Artist concept of Mars Reconnaissance Orbiter

This sinuous raised ridge is thought to be an inverted stream channel.  These are formerly low-lying streambeds that became elevated because the original depression is filled with materials (such a...

This view of a portion of the Eridania region of Mars shows blocks of deep-basin deposits that have been surrounded and partially buried by younger volcanic deposits. The image was taken by the Con...

The Mars Climate Sounder, an instrument on NASA's Mars Reconnaissance Orbiter designed to monitor daily changes in the global atmosphere of Mars, made its first observations of Mars on March 24, 2006.

With the spacecraft safely captured into orbit, the Mars Reconnaissance Orbiter team transitions to the next critical phase -- aerobraking. Learn how engineers slow the spacecraft and precisely sha...

This image shows the transitional terrain where the linear troughs and rounded pits of an area called "Noctis Labyrinthus" merge with the larger canyon of "Valles Marineris." Unusual bright blocks ...

This observation shows a wrinkle ridge in Solis Planum, located in the Thaumasia region of Mars, a high-elevation volcanic plain located south of the Valles Marineris canyon system and east of the ...

Athabasca Valles is a large channel carved by giant outbursts of groundwater somewhere between 2 and 30 million years ago. These streamlined "islands" were carved by the massive floodwaters.

Countdown Nears: Final Tests

This image acquired on October 5, 2018 by NASAs Mars Reconnaissance Orbiter, shows a new impact crater that formed between July and September 2018.

Mars's seasonal polar caps are composed primarily of carbon-dioxide frost.

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 Sidi...

Three pairs of before and after images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter illustrate movement of ripples on dark sand dunes in...

This global map of Mars was acquired on Aug. 4, 2012, by the Mars Color Imager instrument on NASA's Mars Reconnaissance Orbiter.

The High Resolution Imaging Science Experiment (HiRISE) camera would make a great backyard telescope for viewing Mars, and we can also use it at Mars to view other planets. This is an image of Eart...

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 ...

This is an image of Gusev Crater taken by the Mars Reconnaissance Orbiter HiRISE camera and is one of the potential landing sites for the Mars 2020 rover.

Mars has extremely large temperature changes from winter to summer compared to the Earth. It gets cold enough to freeze carbon dioxide out of the atmosphere during the winter, but this ice is unsta...

A small channel cuts across the floor of a gigantic 1100-mile (1780-kilometer)-long set of flood-carved channels in a region on Mars called "Kasei Valles."

This stereo view shows an area on Mars where narrow rock ridges intersect at angles forming corners of polygons. It combines two observations from the HiRISE camera on NASA's Mars Reconnaissance Or...

Images acquired Jan. 9, 2022, from the Mars Color Imager instrument on NASA’s Mars Reconnaissance Orbiter were combined to create this view showing the presence of a regional dust storm obscuring t...

The Mars Color Imager test view looks northward and includes the large Argyre Basin in Mars' southern hemisphere.

Mawrth Vallis contains clay minerals that formed by chemical alteration of rocks by water. The central part of the image is dominated by light-toned materials with curving fractures of many differe...

Dark, narrow streaks on Martian slopes such as these at Horowitz Crater are inferred to have been formed by seasonal flow of water on contemporary Mars. Detection of hydrated salts at the streaks s...

Stokes Crater, pictured here, is one of at least nine craters in the northern lowlands of Mars with exposures of hydrated minerals detected from orbit, according to a June 25, 2010, report.

This image from NASA's Mars Reconnaissance Orbiter (MRO) shows the western wall of a small pit that is located along the floor of a larger trough in Coprates Catena. Dark layers line the bottom; li...