Valles Marineris, a Martian rift zone named to honor the scientific team of the Mariner 9 program

The Valles Marineris got their name in 1973 to honor the scientific team of the Mariner 9 program [1]. The term “Valles Marineris” is the latinized form of the phrase “Mariner Valleys.” “Valles” is the plural form of the Latin noun “vallis.” The plural form in “Valles Marineris” indicates that this vast Martian surface feature is a system of multiple valleys or canyons.

Valles Marineris was discovered in 1972 by the Mariner 9 spacecraft [3]: Its length matches the distance between New York City and Los Angeles. This valley system, commonly referred to as the Valles Marineris trough system, is located close to the Martian equator, where it trends east-west from longitude 40°W to 110°W with a depth reaching 10 km [4]. During NASA's Global Surveyor Mission, the deepest point was found by laser measurements within the valleys in the Coprates Chasma region [5,6]: Valles Marineris does not exhibit the typical features of a river bed or canyon formed by water flowing down from source to delta. A complete understanding of how the Valles Marineris system originated and evolved by combination of water flow, magmatic processes, tensional fracturing and/or other forces is still far away.  

Keywords: astronomy, planetary science, areography, Martian topography, Latin, vallis, valles, terminology.

References and more to explore
[1] Google Mars Lab: www.google.com/mars.
[2] Glossary of Latin Words > V: www.bible-history.com/latin/latin_v.html.
[3] Valles Marineris, a Martian Rift Zone: themis.asu.edu/feature/16.
[4] Géomorphologie > New insight on genetic links between outflows and chasmata on Valles Marineris plateau, Mars (January 2009): geomorphologie.revues.org/7485.
[5] ESA Mars Express > Coprates Chasma and Coprates Catena: www.esa.int/esaMI/Mars_Express/SEMIRE1DU8E_0.html.
[6] Ulf von Rauchhaupt: Der Neunte Kontinent - Die wissenschaftliche Eroberung des Mars. Fischer Taschenbuch Verlag, Frankfurt am Main, November 2010; pages 114 to 119.