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One Planet, Evening of 7/2/14...

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#1 E_Look

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Posted 03 July 2014 - 01:50 AM

... but six moons!

I'm a little bit elated that I got to see not only the usual quartet of Titan, Rhea, Dione, and Tethys, and not only Enceladus, but Mimas as well!

In fact, it was a bit strange, as Tethys, normally greatly more visible than Enceladus and Mimas, was the hardest to see, even by averted viewing. Tethys took all night and 460x-575x to get it, and even then, just one or two fleeting glimpses because by the time I got the bright idea to further up my magnification, Saturn was sinking toward the lower, hazier portion of the sky. Toward the end of my short night, just before 1 AM, Tethys became impossible to spot. It just seemingly went away.

Next hardest was Enceladus. It would fleetingly and tantalizingly appear to an accidental quick glance and the faintest and closest to Saturn of a crooked string of three, from farthest out inward: Rhea, Dione, Enceladus; it materialized again, momentarily, accidentally, avertedly, and then disappear. This happened three or four times. About the time Tethys was no longer visible, it wouldn't come back to view, either.

Mimas, incredibly, stayed in sight, at a few moments by direct sight at almost all powers starting from 400x, and via averted sight from 200x.

What made it all so incredible, including the sighting of Enceladus, was that the transparency was so-so at the start of my Saturn viewing portion of the night and fairly quickly got progressively worse, as I viewed. In addition, the seeing was just a shade better than awful; Mars shimmered and I was able to make out the green areas only because that night the wider greenish features rotated over.

I guess bad seeing might limit the ability to see surface features of a planet, and I barely could make out the band on Saturn, and the Cassini division would constantly disappear and reappear, and was not really ever in good focus. But bad seeing doesn't seem to in itself completely hide the presence of a moon, so long as its position with respect to the Sun and the glare of Saturn doesn't wash it away.

Too bad Iapetus was too far away. Catching it along with these six at one sitting would be something! The last time I was able to see Enceladus, the rings were tilted more closed and that night was very clear with fair seeing. I never thought I could see it this night, but I kept trying and finally when I got to 460x and 575x, I got it... and Mimas was visible all the time, just about, and I've NEVER seen it before!

#2 E_Look

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Posted 06 July 2014 - 11:49 PM

Tonight, seeing was awful and transparency degraded quickly. Mars was essentially unobservable, though strangely, Saturn was much more viewable. I was able to focus somewhat Saturn up to 460x; by that I mean that while the upper atmosphere was quite turbulent, the fleeting moments that things got sharp provided a view of the Cassini division (and really, that only!). But I could initially see Titan, Rhea (natch!), while Tethys, Dione, and Enceladus were momentarily visible with averted vision. Even Mimas blinked in once, though very, very faintly. Very quickly thereafter, the latter three blinked in less and less frequently until only Dione could be seen even by averted vision. I packed it in, I guess after not even two hours. At least I got to see the Saturnian moons.

Oh yeah, the Moon looked great even if it was obvious that the air was very unsteady.

#3 azure1961p

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Posted 08 July 2014 - 03:29 PM

Ed,

Mimas is quite the catch!! I bottom out around 13.5-14.1 under the best circumstances, ie; no bright planet glare nearby, so I write this one off at least from my usual observing locale. I enjoyed your systematic report from moon to moon and the descriptive experience of seeing them. The seeing as of late is worse than usual for this time of year and I attribute it to Hurricane Arthur creating a cauldron of thermal confusion having blown through our midst, if even distantly.

Lousy weather tonight and tomorrow for us but I'm
Holding out hope for better seeing to return that's common for this season!

Pete






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