Ok, I hope you're not sick of these images yet... here's a closeup of Io from the data recorded on August 18. I had seen something on Io when processing some of the colour images in the other thread, and I wanted to come back and do a run focusing in to see how much I could extract.
Here are four images - red, green, blue and a colour composite which might be approximately how it really appears.
The red image shows the expected polar darkening, except for a hint of a bright spot near the south pole (bottom) that shows up as a notch.
The green image looks about as expected, maybe a slight amount of asymmetry in the darkening between north and south poles.
The blue image is the interesting one, it shows a prominent dark spot in the southern hemisphere. I have no idea what this might be, maybe someone can figure out if this is associated with any known geological feature.
Wow Anthony, initially without looking at the images I was going to jokingly suggest an Ionian volcanic eruption and you've captured the plume. Now after looking at the images I'm not so sure about joking about it. What detail. Fantastic
Wow, wow and wow again! Those views of Io against the disc of Jove are quite 3D and haunting in their detail and clarity. This is really quite astonishing work – congratulations on recording these super hi-res images and thanks for the space mission-like views!
Very similar to the features I got in May 2008 Anthony. It is almost remarkable how this moon has darker poles when in front of the planet.
Just out of interest I attach the image of Io I captured. As you can see the markings are almost the same. I cannot remember if it is tidally locked, with images this far apart it appears to be the case.
Fabulous details there Anthony! I actually believe you might be able to spot a volcanic plume one day, there have been some pretty big ones in the past and with the constant advances in imaging equipment and techniques it is not unlikely. Such a capture would be absolutely sensational.
Since Io is tidally locked, I suppose you could get practically infinite data on it for stacking by adding lots of sessions together?
Thanks guys. The dark spot in the blue channel is the interesting part for me - it probably indicates an area that is reddish in colour, similar in size to the Pele area on Io.
I also checked the JPL simulator, but I'm not sure how accurate the surface detail is, esp, as Io resurfaces itself via eruptions pretty often.
The last photo is fantastic! I never saw such detail on Io from Earth. Congrats and thanks for sharing. I´m showing you the photo to people around me. They say ¨Whats an IO?¨
A most interesting comparison Bird, Io, with a diameter of 3642 km is slightly larger than our Moon and to be able to record albedo shading on it at a distance of approx 778,300,000 km is pretty amazing.
It will be interesting if you manage some more nights of excellent seeing while in Exmouth, to see if you can add to this data from Aug 18th.
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Fantastic 
