We're in for a couple weeks of clouds and rain. Last night was a rare gap in the clouds so I was excited to have the opportunity for a double shadow transit on Jupiter, even if it was to last only 20 minutes. When I started viewing through the 6-inch refractor at 9:30pm Europa's shadow was just past midpoint and the moon itself was quite far away from the planet. Io was approaching the limb and I watched the ingress. Fortunately Io entered near the middle of the equatorial region, which was relatively dark with orange and umber sunset clouds, so I was able to see the bright yellow spot well into the disk. After a half an hour or so Io moved in front of a narrow light tan seam in the region and I could not recover it. (BTW I have noticed a virtual lack of purple festoons this year, I miss those).
Some low clouds passed from time to time, and I thought it would get completely socked in, but sure enough it would clear and I could still watch the progress. Of course transparency was crummy, and seeing generally poor especially when passing over a neighbor's roof vent, but there were moments of very good seeing to enjoy seeing Europa's shadow get closer to the limb.
After 11:15pm I started watching carefully for Io's shadow, and finally saw a tiny nibble in the equatorial limb. Once it was fully on the disk, Europa's shadow was about the same distance from the opposite limb, and it was interesting to see the balance. Soon enough Europa's shadow slipped from view just as more very substantial clouds came over, so it was time to cover the scope with a tarp and head inside.
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