This image from NASA's 2001 Mars Odyssey spacecraft shows part of the margin of the north polar cap and the surrounding plains. The layering of the ice is easily visible due to the dust that is deposited on the top of the ice every year, creating layering over millions of years.
This image combines two products from the first pointing at the Martian moon Phobos by the THEMIS camera on NASA's Mars Odyssey orbiter, on Sept. 29, 2017. Surface-temperature information from observation in thermal-infrared wavelengths is overlaid on a more detailed image from a visible-light observation.
This image of Phobos is one product of the first pointing at that Martian moon by the THEMIS camera on NASA's Mars Odyssey orbiter. The Sept. 29, 2017, observation also provided information about temperatures on different areas of Phobos. The oblong moon has an average diameter of about 14 miles.
This series of images was taken in visible-wavelength light as the THEMIS camera on NASA's Mars Odyssey scanned across the Martian moon Phobos on Sept. 29, 2017. The apparent motion is due to progression of the camera's pointing during 18 seconds of observing, not from motion of Phobos.
Colors in this image of the Martian moon Phobos indicate a range of surface temperatures detected by observing the moon on Sept. 29, 2017, with the Thermal Emission Imaging System (THEMIS) camera on NASA's Mars Odyssey orbiter.
Re-analysis of 2002-2009 data from a hydrogen-finding instrument on NASA's Mars Odyssey orbiter increased the resolution of maps of hydrogen abundance. The reprocessed data (lower map) shows more "water-equivalent hydrogen" (darker blue) in some parts of this equatorial region of Mars.
Valleys much younger than well-known ancient valley networks on Mars are evident near the informally named "Heart Lake" on Mars. This map presents color-coded topographical information overlaid onto a photo mosaic. Lower elevations are indicated with white and purple; higher elevations, yellow.
At 11:02 a.m. EDT on April 7, 2001, crowds watch a Boeing Delta II rocket lift off from Cape Canaveral Air Force Station, Florida, carrying NASA's 2001 Mars Odyssey spacecraft into space on its seven-month journey to Mars.
Morning clouds fill Coprates Chasma on Mars in this Nov. 25, 2015, image from the THEMIS camera on NASA's Mars Odyssey. No orbiter systematically observed Mars in morning sunlight before 2015. The clouds appear blue because ice particles in them scatter blue light more strongly than other colors.
This map shows unprecedented detail of local variations in Mars' gravitational pull on orbiters. The gravitational mapping has been applied to map variations in the thickness of the planet's crust and to deduce information about its deeper interior.
Newly detailed mapping of local variations in Mars' gravitational pull on orbiters (center), combined with topographical mapping of the planet's mountains and valleys (left), yields the best-yet mapping of Mars' crustal thickness (right).
This view combines information from two instruments on NASA's Mars Reconnaissance Orbiter to map color-coded composition over the shape of the ground in a small portion of the Nili Fossae plains region of Mars' northern hemisphere.
Seen shortly after local Martian sunrise, clouds gather in the summit pit, or caldera, of Pavonis Mons, a giant volcano on Mars, in this image from the Thermal Emission Imaging System (THEMIS) on NASA's Mars Odyssey orbiter.
This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet's two natural satellites. It illustrates the potential for intersections of the spacecraft orbits.
This artist's concept shows NASA's Mars orbiters lining up behind the Red Planet for their "duck and cover" maneuver to shield them fro comet dust that may result from the close flyby of comet Siding Spring (C/2013 A1) on Oct. 19, 2014. Credit: NASA/JPL-Caltech
NASA's NEOWISE mission detected comet C/2013 A1 Siding Spring on July 28, 2014, less than three months before this comet's close flyby of Mars on Oct. 19. This merging of multiple images presents the comet in four different positions relative to the background stars.
This false-color map shows the area within Gale Crater on Mars, where NASA's Curiosity rover landed on Aug. 5, 2012 PDT (Aug. 6, 2012 EDT) and the location where Curiosity collected its first drilled sample at the "John Klein" rock.
This mosaic image of Valles Marineris - colored to resemble the martian surface - comes from the Thermal Emission Imaging System (THEMIS), a visible-light and infrared-sensing camera on NASA's Mars Odyssey orbiter.
Echus Chasma forms the boundary between the Tharsis volcanoes to the west and Lunae Planum to the east. This region is one of both tectonically fractured rocks (top of image) and volcanic flows (middle and bottom of image). Echus Chasma empties into Kasei Valles.
Just as on Earth, volcanism and tectonism are found together on Mars. Here is an example: the ridges and fractures of Claritas Fossae are affecting or perhaps hosting the volcanic flows of Solis Planum.
Valles Marineris, the "Grand Canyon of Mars," sprawls wide enough to reach from Los Angeles to nearly New York City, if it were located on Earth. The red outline box shows the location of a second, full-resolution image.
Sixteen seventh-graders at Evergreen Middle School in Cottonwood, Calif., found the Martian pit feature at the center of the superimposed red square in this image while participating in a program that enables students to use the camera on NASA's Mars Odyssey orbiter.
Stages in the seasonal disappearance of surface ice from the ground around the Phoenix Mars Lander are visible in these images taken on Feb. 8, 2010, (left) and Feb. 25, 2010, during springtime on northern Mars.
NASA's Phoenix Mars Lander, its backshell and its heatshield are visible within this enhanced-color image of the Phoenix landing site taken on Jan. 6, 2010 by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.