Monday, 26 January 2015

Jupiter's triple transit

I got up at 3:30 a.m., venturing out into a frosty January night to the society's observatory. After dragging out the Celestron 9 inch Schmidt and iOptron mount, just the one hiccup occurred, caused by the video image capture software. An annoying but fairly quick restart later, all was well and I managed to get a sequence of 1.5 minute videos of Jupiter setting slowly in the West. UK wasn't the best place to image this triple transit due to Jupiter being fairly low, and in fact I haven't got the third shadow due to poor seeing. I later realised I should have got one more frame. You can see an interesting shadow exchange and Io (the moon moving across the disk) covering Callisto's (larger) shadow at the end of the animation, which runs from 0530-0621 UT, with irregular time intervals.

The image above is Jupiter on the 20-inch for comparison, the following Tuesday night. There is a slight aberration in the optical system, but the moons Europa (and its shadow) and Io are very clearly shown.