This morning, 7th May local time, I had reasonably good seeing for about an hour – long enough to capture 7 runs of Jupiter with the Galilean Moon Io and its shadow transiting across the Jovian disc.
The red channel was pretty good in almost all images, but unfortunately the blue channel was pretty ordinary, bringing down most of the images from what they could’ve been. Still, I can’t complain as the last few days have seen some better than average conditions, allowing me to finally start getting some runs on the board with this Jupiter season.
The best two images from the session are shown here, as well as a 7-frame animation of the red channel showing Jupiter rotating and Io and its shadow in transit.
Oval BA is definitely fainter than last year, but still has an orange ring with a lighter/white centre. As Anthony Wesley pointed out in his beautiful image, there’s another white storm which appears to have an orange ring around it just to the right of Oval BA, and in-between the two there’s a dark spot. It will be interesting to see what happens to this trio over the next few weeks.
Continue reading to see the animation and the second image, and to read more about the capture and processing of the images and animation.
The animation below consists of 7-frames of the red channel, recorded over a period of 1 hour and 10 minutes. Click the image to download the 1.1mb animated gif.
The animation was constructed first by aligning the frames as layers using Photoshop, and then exporting the layers as TIF files. They were then opened in Jasc Animation Shop 3 where the animation was created.
The second image from the session is below, and was captured about 50 minutes after the one above. Io’s shadow is just on the edge of the disc and Io is about to cross the CM (Central Meridian).
The images were all captured at 30fps, 1/30s exposure using my 12″ Newtonian, 5x powermate and DMK21AU04.
I almost had a ruined morning, as when I started imaging I was losing half of my light somewhere in the imaging train. I thought it was a fogged up secondary mirror, but after using the hairdryer on it, the problem persisted. I found that my 5x powermate had fogged up inside after not drying out properly from the night before (capturing Saturn).
I had to unscrew the entire unit and clean all the lens elements, before finally being able to use 30fps with no light loss. I lost about 20 minutes of imaging time, but it was better than losing the whole morning!
The weather is looking good again for tonight and tomorrow morning, so hopefully I can finally get a decent image of the GRS tomorrow!
Thanks for looking.