On final approach to TOTALITY!

It's December 8th evening, Julian Date (J.D.) 2,455,175 and we are only a few days from predicted time of Second Contact when total eclipse starts.

The words "1st, 2nd, 3rd, 4th contact" refer to moments when objects in eclipsing systems overlap partially and totally.  Consider a small circle crossing in front of a bigger circle: first, just the outsides touch (1st contact); then the small circle just gets fully inside the larger (2nd contact); later, the smaller circle begins to exit from inside the larger circle (3rd contact), and at the end, the circles stop touching at their edges, before separating (4th contact).

Prior to eclipse, Jeff Hopkins used the past eclipse (1982-1984) to predict contact times and determined a time for second contact to be J.D. 2,455,185 = 19 Dec 2009.  This estimate assumed a fairly straight-line decline in light between first and second contact, but as our Citizen Sky light curve reveals, epsilon Aur hasn't been following a linear progression here.  For the first month, light was dropping uniformly, then in mid-Oct things slowed a while, and last week, observers have reported a steeper drop again.  Very recent V magnitudes are 3.55, and if totality again is about V=3.75, the remaining 0.2 mags could disappear within 20 to 40 days - a bit later than predicted.  You the observer will tell the tale by getting out there and providing those estimates.  Very soon, epsilon will look about as faint as zeta Aur!

In related news, we were successful with the second round of interferometric imaging and can see the dark disk advancing across the face of the F star.  The team is racing to submit a report on this, and as soon as possible, we'll share the details with Citizen Sky members.

If you haven't seen the Astronomy Picture of the Day for Dec. 5th - if features epsilon Aurigae rising over Mt. Everest - quite a sight: http://apod.nasa.gov/apod/ap091205.html .