TheSkySearchers

I found epsilon Lyrae on 16 November 2020 at 0029 CST (UTC-6).
I found eta Cassiopieae on 18 November 2020 at 2034 CST.

The view of eta Cass 12 arc seconds separation verified the view of epsilon Lyrae because in that view the first double was easy, but the others just looked like stars in the field. But the separation at 208 arc seconds was very much greater (more than 17 times). So, I understood what I had seen two nights before.

The last view of eta Cass was with an 8 mm and 2x Barlow in an f/6.47 ES-102, so 165x and a nice Airy disk.
Normally, I would have just used the best high-power arrangement for this instrument, a 17mm occular with a 2x Barlow. But last night I tried the 8 mm on a suggestion that I read online here:
"Actually, there is no such thing as “empty” or useless magnification. Discard all obsolete rules! In my exerience …" Ronald Stoyan, The Visual Astronomer (http://visualastronomer.com/).
Stoyan says that given time, the eye will adapt and pick out details. I add that it is as much the brain as the eye that sees, but I accept the teaching point.

Thanks Michael !

Yes, doubles are really amazing! One of the reasons that I started observing!

Thanks for the nod, Juno. I looked at eta Cass again and satisfied myself that I saw it correctly the first time: a yellow-white star with a blue-white companion. I looked it up in Burnham's and a lot is uncertain about the pair, especially the companion.

"Some observers have seen the components as gold and purple, some as yellow and red, others as "topaz and garnet."

-- Burnham p 493.

"Actually, there is no such thing as “empty” or useless magnification. Discard all obsolete rules! In my exerience …"

I would agree with this if splitting very close doubles but not for regular high powered viewing.
A blurred image is a blurred image.

Congrats on the first two splits Michael!

Epsilon Lyrae is the famous Double Double. The first split at 209" is easy. However, each of the components splits in two:

AC - 209"
AB - 2.3"
CD - 2.4"

You should be able to split all four with your 102mm at 165x.

I love doubles.
I’m happy you found some!
Are they really your 1st?
I can point you to a list of 200.

Bigzmey wrote: ↑Fri Nov 20, 2020 3:08 am You should be able to split all four with your 102mm at 165x.

I tried last night and I will try again.
Thanks for the encouragement.

Bigzmey wrote: ↑Fri Nov 20, 2020 3:08 am You should be able to split all four with your 102mm at 165x.

Yes. Attached scan from my notebook shows that I viewed them at 1851 hrs CST (UTC-6) on 20 Nov 2020. Thanks, again, Bigzmey, for the nudge. A lot of success comes from accepting the possibility. I could not get them with the smaller scope. I think that the 70 mm just does not gather enough light. Truth be told, mine is held together with rubber bands. So, maybe it can be done with the lesser diameter.

Nice job splitting those. My favorite is Albireo.

mikemarotta wrote: ↑Sat Nov 21, 2020 5:55 am

Bigzmey wrote: ↑Fri Nov 20, 2020 3:08 am You should be able to split all four with your 102mm at 165x.

Yes. Attached scan from my notebook shows that I viewed them at 1851 hrs CST (UTC-6) on 20 Nov 2020. Thanks, again, Bigzmey, for the nudge. A lot of success comes from accepting the possibility.


I could not get them with the smaller scope. I think that the 70 mm just does not gather enough light. Truth be told, mine is held together with rubber bands. So, maybe it can be done with the lesser diameter.

Congrats on this fine split Michael! You have an excellent scope for splitting doubles, with practice you can do even tighter splits.

Yes, doubles are fun and interesting. I have logged about 500 pairs so far this year, maybe a few more. I am going for as many as my 6" refractor will resolve, under about 9 seconds separation.
If anyone wants to compare notes, let me know.

Hi Mike. A wonderful report from you. Even in only fair skies you can still accomplish something with spitting doubles. And, like helicon (Michael), my favorite is Albireo with the pretty blue-yellow pair. Thanks for your great observing report Mike, and keep looking up.

The maximum magnification Stoyan suggests (3XD in mm) is consistent with the maximum Rutten and Venrooy (Telescope Optics,18.10) ) describe on high contrast objects. On planets the maximum of Stoyan is in accordance with the linear resolution power Rutten mentions. (not to be confused with resolving point sources like stars)

Even our ancestors with their long focal achromats spoke of 40X per cm of aperture for special objects like very close double stars ( Norton's 1910) So, you have notorious companions. The 2XD rule is not set in stone, but unfortunately our atmosphere often "thinks" otherwise.

Mars, Saturn and Moon can easily take high magnifications. Jupiter with his low contrast surface details, not. I use 3XD on equal doubles too, close uneven doubles have rules of their own.

The night before last, I went out at 2:00 AM to pursue Sirius. No joy. I went down to 8mm with 2X Barlow and tried a couple of filters. I was impressed with the view of Sirius - almost a steady disk - but I could not spot its companion. My urban skies could be the limiting factor or maybe the aperture of the objective (102mm). I have made the "double double" again, but cannot do that with the 70 mm refractor, even down to 8mm with Barlow.

Viewing at twilight can help with your chances of seeing the pup as the main component is not as bright as when fully dark.
Sometimes a thin haze of high cloud can also help act as a filter.
Keep trying and you will get it with the 70mm

Not to discourage you, but Sirius is extremely hard target. I would suggest to gain more experience splitting less challenging doubles.

Bigzmey wrote: ↑Fri Nov 27, 2020 11:16 pm Not to discourage you, but Sirius is extremely hard target. I would suggest to gain more experience splitting less challenging doubles.

"A man's reach should exceed his grasp, or what's a heaven for?"

I was encouraged to try by another poster here who said that it would not be easy but could be done with my 102 and 6mm. The failure the other night was not the end of the world for me. You never know until you try. Doubles are not a compelling pursuit for me, just something new to try.

Right now, I am working my way through A Student's Guide to the Mathematics of Astronmy by Fleisch and Kregenow. My review of Hirshfield's Activity Manual is on TSS here: https://www.theskysearchers.com/viewtop ... 10&t=13598 In addition to the basic mathematics of astronomy, I read the history, especially how theory developed over time.

It is a cogent criticism going back to Kuhn's Structure of Scientific Revolutions that we tend to learn the physical sciences as a complete given without understanding how we got to where we are. In Hirshfeld's Parallax is the story of how, 200 years after Galileo, William Herschel finally came to the conclusion that physical binary stars do exist. Proximity is not an accident of viewpoint. So, on that basis, I looked at some binaries. I like going out in the backyard to verify that the universe is pretty much as described in the books. And I like following in the footsteps of the explorers to share what could have been their experience.

I would like to try spectroscopy, but I do not own a camera or a Windows computer. So, I am loath to spend $1000 to image half a dozen stars and say, "That's nice."

I have to confess that much of this is visceral and emotional. After an hour or so with the telescope, I can spend another hour on the porch, just looking up at the stars. Bortle 6 or not, it just feels good.

Lady Fraktor wrote: ↑Fri Nov 27, 2020 8:06 pm Viewing at twilight can help with your chances of seeing the pup as the main component is not as bright as when fully dark.
Sometimes a thin haze of high cloud can also help act as a filter.
Keep trying and you will get it with the 70mm

Thanks for suggestion and the encouragement. The 70 mm is an f/10. It stretches farther than the 102 f/6.47; it just does not gather as much light, of course. With Sirius that seems not to be a problem. Maria Mitchell won her gold medal with a 3-inch. It was a Dollard and, I believe, an f/12 or longer. I will continue to try Sirius. l do not have much sky. With neighbors and trees, I never see a sunset or sunrise. We have city parks I can goto, but I am hesitant to be out and about; and any kind of travel by car is a procedure. I might as well pack it all up and go to the club's dark sky sight 100 km from here. But thanks,again.

ďakujem a nech je tvoja obloha čistá.
Miska
BTW, I was surprised at čistá which I knew from Hungarian as "tiszta." It's a loan word, apparently. They no word for it until they met you folk.

I also use a 70mm f/10, it is my first telescope.

Have a look at this topic:
viewtopic.php?f=6&t=5513&p=50132&hilit= ... s+B#p50132
It contains tons of observing suggestions. You will need them all.