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Patricko
professor emeritus
Reged: 01/30/07
Posts: 714
Loc: around the corner
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Hi everyone, I've looked at this double everytime its out with my 10X50s. Very nice binocular double to observe. Anyone else like to observe it?
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Clear skies,
Patrick
 "Life is too short, go collect some photons!" - Me, myself, and I
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SaberScorpX
Post Laureate
Reged: 01/12/05
Posts: 4120
Loc: illinois, usa
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Sure do.
The easy pair of 6th mag G-type suns (sep 40.0")
also shine just a half degree west of the Blinking Planetary
(ngc6826). A nice counterpart to 61 Cyg decorating the Swan's
eastern wing.
Saber Does The Stars at
www.astronomyblogs.com/member/saberscorpx/
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VanJan
super member
Reged: 07/09/08
Posts: 111
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A very nice cpm pair in my 8x42's as well. Some perspective to ponder the next time you view 16 Cygni. According to the distances for the components listed in MSA, that little gap between the stars you see in your binoculars is at least one light-year across.
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Patricko
professor emeritus
Reged: 01/30/07
Posts: 714
Loc: around the corner
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Wow! One light year! 
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Clear skies,
Patrick
"Life is too short, go collect some photons!" - Me, myself, and I
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tigerroach
sage
Reged: 08/13/08
Posts: 292
Loc: Houston, TX
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I just snagged 16 Cygni for the first time a couple weeks ago in my 10x30s. 
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Brian
TeleVue TV-102, Gibralter alt-az mount
Webster 14.5" f/4.3 truss dob *under construction*
Canon 10x30 IS binocs
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Patricko
professor emeritus
Reged: 01/30/07
Posts: 714
Loc: around the corner
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Excellent!
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Clear skies,
Patrick
"Life is too short, go collect some photons!" - Me, myself, and I
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GlennLeDrew
professor emeritus
Reged: 06/18/08
Posts: 564
Loc: Ottawa, Ontario, Canada
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Where did this figure of 1 light-year come from?... At a distance of 70 l-y and with an angular separation of 40 arcseconds, the projected separation works out to 0.014 l-y, or 860 A-U. Of course, this would be the minimum separation if both stars lay at *exactly* the same distance from us, which of course isn't too likely from a statistical consideration.
If the components of 16 Cyg were actually separated by 1 l-y in the plane of the sky, their angular separation would be 0.82 degrees. And here's the thing. Such stars could indeed be in bound orbits of this size! In such case, their binarity would only be betrayed by their common proper motion (coupled with other indicators such as parallax and spectral classification, to seal the case.)
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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VanJan
super member
Reged: 07/09/08
Posts: 111
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Yes, my "one light-year across" is a simplification of the distances given in MSA of the two components of 70 and 71 light-years as it ignores the "depth" of the view as opposed to a planar projection. Across was a terrible choice of word on my part. Down and through would have been more accurate. Thanks for doing the math behind my poor choice of vocabulary. But, as you note, as a cpm pair, still pretty impressive.
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GlennLeDrew
professor emeritus
Reged: 06/18/08
Posts: 564
Loc: Ottawa, Ontario, Canada
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Those distances of 70 and 71 l-y... the errors on the measurements are large enough that one can't rely on the reported difference of 1 l-y at all.
It's actually much safer to assume that the members of a binary or multiple system which doesn't yet have an orbit solution to lie at *exactly* the same distance from us. Then, considering all possible relative positions on the orbit and the inclination of the orbital plane, it probably turns out that the projected separation would be fairly representative of the actual space separation, from a statistical consideration.
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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