In this image, the cardinal points are oriented north to the right, south to the left, east at the top,
and west at the bottom.

 

    Epsilon Lyrae (ε Lyr / ε Lyrae), commonly quoted as "The Double Double," is a quadruple system approximately 162 light-years away in the constellation of Lyra. It can easily be separated into two components when viewed through binoculars, or even with the naked eye under excellent conditions. The northern star is called ε1 and the southern one is called ε2; they both lie around 162 light years from Earth and orbit each other. When viewed at higher magnifications, both stars of the binary can be further split into binaries; that is, the system contains two binary stars orbiting each other. Being able to view the components of each is a common benchmark for the resolving power of telescopes, since the individual doubles are so close together: the stars of ε1 were 2.35 arc-seconds apart in 2006, those of ε2 were separated by about the same amount in that year. Since the first high-precision measurements of their orbit in the 1980s, both binaries have moved only a few degrees in position angle.

    The component stars of ε1 have magnitudes of 4.7 and 6.2 separated by 2.6" and have an orbital period that can only be crudely estimated at 1200 years, which places them at roughly 140 AU apart. The component stars of ε2 have magnitudes 5.1 and 5.5 separated by 2.3", and orbit in perhaps half that period. ε1 and ε2 themselves are no closer than 0.16 light years apart, and would take hundreds of thousands of years to complete an orbit. An observer at either pair would see the other pair shining with the light of a quarter Moon, less than a degree away from each other.  

    A fifth component of this system, orbiting one of the ε2 pair, was detected by speckle interferometry in 1985 and confirmed in two subsequent observations. No orbit can be prepared from such limited data, but its rapid motion suggests a period of a few tens of years. Its maximum observed separation of 0.2 arc-seconds precludes direct visual observation.

http://en.wikipedia.org/wiki/Epsilon_Lyrae

 

ABOUT THE IMAGE:

DATE: All images taken between August 17th and the 21st, 2010.

    The above image is a compilation of several images taken with different equipment.  For the background image of the constellation Lyra, I utilized the Canon 450D (unmodified) on a tripod using a 18-55mm kit lens at F5.6, and an exposure time of ten seconds.  I was rather surprised to see Epsilon Lyrae "split," in this image as I can only visually see one star with my naked eye.

 

    See below for more image information on the inset images.

 

    For this image, to capture a nice split between e1 and e2, I used an Orion 100ED F/9 refractor, and Canon 450D(modified) @ 2x magnification.  This image is comprised of 22 exposures, 100seconds each. 

 

     For this image, to further split e1 and e2 into binaries themselves, I used a 235mm (9.25") Celestron SCT operating at F/20 and a Canon 450D modified.  I had to reduce the exposure to 1/250th of a second to gain any seperation of the binaries.  Out of approximately 100 exposures, I culled all but 12 to render this image.

 

 

 

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