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Binary Tour of Lyra

Jamie Dillon


In July, I had fun going through the double stars in Lyra. This article may serve as a reminder of fun and easy sights for crusty veterans, or an interesting diversion for other crusty rookies.

Most famous are of course the big guy, Vega, with its tiny companion, and epsilon Lyrae. It turns out that Vega is an optical double after all, a "so-what" at this point. The double-double is famous and on everyone's hot list for good reasons - orbits within orbits.

Now for the treats that get passed up on the way to the ring. Delta Lyrae is shown on the charts as delta 1,2, but is nowhere listed as a binary, that I can find, from which I presume it's an optical double. But what a star field! In a 1 degree field, the stars around delta Lyr form a captivating pyramid.

Here's an extrememly artful shape that happens to show in a wide-field view from the angle of this planet, like the way a snowflake looks on a cold objective if you get it under the microscope in time. Beauty for its own sake. Now who has the time to set up an asterism just so, to provide a spare lovely sketch like that, just at the right time across the epochs?

Beta Lyr is a pair with close companions, with the primary a tad bluer and much brighter than the secondary, which shows white. Of course the y-pattern around beta is a comforting asterism for navigating. Eta is off to the northwest a bit from Vega, almost an even white pair in my scope.

Zeta Lyrae is the secret gem hereabouts, a lovely blue-white pair. The brighter is a bit bluer. Worth the visit.

I know this is Nortonish and quaint, but as you can see I find binaries captivating, ever since that moment last winter with ole #31 when I aimed at Mintaka. The planetary orbit experts have started to calculate possible orbits for a viable planet in a binary system. Visually the surprise factor doesn't fail to get me. Also, while the big scopes up on Mauna Kea and Paranal and in orbit, as well as photos, just smoke our instruments for deep sky, our scopes are optically optimal for visuals of most multiple systems.


Mail to: Jamie Dillon
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Last updated: July 19, 2007

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