The Other Double-Double of Lyra

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BobSikes
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The Other Double-Double of Lyra

Unread post by BobSikes »

The WhatzUp challenge for August is to find the “double-double”. Not the double-double, but the other double-double in Lyra. Start with our familiar summertime favorite the Summer triangle. This is formed by the bright stars Vega, Deneb and Altair, and finding this huge triangle is as easy as going outside at about 8:30pm, point yourself east and look up. Assuming it’s not cloudy, the only stars you will see in the twilight above will form a nice triangle high in the sky – ta da! The summer triangle, with the brightest star being Vega – the alpha star of Lyra.

After its really dark, find Vega again and look for four stars below it that form a parallelogram (a knocked over rectangle). This is the constellation Lyra, the harp. The four corner stars are designated, in clockwise order – Zeta, Beta, Gamma and Delta Lyra. If you look carefully at the Delta corner star, you can probably see that it’s really two stars- Delta1 and Delta2, and if not, put some binoculars on it and you’ll see it’s a bunch of stars with two main ones. So you’ve found your first double star in Lyra – the deltas. With a small telescope you will also see that Beta and Zeta are nice close double stars, while gamma is an extremely close (e.g. 1 arc-sec) double star that for most scopes looks like a single. BTW, Beta and Gamma also have classical names, Sheliak and Sulafat.

If you know your Greek alphabet, you might be wondering, “what happened to Epsilon”? Look again at Vega and near by you will see a star with similar brightness to the four corner stars. That’s epsilon, and that’s the next double to split … and then split again. First try to see that epsilon is a naked eye double star, but much closer together than delta -- only a bit more than 3 minutes of arc separate eps1 and eps2, an easy split for sharp eyes, impossible for my old eyes. Binoculars will do the job easily. Aim at Vega and notice the obvious double star in the field. That’s Epsilon 1 and 2.

But wait there’s more! Pull out 3” or more telescope and your strongest eyepieces. On a good night, somewhere around 80X and more, both Epsilon stars split again, thus the double-double. The separation of the close stars is between 2 and 3 arc-sec. A good game is to see how low a power you can use to clearly see the separation. And how small a scope. Can the Light Thimble split them?

And now the main challenge, let’s find the “Other Double Double” of Lyra. Web sites can show you the way, but the challenge is to find it yourself, unassisted by star charts, photographs etc. I’ll only say that if you start with Gamma Lyra and search east (left) and up a little from Gamma, you will find it. It lies within your typical finder field, when centered on Gamma. Sweep around for a bit at low power like magic, the double-double! But much easier to split. It’s a nice discovery every time you spot it, and you’ll probably find them to be more colorful than the real double-double. In addition to ease of separation, there’s another big difference between the D-Ds, can you see it?

Enjoy, and please post your observations.
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AstroGeek
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Re: The Other Double-Double of Lyra

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Bob,
I always enjoy your WhatzUp presentations. I'm sure I speak for the club when I applaud your monthly effort in putting these together.
Steve
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NGC7000
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Re: The Other Double-Double of Lyra

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I'll second that, Steve.
Tom H
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Bruce D
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Re: The Other Double-Double of Lyra

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As I always say, the highlight of every meeting!
Bruce D
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BobSikes
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Re: The Other Double-Double of Lyra

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Thanks Guys,

Now get out there and find the other double double. :twisted: I wonder how wide a field you can image it, and still split it. Ideally including Gamma Lyr, but that's about 3 degrees away. Perhaps stitching several shots to show the star hop. Get to work!

FYI - I'm going to put up another challenge soon. I'll give you a heads up with a hint. Check out the link below and I think you'll know what image I'm imagining. And also viewing reports of this amazing phenomena, occuring again on 8/18 at 2:34am and 10:25pm

http://www.celestronimages.com/details. ... ge_id=6995
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Rotorhead
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Re: The Other Double-Double of Lyra

Unread post by Rotorhead »

That's what I like about Whatzup: it's a motivator. Not just with the fava beans and all, but somehow Bob always comes up with a few basic 'gotta sees' and some real challenges. Of course, I'm out of the running on the fava beans for the Other Double Double, since Bob himself lured me to his telescope and showed it to me.... :cry: BTW, it is even nicer than the original DD, since, as Bob mentioned in his presentation, there is lots of color in this one. It's pretty - get out and see it!!!
Bob M
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Re: The Other Double-Double of Lyra

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Dr. Whatzup the picture sure makes it look like there's more contrast 8)
Bruce D
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Mark G
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Re: The Other Double-Double of Lyra

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Bob,

GRS :?:
Clear skies,

Mark

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NGC7000
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Re: The Other Double-Double of Lyra

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C'mon, Mark. Think! Look at the picture....GRS.....Sounds like....uh,...ok..try ....gaywedspa. :lol:


Tom
Tom H
"Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world. Science is the highest personification of the nation because that nation will remain the first which carries the furthest the works of thought and intelligence." - Louis Pasteur
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mrgizmo65
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Re: The Other Double-Double of Lyra

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:shock: :shock: :shock: :shock: Bob, even with me being a "rookie" I enjoy the information each of these chalenges provide and now that my scope is working I make it a point to use that info to do my own viewing. It adds to the experience and helps me to put the little pieces together. Thank you for your efforts. Jerry :mrgreen: :mrgreen: :mrgreen:
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