meridiani planum

This image, acquired on Nov. 24, 2015 by theHigh Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter, shows the western side of an elongated pit depression in the eastern Noctis Labyrinthus region of Mars. Along the pit’s upper wall is a light-toned layered deposit. Noctis Labyrinthus is a huge region of tectonically controlled valleys located at the western end of the Valles Marineris canyon system.

Spectra extracted from the light-toned deposit by the spacecraft’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument are consistent with the mineral jarosite, which is a potassium and iron hydrous sulfate. On Earth, jarosite can form in ore deposits or from alteration near volcanic vents, and indicates an oxidizing and acidic environment. The Opportunity rover discovered jarosite at the Meridiani Planum landing site, and jarosite has been found at several other locations on Mars, indicating that it is a common mineral on the Red Planet.

The jarosite-bearing deposit observed here could indicate acidic aqueous conditions within a volcanic system in Noctis Labyrinthus. Above the light-toned jarosite deposit is a mantle of finely layered darker-toned material. CRISM spectra do not indicate this upper darker-toned mantle is hydrated. The deposit appears to drape over the pre-existing topography, suggesting it represents an airfall deposit from either atmospheric dust or volcanic ash.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA’s Science Mission Directorate, Washington.

Credit: NASA/JPL-Caltech/Univ. of Arizona/ Mars Reconnaissance Orbiter

Caption: Cathy Weitz

Time And Space

‘Victoria Crater’ at Meridiani Planum

This image from the High Resolution Imaging Science Experiment on NASA’s Mars Reconnaissance Orbiter shows “Victoria crater,” an impact crater at Meridiani Planum, near the equator of Mars. The crater is approximately 800 meters (half a mile) in diameter. It has a distinctive scalloped shape to its rim, caused by erosion and downhill movement of crater wall material. Layered sedimentary rocks are exposed along the inner wall of the crater, and boulders that have fallen from the crater wall are visible on the crater floor. The floor of the crater is occupied by a striking field of sand dunes.

Since January 2004, the Mars Exploration Rover Opportunity has been operating at Meridiani Planum. Five days before this image was taken, Opportunity arrived at the rim of Victoria crater, after a drive of more than 9 kilometers (over 5 miles). The rover can be seen in this image, at roughly the “ten o'clock” position along the rim of the crater.

Image credit: NASA/JPL-Caltech/University of Arizona/Cornell/Ohio State University