Argyre Planitia

Argyre Planitia
Colorized topographic map of Argyre basin and its surroundings, from the MOLA instrument of Mars Global Surveyor.
LocationArgyre quadrangle, Mars
Coordinates49°42′S 316°00′E / 49.7°S 316.0°E / -49.7; 316.0
Diameter1,700 km (1,100 mi)
Depth5.2 km (17,000 ft)
EponymLegendary island Argyre

Argyre Planitia /ˈɑːrər/ is a plain located within the impact basin Argyre in the southern highlands of Mars. Its name comes from a map produced by Giovanni Schiaparelli in 1877; it refers to Argyre, a mythical island of silver in Greek mythology.

Argyre is centered at 49°42′S 316°00′E / 49.7°S 316.0°E / -49.7; 316.0 and lies between 35° and 61° S and 27° and 62° W in the Argyre quadrangle. The basin is approximately 1,700 km (1,100 mi) wide and drops 5.2 km (17,000 ft) below the surrounding plains; it is the second-deepest impact basin on Mars after Hellas. The crater Galle, located on the east rim of Argyre at 51°S 31°W / 51°S 31°W / -51; -31, strongly resembles a smiley face.

The basin was formed by a giant impact event by an impactor around 200 kilometres (120 mi) in diameter during the Late Heavy Bombardment of the early Solar System, approximately 4–3.8 billion years ago, and may be one of the best preserved ancient impact basins from that period. Argyre is surrounded by rugged massifs which form concentric and radial patterns around the basin. Several mountain ranges are present, some of these mountain ranges include Charitum and Nereidum Montes.