Slightly off topic (not Ganymede) but this post got me scanning through Sky Safari and it seems Io and Europa are working together on their shadow transits, a few of which are in observable hours, although it looks like it might be hard spot Europa's shadow. First one I could find was 3am on May 23rd, then 5am May 30th, 7pm June 2nd, 9pm June 9th...
I'm an infrequent watcher of these things so maybe this is all too common, but it's interesting to see how all these moon shadow transits time with each other. Thanks for the post
