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Io Shadown imbedded in GRS.

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#1 Eddgie


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Posted 15 November 2012 - 12:24 AM

Happening now...11:20 CST!

Io shadow in GRS.

Very very cool. Have never seen this before. I observed the shadow as it ingressed at the limb.. A tiny little bite out of the edge.

Was tranfixed, and did not notice the oval that proceeds GRS had already come into view. Once I realized that GRS was on the limb, I looked closely and cold see that Shadow was imbedded almost exactly in the center of GRS.

As GRS is coming off of the limb, shadow appears to be driftiing north and is not near the edge.

Fascinating to watch. Really superb. Lots of detail on Jupiter tonight.

245x, binoviewers in C14.

#2 Eddgie


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Posted 15 November 2012 - 12:55 AM

2350 CST.

The shadow of Io is now proceeding the GRS with the trailing edge of the shadow just touching the eastern edge of GRS and just inside of the bottom of the belt.

The perfect little pale yellow pearl of Io's disk is now bracketing the GRS on the trailing edge, hovering over the eddys that follow GRS.

Now observing at about 165x. Two very pronounced festoons in northern temperate region.

My first real look at the jr. spot. Very pale and not all that round appearing, but could be positional.

Lots of mottling in the northern hemispheric pole area (sorry my terminology is not great).

Io's little pale yellow disk is a delight to see following GRS so closely. It almost seems to be standing out from the background, like the head of a rivet sticking up. I know it is only an illusion, but it is a very distinct one.

What a treat. One of the most unusual transits I have ever seen.

And I did not know it was going to happen.. Just luck.

But when I was getting ready to post this, I just noticed that someone else mentioned it was going to occur.

I am silly with delight. What fun.
Really spendid.

#3 Eddgie


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Posted 15 November 2012 - 01:30 AM

Last report. Went back out after my last post and was having trouble getting a crisp image of Io. Was there, but not crisp. Seeing was about the same, so I thought it was positional or something. Some of the faintest details were starting to elude me.

50% Dew coverage. Had my dew strip on, but not turned up to 100%, and from past experience, I know that time will clear it, but from 50%, it can take 40 minutes to an hour, so that called my evening.

Still a lot of detail. Io's disk was there, but looked more like a pale oval than a sharply defined disk.

The festoons were showing better I would guess because of positional (one was at the meridian). Pale blue is the way I see them at the root, but CCD images don't show them that color. Tend to show them as gray with a bluish hue.

Was such a cool site though to see the shadow and the moon sheperding the GRS out from the limb. I don't know if this is something that happens with any regularity, but I have never seen it and never even considered that it was a possibility (though now it seems obvious that it could occur from time to time). I feel very fortunate to have witnessed it. And OMG was Jupiter beautiful tonight! Not the best seeing, but not bad, and with only a little patience I was getting lots of good hole action. Very nice indeed.

#4 starrancher



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Posted 15 November 2012 - 01:31 AM

Clouds crept in on me . I'm getting sucker hole views that last a few seconds at a time . Not enough time to even make sure I have best focus .
Crud .

#5 dpwoos


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Posted 15 November 2012 - 01:51 AM

I just got in, after having observed the IO shadow+transit in the GRS. Very cool event, and great seeing here in Vermont - 250x in a 12.5" f/4.7 reflector. Earlier, I had a fantastic view of M31 including very prominent dust lanes and very bright NGC 206. F (and of course E) in the Trapezium was obvious. The only target that eluded me was the Horsehead - some kind of haze had moved in by then. In any case, a great evening and a great start to the Jupiter observing season!

#6 Erik Bakker  Happy Birthday!

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Posted 15 November 2012 - 02:53 AM

Great observing report Eddgie!

Glad you had these splendid views. When I called it a night, the GRS and Io had not yet turned their face to the earth :bawling:

#7 Asbytec


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Posted 15 November 2012 - 05:02 AM

Wish I could have enjoyed such a nice transit, Eddgie. Man, 12 hours difference here. Thanks for sharing, gotta keep an eye out for the next one.

#8 MikeBOKC



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Posted 15 November 2012 - 08:21 AM

If anyone imaged this sequence I hope the post some pics here.

#9 Ashfall


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Posted 15 November 2012 - 10:06 AM

This was an amazing transit, and the best skies yet here since the summer humidity ended. I was able to push to 311x on my C11, unlike last week's transit. The Great Red Eyeball was pretty cool!

I attempted some photos with a DSLR and nosepiece, but could not resolve the shadow in the results. Only my 3rd attempt at astrophotography and with all the wrong equipment.

I found this very nice animation of the November 8th transit. Maybe someone will have one like this from last night.


#10 rtomw77



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Posted 15 November 2012 - 10:08 AM

I was lucky enough to catch a view of this happening last September. It's quite a sight.


#11 Eddgie


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Posted 15 November 2012 - 10:22 AM

One of our wonderful imageing members caught at least one image.

Io and Shadow shepard the GRS

I was seeing it just as the front half of the GRS was rotating into view. At that time, the shadow was only a cresent bite and I did not realize that the GRS was there until I saw the Jr oval and then looked for it.

As soon as the shadow had completly ingressed at the limb, I could easily see that 2/3rds of the GRS was in view and the shadow was just about perfectly centered in the GRS.

Just after the trailing edge of the GRS roated past the limb, I could see that the shadow was already moving towards the leading edge of the GRS and Io was just starting to ingress. I watched as it moved across the limb and it was brilliant. The binoviewers perhaps poviding an illusion perhaps, but Io was centered directly over the limb and seemed to hover quite far in front of the planet. Again, I know an illusion, but a very powerful one.

I easily followed Io in as it moved over the eddy structure following GRS.

Once the GRS was about one lenght inside the limb, the shadow was just in front and Io just behind.

The link of couse shows the picture, but Io looked crisper to me at 165x than in the attached link, and while perhaps a bit more pale, it also seemed to have a pearlescent character. Maybe atmospheric reflections? Don't know, but it was quite beautiful.

Really excellent. Was just getting high enough to be in better seeing and the dew hit me.

But I enjoyed this so very much....

#12 Asbytec


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Posted 15 November 2012 - 10:30 AM

Edggie, I swear as I write this I am watching Europa's shadow embedded in oval BA! Just trailing the center of it. Check it out, 15 Nov 1530 UT and Europa is nearly on the trailing limb as the GRS comes round.

No sooner did I wish above to see the same, and here it is. It's night in Asia as I write this and noon US Eastern time. Maybe someone will image it, too...I hope, I hope. Maybe winjupos can show it?

Later...scope is outside.

#13 Astrodj


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Posted 15 November 2012 - 11:41 AM

Great report Eddgie. I had a similar experience with Io being very sharp at ingress, then later appearing soft. I too wondered if the background change was the reason.

The image link shows what I saw visually pretty well. Moments of good clarity were even better, if fleeting. The illusion of 3D is there for mono-viewers like myself too. Amazing.

And LOL, my terminology is sorely lacking for Jupiter. It usually gets corrected pretty quickly on this forum though!

I did not pick up any of the white spots south of the GRS that the image shows. I wasn't exactly looking for them, but I didn't notice them without meaning to either.

#14 Astrodj


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Posted 15 November 2012 - 11:53 AM

Does the dark spot close to the Oval BA, between it and the GRS, have a name? I was able to see it last night. I've seen it in some of the awesome sketches and images posted on CN, but last night was the first time visually for me.


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