In this VIS image, taken by the NASA - Mars Odyssey Orbiter on July 4th, 2013, and during its 51.257th orbit around the Red Planet, we can see part of the very large Dunefield that is located located on the Floor of Proctor Crater (a large Impact Crater found in the Noachis Quadrangle of Mars, at about 48° South Latitude and 330,5° West Longitude).
Proctor Crater is approx. 168 Km (such as about 104,3 miles) in diameter and it was so named after Dr Richard A. Proctor, a British Astronomer (who was born in Chelsea - London, UK, on March, 23rd, 1837 and died in New York - USA - on September, 12th, 1888). Proctor Crater contains an approx. 35 x 65 Km (such as about 21,7 x 40,36 miles) Dark Dunefield that was one of the first Sand Dunefields ever recognized on Mars - note: this discovery was based on the NASA - Mariner 9 Spacecraft's images. Just out of curiosity, Proctor's Dunes are still being monitored by several Spacecrafts now orbiting the Red Planet (including the NASA- Mars Reconnaissance Orbiter) with the aim of identifying the changes (if any) which might have occurred - over time - in the shape of the Dunefield itself.
Latitude (centered): 47,4158° South
Longitude (centered): 30,9423° East
This frame (taken from an Original Mars Odyssey Orbiter b/w and Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 17421) has been additionally processed, magnified, contrast enhanced, Gamma corrected and then colorized in Absolute Natural Colors (such as the colors that a human eye would actually perceive if someone were onboard the NASA - Mars Odyssey Orbiter and then looked down, towards the Surface of Mars), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.