This morning I was able to push my 10" F5.5 Dobsonian near 1000x utilizing a 7mm Ortho combined with a 5x Powermate. Surprisingly, I could still define features on Jupiter beyond the main equatorial belts and polar regions, including two festoons and Callisto--which I mistook for a shadow (!)--near the southern limb. Even Saturn's Cassini Division was apparent, however not as crisp as I would prefer, but nevertheless isolated and visible around the entire ring's circumference. At 225x, I suspected a small shadow emerging from the SSE corner of Jupiter's disc. Not as sharp as other shadows I've recalled observing, this one was gray in tint and appeared diffuse around the edges. I flipped through Sky & Tel and confirmed my suspicion of this being not a shadow, but the moon Callisto itself. In the past, I've noted Callisto as having a darker (grayer) albedo in comparison to the other moons. To see Callisto this dark against the Jupiter was a pleasant surprise and I do not believe a transit occurred last apparition. I know Callisto was not eclipsed in 2000 according to ALPO. Also at high magnification, I don't recall seeing as much albedo structure on Ganymede prior to this morning. Last apparition I had sketched numerous times the detail in the moon's surface, unfortunately, my window of stability today lasted only a few minutes and I ended up sketching Ganymede from memory. I'm going to try to obtain a bitmap of Ganymede for this morning's position through Guide 7 for comparison. I should also point out another feature on Jupiter I don't recall seeing before, but is striking enough to comment. Between the south equatorial belt and the south polar region, the white zone between the two had a dark band terminating near the CM at ~11:22UT, giving the appearance of an unfinished drawn line. I don't believe it's anything special, though. -Frank Kraljic --- This message is from the AZ-Observing mailing list. If you wish to be removed from this list, send E-mail to: AZ-Observing-request@xxxxxxxxxxxxx, with the subject: unsubscribe. The list's archive is at: //www.freelists.org/archives/az-observing This is a discussion list. Please send personal inquiries directly to the message author. In other words, do not use "reply" for personal messages. Thanks.