1:12am Well, it’s 1:12am and there are no moons. I gotta say, it looks pretty strange.
I can clearly see both Europa’s shadow and Ganymede in front of Jupiter through my small but mightly 80mm scope, and a wealth of other detail on Jupiter. Still, pretty strange
1:25am I can’t see Europa itself, which is also crossing in front of Jupiter. I can only see Europa’s shadow, and Ganymede of course. Ganymede is so much bigger than Europa, so the limit of my telescope is somewhere between Ganymede and Europa. Europa also has a higher surface brightness, so it may be harder to pick out against the bright cloudtops of Jupiter.
2:05am I’m taking some photos through the eyepiece (afocal) just to show that there are no moons. I don’t really know how much good a photo is of something that isn’t there…
2:20am Wow! The photo actually shows the major bands and two little marks that are Ganymede and Europa’s shadow. I’m not saying it’s a great shot, but it’s something.
2:35am Yeah, it’s over. Io has popped out of the shadow and Jupiter again has a moon. I tried another photo and it barely shows Io. I suppose it is still partly shaded, and it is so much smaller than Ganymede. I just thought that since Ganymede showed up so well…
2:49am Exactly on schedule! Europa is coming off the limb of Jupiter. It is like a little pimple on the edge of the planet. Also, Ganymede’s shadow is now visible on the other side of Jupiter from Ganymede itself, and it looks huge in comparison to Europa’s shadow. It also appeared right on schedule. You could set your watch by this stuff (and people used to!) Don’t you just love Newtonian physics?!
3:02am Show’s over for this year. Well, for the next 10 years. Next time this happens it will be 2019. Right now, it’s time for bed.
