Monday, September 30, 2013

EV Ceti

I spent Saturday night watching an eclipse.

The faint (11th magnitude) star EV Ceti is in fact two stars, very close together, that orbit each other in less than a day. We can't see this directly - they are far too close. But we can measure the consequences. Mostly, the light we see comes from both stars in the binary pair.  But every ten hours or so one passes in front of the other and the total light drops.

On Saturday I took one 50s image each minute for four hours, and captured and measured the brightness of the star.  And of course duly submitted the observations to the venerable American Association of Variable Star Observers.