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An artist impression of the Mars Reconnaissance Orbiter using its Mars Climate Sounder instrument.

This image was acquired by the High Resolution Imaging Science Experiment (HiRISE) camera aboard MRO on April 18, 2017, at 14:04 local Mars time. This is a crater that has been infilled by material.

Craters on steep hills are not common, partly because rocks falling downhill can quickly erase such craters. Here however, MRO observed a small impact that occurred on the sloping wall of a larger crater and is well-preserved.

MRO image in the Southern hemisphere of Mars. There are shallow pits in the bright residual cap of carbon dioxide ice and a circular formation that penetrates through the ice and dust. This might be an impact crater or it could be a collapse pit.

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An artist impression of the Mars Reconnaissance Orbiter using its Mars Climate Sounder instrument.NASA/JPL-CalTech

This image was acquired by the High Resolution Imaging Science Experiment (HiRISE) camera aboard MRO on April 18, 2017, at 14:04 local Mars time. This is a crater that has been infilled by material that is more resistant to erosion than the rocks around it—surrounded by bluish basaltic dunes.NASA/JPL/University of Arizona

Craters on steep hills are not common, partly because rocks falling downhill can quickly erase such craters. Here however, MRO observed a small impact that occurred on the sloping wall of a larger crater and is well-preserved.NASA/JPL-Caltech/Univ. of Arizona

Mars Reconnaissance Orbiter image in late summer in the Southern hemisphere. The Sun is low in the sky and subtle topography is accentuated. There are shallow pits in the bright residual cap of carbon dioxide ice and a circular formation that penetrates through the ice and dust. This might be an impact crater or it could be a collapse pit.NASA/JPL-Caltech/Univ. of Arizona

Mission name: MRO

Mars Reconnaissance Orbiter

A Mission to Study the History of Water on Mars

Launch Date August 12, 2005
Arrival Date March 10, 2006
Mission TypeOrbiter
TargetMars

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Mission Overview
NASA’s Mars Reconnaissance Orbiter (MRO), launched August 12, 2005, is on a search for evidence that water persisted on the surface of Mars for a long period of time. While other Mars missions have shown that water flowed across the surface in Mars’ history, it remains a mystery whether water was ever around long enough to provide a habitat for life.

Relevance to Astrobiology
Data from MRO is essential to astrobiologists studying the potential for habitable environments on past and present Mars. MRO also provides invaluable data used in selecting landing sites for future Mars missions. Data from MRO is also important in building climate models for Mars, and for use in comparative planetology studies performed astrobiologists who study the potential habitability of exoplanets that orbit distant stars.

NASA Astrobiology Involvement
The NASA Astrobiology Program supports numerous scientists involved in the MRO mission, as well as researchers working with data returned by the orbiter. Being active for more than a decade, MRO has sent back an astounding amount of data that will provide astrobiologists interested in Mars with scientific opportunities for years to come.

The Astrobiologists
Researchers working with data from MRO are supported by the NASA Astrobiology Program through a number of program elements, including Habitable Worlds, Exobiology & Evolutionary Biology, Exoplanets (NExSS), the NASA Astrobiology Institute (NAI) and the instrument development programs PICASSO and MatISSE.

Mission news and discoveries

Artist's concept of the Mars Reconnaissance Orbiter in orbit around the Red Planet.

NASA’s Mars Fleet Will Still Conduct Science While Lying Low (NASA)November 13, 2023

Rosalind Franklin Society Awards Recognize Laurie BargeJuly 27, 2023

New Interactive Mosaic Uses NASA Imagery to Show Mars in Vivid Detail (NASA JPL)April 06, 2023

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Major mission findings

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.

October 06, 2017Ancient Sea-Floor Hydrothermal Deposits

Data from MRO showed that hot springs pumped mineral-laden water directly into an ancient Martian sea on southern Mars. The sea once held nearly 10 times as much water as all of North America’s Great Lakes combined. Undersea hydrothermal conditions on Mars may have existed about 3.7 billion years ago; undersea hydrothermal conditions on Earth at about that same time are a strong candidate for where and when life on Earth began.

MRO captured dark streaks slopes in Hale Crater that are inferred to be formed by seasonal flow of water on present-day Mars. The imaging and topographical information in this processed, false-color view come from the HiRISE camera.

September 28, 2015Possible Brines on Mars

MRO provided the strongest evidence yet that liquid water flows intermittently on present-day Mars. Researchers found signatures of hydrated minerals on slopes where mysterious, dark streaks appear to ebb and flow over time. They darken and appear to flow down steep slopes during warm seasons, and then fade in cooler seasons.

August 04, 2011MRO Suggests Water Flowing On Mars

With repeated observations, MRO found dark, finger-like features that appear and extend down some martian slopes during late spring through summer, fade in winter, and return during the next spring. Repeated observations have tracked the seasonal changes in these recurring features on several steep slopes in the middle latitudes of Mars’ southern hemisphere.

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Mission Facts

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Artist impression of MRO using its Shallow Radar (SHARAD) to "look" under the surface of Mars. The SHARAD instrument seeks liquid or frozen water within the first few hundred feet (up to a kilometer) under the martian surface.

The high resolution imaging science experiment (HiRISE) is one of six science instruments for NASA's Mars Reconnaissance Orbiter. Here, HiRISE is prepared before it is shipped for attachment to the spacecraft.

The CRISM instrument on MRO being prepared before launch.

This artist's concept of NASA's Mars Reconnaissance Orbiter highlights the spacecraft's radar capability. The Shallow Subsurface Radar instrument (SHARAD) includes the long antenna that extends horizontally from the spacecraft.

This map shows the frequency of carbon dioxide frost's presence at sunrise on Mars, as a percentage of days year-round. Color coding is based on data from the Mars Climate Sounder instrument on NASA's Mars Reconnaissance Orbiter.

A color-enhanced image of the delta in Jezero Crater, which once held a lake. Ancient rivers ferried clay-like minerals (shown in green) into the lake, forming the delta.

This image shows carbon dioxide ice on the south polar caps of Mars. The features are high-standing mesas, with carbon dioxide material filling in the low areas between them.

Goal 1: Water on MarsThe presence of past or present liquid water on Mars is a key to understanding the potential for life.

MRO has instruments to study water-related surface features, water-related mineral deposits, and a sounder to search for liquid or frozen water up to a kilometer beneath the martian surface.

Three CamerasHiRISE (High Resolution Imaging Science Experiment); CTX (Context Camera); MARCI (Mars Color Imager)

Among its six instruments, MRO carries three cameras. This includes the visual camera HiRISE (shown), which has returned invaluable data about the martian surface.

SpectrometerCRISM (Compact Reconnaissance Imaging Spectrometer for Mars)

This instrument splits visible and near-infrared light in its images into hundreds of “colors” that identify minerals, especially those likely formed in the presence of water, in surface areas on Mars not much bigger than a football field.

RadarSHARAD (Shallow Radar)

This sounding radar probes beneath the Martian surface to find geologic boundaries and ice at depths greater than ~33 feet (10 meters).

RadiometerMCS (Mars Climate Sounder)

This atmospheric profiler detects vertical variations in temperature, dust, and water vapor concentrations in the Martian atmosphere.

Goal 3: Characterize the Geology of MarsA record of Mars' history

MRO looks for geologic settings that indicate the presence of liquid water on the Mars surface at some point in the planet’s history. Examples include ancient lakebeds, salt flats, and mineral deposits characteristic of hot springs.

Goal 2: Characterize the Climate of MarsWater and the Mars climate

MRO studies ice or liquid water beneath the surface and the subsurface structure of the polar caps and nearby terrain in search of evidence of the role water played in Mars’ past climate. MRO also studies dust and water are transport in the atmosphere.

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Controlling the rover from Earth, scientists drive the rover along Mars' surface inspecting geological features. Credit: NASA/JPL

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