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Sketched July 18, 2003 from my back deck 4:00 a.m. pacific DST (daylight savings time) or 11:00 UT. Outstanding observing night.

Date: 07/18/03 Lat 37.6N, Long 122W, elev. 200 feet Sketch Time (UT): 11:00, (local time): 4:00 a.m. DST
Central Meridian: 139° Filters: none
Instrument: 4-inch (105mm) f/6 Astro-Physics Traveler Apo refractor. Distance from earth 0.47 AU, 70m km, 44m miles
Magnification: 376x  (4mm Zeiss Abbe Ortho combined with a 2.4x AP Barcon Barlow Transp. 3/6, Seeing 9/10, Antoniadi (I-V):  I - II
Apparent Size: 19.8" Magnitude: -1.9

South Polar cap (top) shows more bald bald spot where the carbon dixoide ice is melting. The dark melt line is more prominent too. Below and to the right of the south polar cap is a white spot, Eridania. Further North and to the left (below) is the albedo (dark) feature Mare Sirenum (the lump) tapering to Mare Cimmerium. The ""C" shaped feature has past central meridian since the previous sketch. Different Mars maps show this as Mare Chromium or Phaethontis. On the terminator is Bosporus Gemmatus (or Mare Erythraeum). Below this is Solis Lacus (dark) and Syria is the light area. The Tharsis volcanoes and Olympus Mons again can be seen as subtle lighter areas right of the north limb. Arcadia, not the North Polar cap, can be glimpsed right below the caldera of Olympus Mons.

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 19.8 arc seconds (Jupiter is about 30 -50 arc seconds in diameter depending on its distance from earth). Central Meridian 139 - 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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