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Halfway there!

Citizen Sky is now officially permanent part of the AAVSO. In the coming weeks we will be moving additional content to the AAVSO site and freezing this site as an archive of the 1st three years of the project. Please visit the new landing page for future updates.

Posted by Dr.Bob on October 23, 2009 - 1:01pm

Observers are reporting visual magnitude approaching 3.4, which is half-way between the out of eclipse average, close to 3.0, and the anticipated magnitude during totality, 3.8.  Hopkins and Santangelo have begun to converge on JD 2,455,065 (+/- a few days) as the likely time of first contact (start of eclipse).  Today being JD 2,455,127 (23 Oct), that was 62 days ago.   At this rate, we'll bottom out in totality by JD 2,455,189 or slightly sooner - close to winter solstice.  Jeff Hopkins predicts 2,455,183 for visual, and earlier in photometrically bluer wavelengths.

Fortunately, epsilon, Capella and the kids are rising earlier as winter approaches, making the effort to collect data of any kind easier on a person.  Thus, I urge you to make that effort to get outside at least once a week, armed with eyes, camera, telescope or whatever you have, and report those estimates here at Citizen Sky, data link.  We are scheduled to obtain interferometric measurements this season, and a good light curve will help put those observations in context.  A posting about interferometry will be provided soon, but you can refer to the Citizen Sky videos recently posted for previews.  Happy hunting!

Contact TImes Analysis

SInce we are nearly halfway into ingress I have setup initial contact time analysis. The method used can be seen at Note:These contact time are approximate and will be refined as we get to 2nd Contact. They are also dependent on the values taken for the average out-of-eclipse magnitudes and the average Totality magnitudes. For Totality average magnitudes averages from the 1982 -1984 eclipse were used. Composite magnitude plots to date for V, B&U and R&I can be seen at

Jeff Counting Photons Hopkins Phoenix Observatory Phoenix,AZ USA

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