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Saturn Image 2022/04/05(UT)
Clyde Foster
C.Foster
I had some reasonable conditions before mist closed in this morning.
There is an unusual artefact (I assume) in the R on the edge of the rings which I have not tried to remove.
I suspect a bright spot near the CM in the northern EZ, also in the R,
but the artefact has me second guessing, and it would need to be confirmed. Other than that, a nice session.
Cloud prevented any imaging this morning, but it allowed me the opportunity to have a closer look at my Saturn R image of yesterday,
where I mentioned a possible 殿rtefact・on the edge of the ring.
I must express my sincere appreciation to Martin Lewis who expressed interest in the feature,
and who, having looked at it more closely,
postulated that it could be sunlight, shining through the Cassini division, and being cast onto Saturn below the rings.
This was supported by the Winjupos simulation at the time of observation.
The R data, as usual in 途easonable・conditions for me, was the best,
and I was able to derotate 5 images together from a relatively short time period.
Although the proposed sunlight would not rotate with the planet, I believe this was very close to equivalently stacking them,
and it was at this stage that the feature became quite noticeable.
I took a little bit of time to explore how this would manifest over the last,
and the next few months, and found that the sunlight only first appeared below the ring about 7 days ago,
as shown by the Winjupos simulation of 29 March.
The sliver of sunlight on the edge of the rings should expand, reaching its most prominent about the middle of May.
After that, it slips back towards the rings, and disappears behind the rings on or about the 5 July.
So it certainly appears that this feature may be noticeable, and observable, over the next few months.
As a side note, this is just another reminder that it is inadvisable to 鍍ouch up・or 兎dit out・
what at first appearance looks like an irritating artefact!
[Clyde Foster:Centurion,South Africa]
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