In this beautiful VIS image, taken by the NASA - Mars Odyssey Orbiter on February, 28th, 2015, and during its 58.592nd orbit around the Red Planet, we can see a really small part of the large Dunefield located on the Floor of Proctor Crater.
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 (probably made of Basaltic Sand) 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 and, just out of curiosity, Proctor's Dunes are still being monitored by several Spacecrafts now orbiting the Red Planet with the aim of identifying the changes (if any) which might have occurred - over time - in the shape of the Dunefield itself.
Latitude (centered): 47,5967° South
Longitude (centered): 30,0732° East
This image (which is an Original Mars Odyssey Orbiter falsely colored and Map Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 20074) has been additionally processed, magnified to aid the visibility of the details, extra-contrast enhanced and sharpened, Gamma corrected and then re-colorized in Absolute Natural Colors (such as the colors that a normal 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.