AOAS to Seek Funding for Bifilar Micrometer

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The VSE "NeedleEye" digital bifilar micrometer. Paul Van Slyke Engineering produces a limited number of high-quality, precision bifilar micrometers for sale to amateur astronomers and private observatories. The digital model shown here retails for $2450, but during the current sale, the price has been reduced to $1950. AOAS hopes to raise the funds needed to buy one of these professional-level instruments in 2006, to begin our own binary star program. |
True binary stars are pairs of stars that share a common center of gravity, and are bound together by gravity throughout time, forever locked in a spiral dance whereby they actually orbit each other. The only accurate way to measure the masses of stars is by carefully measuring the changing positions of the two stars over long periods of time. Binary systems may complete each orbit in as few as 5 to 10 years, or they may take as long as 20 to 50 years to do so. Such measurements are made by using an instrument known as a bifilar micrometer.
A bifilar micrometer is an instrument which has an illuminated reticle etched into a glass as a "crosshair", with a second single-line reticle that can be moved, with exquisite precision, and be placed over the secondary star of a pair allowing for their separation to be recorded with extreme accuracy. The crosshair reticle can be rotated so that one of the illuminated lines might be oriented to celestial north. This thereby allows the angle of a binary pair to be determined as measured in a clockwise direction away from 0 degrees, which begins at true north. Such instruments are not a common item for sale to amateur astronomers, and those with the quality of workmanship desireable for high-quality measurements are not cheap. A very limited number of companies offer such instruments, and among the best in the world today, are those available from Van Slyke Engineering.
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Our program might become involved with one or more Double Star programs associated with professional institutions around the world. As an example of one institution that we might want to contribute observations to, and as a source of objects that need periodic measurements, the US Naval Observatory (USNO) maintains a magnificent Double Star program. We could use lists available from USNO to produce our target lists for the objects we would observe. USNO maintains several lists such as the Washington Double Star catalog with tens-of-thousands of binary stars in its database. Visitors to their website can easily find hundreds to even thousands of doubles for their own use. It's easy to find many pairs that truly need to have new measurements made. Some of these pairs may date back 100 years or more since their last professional measurements. Besides the USNO, there are other sources of target lists for us to choose from as well.
Any facility such as our Coleman Observatory can become a prodigious producer of professional-level binary star observations. We can begin with what we have now and all we need to start proper observations is a VSE "Needle-Eye" bifilar micrometer. The $2000 price tag is very reasonable considering the quality of workmanship and materials they are constructed from. With proper dedication of some of our members, we could be so very proud of what we might do with our own binary star program and make accurate measurements that would be readily accepted by the professional astronomical community.
Let's put our heads together and find some way to raise the funds we need to purchase a VSE bifilar micrometer of our own. I propose that we make this our focused goal for 2006. We'll entertain any and ALL viable ideas for raising the money we'll need for this project, which gives every AOAS member a chance to actively participate in this goal. Are you with me? Let's get started on those fund-raising idea proposals right away.