August 25, 2003, 06:10 UT
Instrument: 10-inch Starfinder

Apparent diameter: 25".1
Phase: 100%
CM: 86°

The eye of Mars is upon us. Solis Lacus is prominent along the central meridian. Popularly referred to as the Eye of Mars, this roundish feature serves as the iris of the martian eye. It is surrounded by Syria, Claritas, Thaumasia and Sinai, all lighter in tone than the dark Solis Lacus. Mare Erythraeum and Aurorae Sinus border to the east. Bosporos Gemmatus bridges the expanse from Mare Erythraeum to Pontica and Aonius Sinus. The subtle finger reaching from Aonius Sinus to the north and east is Araxes. A darker finger extends from Aurorae Sinus toward the central meridian to the west. This finger passes just north of Solis Lacus, incorporating the albedo features Coprates and Tithonius Lacus.

Taken together, this conglomeration of dark and light markings forms the Eye of Mars. They also are associated with one of the most amazing geological formations in the Solar System. Coprates is actually the Solar System's largest known canyon, Valles Marineris. Valles Marineris is more than 2,400 miles long and 6 miles deep. Typically 30 to 60 miles wide, portions of Valles Marineris are as great as 370 miles across. If this canyon had formed on the North American continent of Earth, it would stretch from New York to Los Angeles.

The South Polar Cap continues to diminish in size, but still blazes brightly white. Its dark collar has been exchanged for something less gaudy, a smoky gray ring which edges the frozen carbon dioxide wasteland. The North Polar Hood, a layer of clouds shrouding the polar cap, appears as a subtle brightening along the northern limb. Portions of Niliacus Lacus and Xanthe are visible immediately to the east. The remainder of the disk looks barren. If not for the rich fleshtone hue, it might remind one of the Earth's Moon.

Mars is two days from its closest approach. But the disk will increase in size only marginally, in fact to such a minimal degree that no visual observer will be able to discern the change. This is Mars at his biggest and best, the god of war reigning over the waning summer sky.

August 29, 2003 August 13, 2003

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Revised: August 29, 2003 [WDF]