Sketched September 27, 2003 from Mount Tamalpais State Park during the San Francisco Amateur Astronomers monthly public star party, the last one of 2003, 10:15 p.m. pacific DST (daylight savings time) or 05:15 UT September 28. 115 people took a look at Mars tonight through our telescope, one of 30 telescopes set up for this public star party. I stood in line, and took my turn at the eyepiece at 10:15 p.m. for this sketch.

Date: 09/28/03 Lat 37N, Long 122W, elev. 1970 feet	Sketch Time (UT): 5:15, (local time): 10:15 p.m. DST
Central Meridian: 129°	Filters: none
Instrument: 7.1-inch (180mm) f/9 Astro-Physics Starfire Apo refractor.	Distance from earth 0.44 AU, 66m km, 41m miles
Magnification: (16mm) 300x  Zeiss Abbe Ortho with Zeiss Binoviewer and barcon barlow.	Transp. 5/6, Seeing 7/10, Antoniadi (I-V):  II
Apparent Size: 21.2"	Magnitude: -2.2

Solis Lacus, the round 'eye of Mars" is the prominent feature on Mars in this sketch. Left of Solis Lacus, connecting it to Mare Erythraeum is Nectar. North and south of Solis Lacus are Aonius Sinus to the south and Aurorea Sinus to the north. Mare Chromium (or Phaethontis) is the dark feature below the south polar cap, which had some interesting dark markings visible to me. The south polar cap looks a bit larger than a week ago, when it was barely visible. Possibly just the uneven shape is showing more at this CM, tho'

Mare Cimmerium is rotating on the right, next to Mare Sirenum. No sign of either Tharsis volcanoes or Olympus Mons. Pretty washed out northern hemisphere. North (below) Solis Lacus a chain of spots. The first westernmost or right spot is Syria. The second spot to the left is part of Tithonius Lacus, a good visual representation of where part of Vallis Marineris lies. Beteween Tithonius Lacus and Solis Lacus is a lighter feature called Sinai. On the western left edge, a light spot is Ganges/Chryse rotating off.

The North polar area was very interesting. North polar hood was very bright. Arcadia visible too - looks like a white spot where the north polar cap would be. Some dark markings next to Arcadia are possibly Propontis Complex. Terminator and limb haze visible.

Details about Mars: Diameter 21.2 arc seconds (Jupiter is about 30 -50 arc seconds in diameter depending on its distance from earth). Central Meridian 129 - the imaginary line passing through the planetary poles of rotation and bisecting the planetary disk, and is used to determine the longitude during an observing session.

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