My alarm clock failed to go off this morning and I woke up with just enough pre-dawn darkness to take just six 90 second images of C/2013 US10 Catalina on its outbound journey beyond our solar system four days past it closest approach to Earth. The comet is heading northward above the cup of the Big Dipper and is still bright enough to see through 10×50 binoculars under exquisitely dark and clear sky from 5,000ft above sea level. The waxing moon will allow one more imaging opportunity tonight before it becomes too bright to image this once in a life time visiting comet that grows more distant and dim.
This image covers a 162×246 arc minutes field of view or approximately eight full moon widths. A Borg 77ED f/4.3 scope and a Nikon D7000 set at ISO 6400 were used to capture six 90 second exposures that were stacked. Galaxy NGC 5322 glows at magnitude 10.9 at the lower left corner with NGC 5348 to the upper right of it.
