On the northern side of Valles Marineris on Mars lies a closed geological depression named Hebes Chasma. In outline, Hebes looks like a micro-version of the gigantic valley - but it extends only about 320 kilometers (200 miles) long and stretches 130 km (80 miles) wide at its widest. Still, Hebes is about 5 to 6 km (16,000 to 20,000 feet) deep in the region seen here and as with most parts of the Valles Marineris system, landslides scar its walls.

Yet Hebes isn't simply a tiny sibling. Much of its interior is filled with a large mesa measuring about 120 km (75 miles) long by 40 km (25 miles) wide. The mesa's top reaches nearly as high as the surrounding terrain. No other Martian canyon has a similar feature.

This false-color image was made from frames taken by the Thermal Emission Imaging System (THEMIS), a camera that views Mars in 5 visual and 10 infrared "colors." THEMIS orbits aboard NASA's Mars Odyssey spacecraft.