Jupiter is nearing opposition so I set myself the target of getting a picture of one of Jupiter's moons - but not the usual four. Tonight my target was little Himalia.
Himalia was only discovered in 1904 by Charles Dillon Perrine. Himalia has is tiny in comparison with the four Galilean moons and has a mean diameter of 185 km.
I took two pictures separated by about about 90 minutes and cropped out the region containing the moon. It barely shows up on a two minute exposure taken through an 80mm refractor. Himalia was around magnitude +15.
Himalia orbits Jupiter in an elliptical orbit at an average distance of 11.5 million km. It takes more than 250 days to orbit Jupiter. The next picture shows just how far Himalia is from Jupiter and the Galilean moons - almost two degrees! You could fit four full moons into that gap on the sky!
Here was the view through the 8 inch Meade LX10 showing the four Galilean moons. From left to right: Callisto, Europa, Jupiter, Io and Ganymede.
And finally the closeup of Jupiter with the QHY5 Mono camera at prime focus of the 8 inch, The Great Red Spot was near the meridian (but it's not too clear because of bad seeing) and the shadow of Europa on the cloud tops of Jupiter.
Dr Adrian Jannetta
Guitar strummin' explorer of the universe. Mild mannered maths teacher by day and astronomer by night.