Disappearing Moons of Jupiter

October 03, 2009


Photographer: John Chumack
Summary Author: John Chumack

The photo above shows Jupiter and three of its moons as photographed in early September 2009 from Dayton, Ohio.  A little after this photo was taken all four of Jupiter’s largest moons were lined up either in front of or behind it; therefore invisible to us. Click here to see a clip of the moons Ganymede, Europa and Io in orbit around Jupiter. This vanishing act happens perhaps every five years or so; though it won’t happen again until 2019. On the video, 31,288 frames were stacked in Registax for 10 sets of red, green and blue images; each captured about 10 to 15 minutes apart. I started my viewing session around 11:30 p.m. (local Eastern Daylight Savings Time) on September 3 when Jupiter emerged from behind my neighbor’s tree; Callisto had already moved behind Jupiter. I was able to capture images for several hours until another neighbor’s tree got in the way – astronomy is fraught with frustrations.   

Legend: WI = Wesley Impact Scar; I = Io; G = Ganymede; E = Europa; GRS = Great Red Spot; N = North

Photo details: Firewire video camera; 2x Barlow lens; red, green and blue filters;10" SCT telescope.