This image from NASA's Mars Reconnaissance Orbiter shows one of these exotic locales at the South Pole. The polar cap is made from carbon dioxide (dry ice). The circular pits are holes in this dry ice layer that expand by a few meters each Martian year.
Location of Large Subsurface Water-Ice Deposit in Utopia Planitia, Mars
Diagonal striping on this map of a portion of the Utopia Planitia region on Mars indicates the area where a large subsurface deposit rich in water ice was assessed using the Shallow Radar instrument on NASA's Mars Reconnaissance Orbiter.
These two images show Shallow Radar instrument data from two tracks in a part of Mars' Utopia Planitia region where the orbiting, ground-penetrating radar on NASA's Mars Reconnaissance Orbiter detected subsurface deposits rich in water ice.
Scalloped Terrain Led to Finding of Buried Ice on Mars
This vertically exaggerated view shows scalloped depressions in Mars' Utopia Planitia region, prompting the use of ground-penetrating radar aboard NASA's Mars Reconnaissance Orbiter to check for underground ice.
Exposed Fractured Bedrock in the Central Pit of a Crater
This image from NASA's Mars Reconnaissance Orbiter shows the central pit feature of an approximately 20-km diameter complex crater in located just north of the Valles Marineris. A partial ring of light-toned, massive and fractured bedrock is observed.
This area of Amazonis Planitia to the west of the large volcano Olympus Mons was once flooded with lava as seen by NASA's Mars Reconnaissance Orbiter. A huge eruption flowed out across the relatively flat landscape.
On Nov. 1, 2016, the High Resolution Imaging Science ExperNASA's Mars Reconnaissance Orbiter observed the impact site of Europe's Schiaparelli test lander, gaining the first color view of the site since the lander's Oct. 19, 2016, arrival.
This image from NASA's Mars Reconnaissance Orbiter shows one of two spots that likely appeared in connection with the Oct. 19, 2016, arrival of ESA's Schiaparelli test lander. An animation is available at the Photojournal.
Martian 'Spiders' in Sharper Look, Thanks to Volunteers
This image from NASA's Mars Reconnaissance Orbiter shows spidery channels eroded into Martian ground. This terrain type, called spiders or 'araneiform' (from the Latin word for spiders), appears in some areas of far-southern Mars.
This image from NASA's Mars Reconnaissance Orbiter shows some beautiful lava flows in Amazonis Planitia. Lava isn't moving around on Mars today, but it certainly once did, and images like this one are evidence of that.
The Tharsis region of Mars is covered in vast lava flows, many with channels, as seen by NASA's Mars Reconnaissance Orbiter. Some channels, however, resemble features that may have been formed by water.