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Sketched July 12, 2003 from my back deck from 3:00 to 5:30 a.m. pacific DST (daylight savings time) or 10:00 - 12:30 UT. Seeing was best at 3:30 a.m. (10:30 UT) when this particular sketch was made. A generally poor, to horrid night because of our summer weather patterns.

Date: 07/12/03 Lat 37.6N, Long 122W, elev. 200 feet Sketch Time (UT): 10:30, (local time): 3:30 a.m. DST
Central Meridian: 188° Filters: none
Instrument: 4-inch (105mm) f/6 Astro-Physics Traveler Apo refractor. Distance from earth 0.53 AU, 79.5m km, 49m miles
Magnification: 376x  (4mm) Zeiss Abbe Ortho, 252x  (6mm) Zeiss Abbe Ortho, 151x  (10mm) Zeiss Abbe Ortho combined with a 2.4x AP Barcon Barlow Transp. 3/6, Seeing 3/10, Antoniadi (I-V):  IV - V
Apparent Size: 18.67" Magnitude: -1.8

South Polar cap (top) is ringed with a dark melt line, the area of Martian earth uncovered as the polar cap receeds. Below the south polar cap (north and to the far right) is Hellas, the great impact basin.

Dark areas: To the left of Hellas is a horseshoe-shaped feature and a white spot. White spot is Eridania, and dark "U" is Mare Tyrrhenum. North (below) is the albedo feature Mare Sirenum (the lump) tapering to Mare Cimmerium. Mare Chronium is the dark feature near the terminator.

Mars, in this sketch is reversed N/S. South is shown at the top of the image. The south polar cap is the prominent feature. Terminator is where daylight ends and evening begins. The terminator is on the left and the planet is rotating left to right. In my sketches the planet rotates martian east (left) to west (right) to match most other images and sketches. Look for features rotating from left to right in the drawings.

Details about Mars: Diameter 18.67 arc seconds (Jupiter is about 30 -50 arc seconds in diameter depending on its distance from earth). Central Meridian 188 - 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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