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There's an extra moon around Jupiter tonight

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#1 tomhole



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Posted 26 May 2003 - 09:09 PM

Got all set up with the XT10 and Denks to watch the Io transit and, whoa, there's an extra moon on the left side (right side, in proper orientation). I could see it in the Denks, 25mm plossls, 2.5x powermate which gave me 96x. I could see it without averted vision. So, I plopped the 25 plossl in the 2x barlow to see if it was there in cyclops. Yup, but I needed a little averted vision.

Took a look at Carts du Ciel and it showed a star there. SAO 98271 (not sure what that means, but that's how it was id'd), magnitude 9.33. That was pretty cool.

So, I got all set up to do some comparisons between bino and cyclops mode on Jupiter. I put the binos back in at 96x and, wait a minute, there sure is a lot of light loss in these darn things. Must be dewing up the ep's or something. Took a look at them and they were fine. Looked at Jupiter again and man, it sure is a lot dimmer than the cyclops wiew. Then I looked up at the sky and I couldn't even see Jupiter. A high cloud deck had rolled in and I hadn't noticed. Well, that ended the evening. No Io transit for me and no light loss comparisons either. Seeing was looking pretty good, too. Maybe a 5 of 10. I actually saw somewhat of an airy disc at 429x in cyclops mode.

Anyway, did anyone else see that extra moon?

Clear skies,


BTW, I'm putting this in both bino forums. Not sure if everyone's made the switch yet.

#2 Guest_**DONOTDELETE**_*

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Posted 26 May 2003 - 09:29 PM

Hi Tom:

It's clear here, but the sun is just setting now. I'll check it out later and let you know.

Clear skies,

#3 Guest_**DONOTDELETE**_*

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Posted 27 May 2003 - 12:01 AM

Hi Tom:

Well, I found SAO98271, but it wasn't easy. From out here it's about 6 arc seconds from Europa. And, having a mag 0 object that close to a Mag 9.33 star was not an easy split.

I started by expecting to find it with a pair of 16mm Naglers in the Denk. No go. I hadn't even checked where to look beforehand. Tried 12mm Radians, then 10, then 8. At 8 (about 406X) in the Radians I realized that something was next to Europa. Came in and checked The Sky and that's when I saw the 6 arc second split.

So, I tried several different combos. Once I knew what I was looking for, I could see it in the 10mm Radians, but not the 12s. Got it in 12.5 Ultimas, and 12.5 Orthos. Just a little to the right (left in correct orientation) of Europa.

And, IO is just edging off the disk of Jupiter. The shadow transit should begin soon.

I must admit that without your post, I wouldn't have even noticed it.


Clear skies,

PS - A further check of The Sky shows I accidently looked at just about the closest separation of the night. An hour from now and it will be easy. An hour ago, and it was also easy.

#4 Gary BEAL


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Posted 27 May 2003 - 06:03 PM

Hi Guys,
after reading your posts decided to set up the MN66/ToUcam Pro and shoot it. My imaging at this early stage is more frustration than anything else, but shot Jupiter just as the sun was setting, so about 0515 UTC. Couldn't manage the star, but got the shadow, and the moon. A low resolution copy so it doesn't take too long to load.

Attached Thumbnails

  • 2395-jup 27th mn66 2 4x 04 copy for web.jpg

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