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Old 05-06-2017, 04:23 PM
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bigjoe (Joe)
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Join Date: Nov 2010
Location: sydney
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re Ganymede

Originally Posted by pgc hunter View Post
With a massive strong high directly over SE Aus and a very cold frosty night, I headed out as I thought seeing might be on the good side. What I got was conditions at times where stars at 600x showed near-perfect airy disk and diffraction pattern that barely wobbled. The Galilean moons all appeared as satisfying disks at high power, without much in the way of "seeing hairs" that flare around the moons in unsteady conditions. However, Ganymede at high power appeared somewhat "gibbous", so I spent a good hour examining it at up to 600x. I could see what appeared to be a dusky feature just north of the equator, while the northern limb and the south-preceding region of the disk seemed to be higher albedo, certainly moreso than the following limb.
Great've got an exceptional scope or eyes or both..I now am inspired to try in my 10" SCT!

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