Ptolemaeus and Surroundings

Sketch of Ptolemaeus and Surroundings

Sketch of Ptolemaeus and Surroundings
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Observation Notes:

Despite the bad seeing, Ptolemaeus and friends were large and stark enough to put on a good show at 120X. An interesting pillar of shadow within Ptolemaeus seemed bulbous at its tip. It seems likely that this little feature is caused by crater Ammonius. Spörer was a fairly rugged crater compared to deep Herschel. Lunar curvature was beautifully obvious across Ptolemaeus’ expansive floor.

Subject Ptolemaeus and Surroundings
Classification Craters
Position 9.2°S, 1.8°W
Phase/Age 8.1 Days / 57% Illuminated
Size* Ptolemaeus: 153 km dia x 2400 m depth
Ammonius: 9 km dia x 1850 m depth
Alphonsus B
Herschel: 41 km dia x 3770 m depth
Spörer: 28 km dia x 310 m depth
Gylden: 47 km dia
Date/Time AUG 27, 2009, 10:00 PM MST (AUG 28, 2009, 05:00 UT)
Observing Loc. Flagstaff, AZ – Home
Instrument Orion SkyQuest XT8 (203 mm dia./1200 mm F/L)
Eyepieces/Mag. Pentax XW10 (120X)
Conditions Mostly clear, calm
Seeing Ant. IV
Sources Atlas of the Moon by Antoní­n Rükl 2004

* Based on published data.