last night at 375x it was a tiny "snowman" with a thin belt of blackness around his "waist" that flickered in and out of view as the seeing varied.

Pairs such as Delta Cygni are a piece of cake with this scope

 

 

 

 

 

[markse68]

6 Ser is a nice double- found it quite easily after finding M5 which is a lovely glob! With M5 in lower left of 20mm ep and 5 Ser top right moving scope up and tight along the line between the 2 about double the distance and there it was. With a 5mm it wasn’t terribly tight but the secondary is tiny and faint and easy to miss. Quite satisfying 😉

ooh Lambda Cyg is tight isn’t it! 

Edited June 24, 2020 by markse68

[John]

52 minutes ago, markse68 said:

..ooh Lambda Cyg is tight isn’t it! 

Probably the tightest that I've split with any confidence, so far

Once you get to an arc second or so the atmospheric conditions become hugely influential I think.

 

 

[RobertI]

On 21/06/2020 at 23:46, John said:

A first for me, as far as I recall, is Beta 648 which is close to Gamma Lyrae. I got a definite split of this close uneven brightness pair at 281x and 300x.

Inspired by your success I had a go at this one with the 150PL tonight. Sadly conditions were just not right, with the star jumping all over the place and no sign of a secondary. I was also limited to 240x - I need more magnification for these tight doubles. So I ended up looking at some nebulae instead. One for another time.

[John]

29 minutes ago, RobertI said:

Inspired by your success I had a go at this one with the 150PL tonight. Sadly conditions were just not right, with the star jumping all over the place and no sign of a secondary. I was also limited to 240x - I need more magnification for these tight doubles. So I ended up looking at some nebulae instead. One for another time.

I found the seeing "variable and hazy" tonight. I gave up trying anything too hard !

Another night and you will get it, I'm sure.

Good move for being flexible and finding something that could be viewed reasonably well