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Sketched September 26, 2003 from my back deck in San Rafael, CA at 10:00 p.m. pacific DST (daylight savings time) or 05:00 UT September 27. Seeing deteriorating, fog approaching, transparency poor with fog everywhere.

Date: 09/27/03 Lat 37N, Long 122W, elev. 200 feet Sketch Time (UT): 5:00, (local time): 10:00 p.m.DST
Central Meridian: 125° Filters: none
Instrument: 10-inch (254mm) f/7 home-made Dobsonian reflector. Distance from earth 0.44 AU, 66m km, 41m miles
Magnification: (6mm) 309x  Vixen Lanthanum Transp. 1/6, Seeing 2/10, Antoniadi (I-V):  III-IV
Apparent Size: 21.4" Magnitude: -2.2

Details about Mars: Diameter 21.4 arc seconds (Jupiter is about 30 -50 arc seconds in diameter depending on its distance from earth). Central Meridian 135 - 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.

The terminator, where daylight ends and evening begins on Mars is back! The terminator is on the other side of the disk now that we have passed opposition and Mars' phase is now 95.8%.

Mare Sirenum and Mare Cimmerium are rotating on the disk the eastern or right side of the sketch. Below the south polar cap is a dark feature - Mare Chronium and Aonius Sinus looking something like a horseshoe, with rought Solis Lacus below (north) of this. it was a poo r seeing night. But phase was visible, withthe terminator on the east (right) and the limb haze onthe west (left). A haze over the North Polar area was visible too.

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