Countdown Nears: Final Tests

A comparison of two radargrams from the SHARAD instrument on NASA's Mars Reconnaissance Orbiter shows effects on the Martian ionosphere from the close passage of a comet.

This is a diagram that shows the launch phases for the Mars Reconnaissance Orbiter.

This observation from NASA's Mars Reconnaissance Orbiter shows a sand dune field in the Nili Fossae region of Mars. The dark lines swirling over the surface of the dunes are the tracks of dust devi...

Interact with this 3D model of the Mars Reconnaissance Orbiter.

NASA’s InSight has been busy. After landing on the Red Planet, the mission sent home pictures and sound, then placed its first instrument on the planet's surface. Plus, find out what the Curiosity ...

Mars Reconnaissance Orbiter is Off to Mars!

This unnamed impact crater is about 8 kilometers in diameter and contains numerous gullies.

Two types of wind-blown sedimentary deposits are pictured in this scene of the floor of Ius Chasma in the Valles Marineris.

This sequence of seven images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter shows wind-caused changes in the parachute of NASA's Mars Sci...

This enhanced image shows the inside of a rimless pit about 180 meters (591 feet) in diameter, northwest of the mountain Ascraeus Mons in the northern hemisphere of Mars.

In February 2015, NASA's Mars Exploration Rover Opportunity is approaching a cumulative driving distance on Mars equal to the length of a marathon race. This map shows the rover's position relative...

The rock layers in this image were likely horizontal when the materials were first deposited, but are now tilted to high angles, approaching 90 degrees.

An image combining orbital imagery with 3-D modeling shows flows that appear in spring and summer on a slope inside Mars' Newton crater.

This image is of a portion of the Southern plains region within Hellas, the largest impact basin on Mars, with a diameter of about 2300 kilometers (1400 miles).

The High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter acquired this color image on March 9, 2011, of "Santa Maria" crater, showing NASA's Mars Explora...

These examples of one distinctive type of Martian gullies, called "linear gullies," are on a dune in Matara Crater, seen at different times of year to observe changes.

It's not only when trying to find a scientifically interesting place to land that the high-resolution images from HiRISE come in handy: it's also to identify potential hazards within a landing elli...

This image shows the context for orbital observations of exposed rocks that had been buried an estimated 5 kilometers (3 miles) deep on Mars.

These long, smooth features are sand ridges shaped by the constant martian wind. They run perpendicular, or at right angles to, the direction of the wind and often found in channels and crater inte...

This fresh crater is located in the northern mid-latitudes. It is designated as fresh because of its very sharp rim.

The white arrows indicate locations in this scene where numerous seasonal dark streaks, called "recurring slope lineae," have been identified in the Coprates Montes area of Mars' Valles Marineris b...

This image from the NASA Mars Reconnaissance Orbiter shows an impact scar on Mars made by pieces of the NASA Mars Science Laboratory spacecraft that the spacecraft shed just before entering the Mar...

This April 6, 2014, image from the Context Camera on NASA's Mars Reconnaissance Orbiter was taken as a follow-up to discovery of a possible 2012 impact scar in images from the orbiter's Mars Color ...

Recurring slope lineae (RSL) are active flows on warm Martian slopes that might be caused by seeping water.

This graphic shows the route that NASA's Mars Exploration Rover Opportunity drove in its final approach to "Perseverance Valley" on the western rim of Endeavour Crater during spring 2017.