Space Missions

New NASA Mission to Study Ocean Color, Airborne Particles and Clouds

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New measurements by NASA’s PACE spacecraft will advance our understanding of how living marine resources respond to a changing climate. NASA pioneered the field of global ocean color observations with the SeaWIFS satellite sensor from 1997 to 2010. Image Credit: NASA


(PRESS RELEASE): NASA is beginning work on a new satellite mission that will extend critical climate measurements of Earth’s oceans and atmosphere and advance studies of the impact of environmental changes on ocean health, fisheries and the carbon cycle.

Tentatively scheduled to launch in 2022, the Pre-Aerosol Clouds and ocean Ecosystem (PACE) mission will study Earth’s aquatic ecology and chemistry, and address the uncertainty in our understanding of how clouds and small airborne particles called aerosols affect Earth’s climate. PACE will be managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

“Knowing more about global phytoplankton community composition will help us understand how living marine resources respond to a changing climate,” said Jeremy Werdell, PACE project scientist at Goddard. “With PACE, we will learn more about the role of marine phytoplankton in the global carbon cycle.”

NASA has long used satellites to observe the global ocean’s microscopic algal communities, which play a significant role in the ocean’s ecology and the global carbon cycle. PACE will provide a global view of the planet’s microscopic ocean algae called phytoplankton. Phytoplankton live in the sunlit upper layer of the ocean, producing at least half of the oxygen on Earth and form the base of the marine food chain.

Goddard will build PACE’s ocean color instrument. This PACE sensor will allow scientists to see the colors of the ocean, from the ultraviolet to near infrared, and obtain more accurate measurements of biological and chemical ocean properties, such as phytoplankton biomass and the composition of phytoplankton communities. These changes in the ocean’s color help identify harmful algal blooms.

Quantifying phytoplankton is essential for understanding the carbon cycle and tracking climate variability and change. The ocean absorbs atmospheric carbon dioxide into solution at the sea surface. Like land plants, phytoplankton use carbon dioxide to create their organic biomass via photosynthesis. Phytoplankton vary greatly in their size, function, and response to environmental and ecosystem changes or stresses such as ocean acidification.

Dissolved carbon dioxide also reacts with seawater and alters its acidity. About one fourth of human-made carbon dioxide ends up in the ocean.

“NASA Goddard pioneered ocean color remote sensing 35 years ago with the very first satellite observations, and the Center has been committed to supporting the science ever since,” said Piers Sellers, deputy director of NASA Goddard Earth Science. “Goddard scientists play a critical role in generating and improving core satellite data sets for the international ocean biology community. We look forward to extending this important record into the future with PACE.”

In addition to gathering data on ocean color, PACE will measure clouds and tiny airborne particles like dust, smoke and aerosols in the atmosphere to supplement measurements from existing NASA satellite missions. These measurements are critical for understanding the flow of natural and human made aerosols in the environment. Aerosols affect how energy moves in and out of Earth’s atmosphere directly by scattering sunlight, and indirectly by changing the composition of clouds. Aerosols also can affect the formation of precipitation in clouds and change rainfall patterns.

The blend of atmospheric and oceanic observations from PACE is critical as ocean biology is affected by aerosols deposited onto the ocean, which in turn, produce aerosol precursors that influence atmospheric composition and climate. NASA is currently planning a second PACE instrument, a polarimeter, to better measure aerosol and cloud properties. These measurements will improve understanding of the roles of aerosols in the climate system.

Goddard’s proof-of-concept sensor for measuring ocean color — the Coastal Zone Color Scanner that flew on the Nimbus-7 satellite from 1978 to 1986 — was the first sensor to demonstrate phytoplankton biomass could be quantified from space. The Sea-Viewing Wide Field-of-View Sensor or SeaWiFS mission collected data from 1997 to 2010 and was the first mission dedicated to routinely observe ocean biology, chemistry, and ecology for long-term climate research. Currently, researchers employ the Moderate Resolution Imaging Spectroradiometer that flies aboard both NASA’s Terra and Aqua spacecraft, and the Visible Infrared Imager Radiometer Suite aboard the NASA-NOAA Suomi National Polar-orbiting Partnership satellite, to measure biological and chemical properties of the ocean, as well as aerosol and cloud properties.

NASA capped the costs for PACE at $805 million, to cover the spacecraft, mission design and engineering, science, instruments, launch vehicle, data processing, and operations.

For more information about PACE, visit:

http://decadal.gsfc.nasa.gov/pace.html

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

For more information on NASA’s Earth science activities, visit:

www.nasa.gov/earthrightnow

JPL: Saturn Moon’s Ocean May Harbor Hydrothermal Activity

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This cutaway view of Saturn’s moon Enceladus is an artist’s rendering that depicts possible hydrothermal activity that may be taking place on and under the seafloor of the moon’s subsurface ocean, based on recently published results from NASA’s Cassini mission.


Spacecraft Data Suggest Saturn Moon’s Ocean May Harbor Hydrothermal Activity

Fast Facts:

› Cassini finds first evidence of active hot-water chemistry beyond planet Earth

› Findings in two separate papers support the notion

› The results have important implications for the habitability of icy worlds

NASA’s Cassini spacecraft has provided scientists the first clear evidence that Saturn’s moon Enceladus exhibits signs of present-day hydrothermal activity which may resemble that seen in the deep oceans on Earth. The implications of such activity on a world other than our planet open up unprecedented scientific possibilities.

“These findings add to the possibility that Enceladus, which contains a subsurface ocean and displays remarkable geologic activity, could contain environments suitable for living organisms,” said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington. “The locations in our solar system where extreme environments occur in which life might exist may bring us closer to answering the question: are we alone in the universe.”

Hydrothermal activity occurs when seawater infiltrates and reacts with a rocky crust and emerges as a heated, mineral-laden solution, a natural occurrence in Earth’s oceans. According to two science papers, the results are the first clear indications an icy moon may have similar ongoing active processes.

The first paper, published this week in the journal Nature, relates to microscopic grains of rock detected by Cassini in the Saturn system. An extensive, four-year analysis of data from the spacecraft, computer simulations and laboratory experiments led researchers to the conclusion the tiny grains most likely form when hot water containing dissolved minerals from the moon’s rocky interior travels upward, coming into contact with cooler water. Temperatures required for the interactions that produce the tiny rock grains would be at least 194 degrees Fahrenheit (90 degrees Celsius).

“It’s very exciting that we can use these tiny grains of rock, spewed into space by geysers, to tell us about conditions on — and beneath — the ocean floor of an icy moon,” said the paper’s lead author Sean Hsu, a postdoctoral researcher at the University of Colorado at Boulder.

Cassini’s cosmic dust analyzer (CDA) instrument repeatedly detected miniscule rock particles rich in silicon, even before Cassini entered Saturn’s orbit in 2004. By process of elimination, the CDA team concluded these particles must be grains of silica, which is found in sand and the mineral quartz on Earth. The consistent size of the grains observed by Cassini, the largest of which were 6 to 9 nanometers, was the clue that told the researchers a specific process likely was responsible.

On Earth, the most common way to form silica grains of this size is hydrothermal activity under a specific range of conditions; namely, when slightly alkaline and salty water that is super-saturated with silica undergoes a big drop in temperature.

“We methodically searched for alternate explanations for the nanosilica grains, but every new result pointed to a single, most likely origin,” said co-author Frank Postberg, a Cassini CDA team scientist at Heidelberg University in Germany.

Hsu and Postberg worked closely with colleagues at the University of Tokyo who performed the detailed laboratory experiments that validated the hydrothermal activity hypothesis. The Japanese team, led by Yasuhito Sekine, verified the conditions under which silica grains form at the same size Cassini detected. The researchers think these conditions may exist on the seafloor of Enceladus, where hot water from the interior meets the relatively cold water at the ocean bottom.

The extremely small size of the silica particles also suggests they travel upward relatively quickly from their hydrothermal origin to the near-surface sources of the moon’s geysers. From seafloor to outer space, a distance of about 30 miles (50 kilometers), the grains spend a few months to a few years in transit, otherwise they would grow much larger.

The authors point out that Cassini’s gravity measurements suggest Enceladus’ rocky core is quite porous, which would allow water from the ocean to percolate into the interior. This would provide a huge surface area where rock and water could interact.

The second paper, recently published in Geophysical Research Letters, suggests hydrothermal activity as one of two likely sources of methane in the plume of gas and ice particles that erupts from the south polar region of Enceladus. The finding is the result of extensive modeling to address why methane, as previously sampled by Cassini, is curiously abundant in the plume.

The team found that, at the high pressures expected in the moon’s ocean, icy materials called clathrates could form that imprison methane molecules within a crystal structure of water ice. Their models indicate that this process is so efficient at depleting the ocean of methane that the researchers still needed an explanation for its abundance in the plume.

In one scenario, hydrothermal processes super-saturate the ocean with methane. This could occur if methane is produced faster than it is converted into clathrates. A second possibility is that methane clathrates from the ocean are dragged along into the erupting plumes and release their methane as they rise, like bubbles forming in a popped bottle of champagne.

The authors agree both scenarios are likely occurring to some degree, but they note that the presence of nanosilica grains, as documented by the other paper, favors the hydrothermal scenario.

“We didn’t expect that our study of clathrates in the Enceladus ocean would lead us to the idea that methane is actively being produced by hydrothermal processes,” said lead author Alexis Bouquet, a graduate student at the University of Texas at San Antonio. Bouquet worked with co-author Hunter Waite, who leads the Cassini Ion and Neutral Mass Spectrometer (INMS) team at Southwest Research Institute in San Antonio.

Cassini first revealed active geological processes on Enceladus in 2005 with evidence of an icy spray issuing from the moon’s south polar region and higher-than-expected temperatures in the icy surface there. With its powerful suite of complementary science instruments, the mission soon revealed a towering plume of water ice and vapor, salts and organic materials that issues from relatively warm fractures on the wrinkled surface. Gravity science results published in 2014 strongly suggested the presence of a 6-mile- (10-kilometer-) deep ocean beneath an ice shell about 19 to 25 miles (30 to 40 kilometers) thick.

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the mission for the agency’s Science Mission Directorate in Washington. The Cassini CDA instrument was provided by the German Aerospace Center. The instrument team, led by Ralf Srama, is based at the University of Stuttgart in Germany. JPL is a division of the California Institute of Technology in Pasadena.

More information about Cassini, visit:

http://www.nasa.gov/cassini

and

http://saturn.jpl.nasa.gov

NASA: Bangladesh Announces Nationwide Use of SERVIR Satellite-based Flood Forecasting and Warning System

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Upper row: The Ganges Brahmaputra Meghna (GBM) river basins and the Ganges-Brahmaputra (GB) delta. Bottom row: The many river deltas (shown as a triangle in each region) located in large remote river basins that lack information for modeling rivers and water management. Image Credit: NASA SERVIR

Bangladesh officials have announced plans to expand a satellite-based flood forecasting and warning system developed by SERVIR to aid an area where floodwaters inundate from 1/3 to 2/3 of the country annually, killing hundreds of people and affecting millions. The system, which relies on river level data provided by the Jason-2 satellite, last year provided the longest lead time for flood warnings ever produced in Bangladesh.

SERVIR is a joint development initiative of NASA and USAID, working in partnership with leading regional organizations around the globe to help developing countries use information provided by Earth Observing satellites and geospatial technologies for managing climate risks and land use. SERVIR and the International Centre for Integrated Mountain Development based in Kathmandu, Nepal, developed the Jason-2 based flood forecasting and warning solution.

“Forecasters have the dream to extend lead time for flood warnings,” said Amirul Hossain, executive engineer for the Bangladesh Water Development Board. “By using Jason-2 near real-time data, we made a real step forward in the flood forecasting system in Bangladesh.”

About 80 million people depend on the BWDB Flood Forecasting and Warning Center flood warnings. This organization has progressively built and expanded its flood forecasting system. However, without data from Jason-2, warnings were issued just three to five days in advance of flooding. During the 2014 monsoon season, the FFWC used the new Jason-2 solution experimentally and was able to forecast flooding eight days in advance at nine locations of the Ganges and Brahmaputra River Basins in the north, northwest, and central part of the country.

SERVIR Applied Sciences Team member Faisal Hossain developed the new system. Hossain and the International Centre for Integrated Mountain Development trained FFWC officials to use it. FFWC quickly FFWC mastered use of the system and became completely independent in using the satellite technology and processing tools, generating warnings at several locations inside Bangladesh.

Jason-2’s radar altimeter measures the precise distance between the satellite and the river surface at points where the satellite crosses overhead. The data, available almost immediately, reveals the river’s height at the point of crossing, so flood risks downstream can be assessed.

Based on the new solution’s successes, FFWC officials announced their intention to expand Jason-2 based forecasting system nation-wide in Bangladesh for 2015.

“We hope this is the beginning of a new journey, a new era for further development of the flood early warning system using space data or space technology,” said Hossain. “In the coming year, with support provided by the NASA SERVIR team, we would like to expand the system to many other locations where possible, to enable more people to benefit from this system by receiving more extended lead time for flood forecasts.”

The SERVIR project operates via regional “hubs” in Nairobi, Kenya; Kathmandu, Nepal; and Bangkok, Thailand. The coordination office for SERVIR is located at NASA’s Marshall Space Flight Center in Huntsville, Alabama.

For more information about SERVIR, visit:

http://www.nasa.gov/mission_pages/servir/

https://www.servirglobal.net/

Janet Anderson
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
janet.l.anderson

NASA Spacecraft Becomes First to Orbit a Dwarf Planet

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NASA Spacecraft Becomes First to Orbit a Dwarf Planet

Latest News From NASA’s Jet Propulsion Laboratory

NASA’s Dawn spacecraft has become the first mission to achieve orbit around a dwarf planet. The spacecraft was approximately 38,000 miles (61,000) kilometers from Ceres when it was captured by the dwarf planet’s gravity at about 4:39 a.m. PST (7:39 a.m. EST) Friday.Mission controllers at NASA’s Jet Propulsion Laboratory in Pasadena, California received a signal from the spacecraft at 5:36 a.m. PST (8:36 a.m. EST) that Dawn was healthy and thrusting with its ion engine, the indicator Dawn had entered orbit as planned.

“Since its discovery in 1801, Ceres was known as a planet, then an asteroid and later a dwarf planet,” said Marc Rayman, Dawn chief engineer and mission director at JPL. “Now, after a journey of 3.1 billion miles (4.9 billion kilometers) and 7.5 years, Dawn calls Ceres, home.”

In addition to being the first spacecraft to visit a dwarf planet, Dawn also has the distinction of being the first mission to orbit two extraterrestrial targets. From 2011 to 2012, the space-craft explored the giant asteroid Vesta, delivering new insights and thousands of images from that distant world. Ceres and Vesta are the two most massive residents of our solar system’s main asteroid belt between Mars and Jupiter.

The most recent images received from the spacecraft, taken on March 1, show Ceres as a crescent, mostly in shadow because the spacecraft’s trajectory put it on a side of Ceres that faces away from the sun until mid-April. When Dawn emerges from Ceres’ dark side, it will deliver ever-sharper images as it spirals to lower orbits around the planet.

“We feel exhilarated,” said Chris Russell, principal investigator of the Dawn mission at the University of California, Los Angeles (UCLA). “We have much to do over the next year and a half, but we are now on station with ample reserves, and a robust plan to obtain our science objectives.”

Dawn’s mission is managed by JPL for NASA’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team.

For a complete list of mission participants, visit:

http://dawn.jpl.nasa.gov/mission

For more information about Dawn, visit:

http://www.nasa.gov/dawn

track.php?msgid=155012&act=2FIS&r=17340975&c=1389932

NASA’s New Horizons Spacecraft Begins First Stages of Pluto Encounter

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PRESS RELEASE (NASA/JPL) – NASA’s New Horizons spacecraft recently began its long-awaited, historic encounter with Pluto. The spacecraft is entering the first of several approach phases that culminate July 14 with the first close-up flyby of the dwarf planet, 4.67 billion miles (7.5 billion kilometers) from Earth.

“NASA first mission to distant Pluto will also be humankind’s first close up view of this cold, unexplored world in our solar system,” said Jim Green, director of NASA’s Planetary Science Division at the agency’s Headquarters in Washington. “The New Horizons team worked very hard to prepare for this first phase, and they did it flawlessly.”


NASA’s New Horizons is the first mission to Pluto and the Kuiper Belt of icy, rocky mini-worlds on the solar system’s outer frontier. This animation follows the New Horizons spacecraft as it leaves Earth after its January 2006 launch, through a gravity-assist flyby of Jupiter in February 2007, to the encounter with Pluto and its moons in summer 2015. (Image Credit: NASA/JHUAPL)

The fastest spacecraft when it was launched, New Horizons lifted off in January 2006. It awoke from its final hibernation period last month after a voyage of more than 3 billion miles, and will soon pass close to Pluto, inside the orbits of its five known moons. In preparation for the close encounter, the mission’s science, engineering and spacecraft operations teams configured the piano-sized probe for distant observations of the Pluto system that start Sunday, Jan. 25 with a long-range photo shoot.

The images captured by New Horizons’ telescopic Long-Range Reconnaissance Imager (LORRI) will give mission scientists a continually improving look at the dynamics of Pluto’s moons. The images also will play a critical role in navigating the spacecraft as it covers the remaining 135 million miles (220 million kilometers) to Pluto.

“We’ve completed the longest journey any spacecraft has flown from Earth to reach its primary target, and we are ready to begin exploring,” said Alan Stern, New Horizons principal investigator from Southwest Research Institute in Boulder, Colorado.

LORRI will take hundreds of pictures of Pluto over the next few

Timeline of the approach and departure phases — surrounding close approach on July 14, 2015 — of the New Horizons Pluto encounter. Image Credit: NASA/JHU APL/SwRI
Timeline of the approach and departure phases — surrounding close approach on July 14, 2015 — of the New Horizons Pluto encounter.
Image Credit: NASA/JHU APL/SwRI

months to refine current estimates of the distance between the spacecraft and the dwarf planet. Though the Pluto system will resemble little more than bright dots in the camera’s view until May, mission navigators will use the data to design course-correction maneuvers to aim the spacecraft toward its target point this summer. The first such maneuver could occur as early as March.

“We need to refine our knowledge of where Pluto will be when New Horizons flies past it,” said Mark Holdridge, New Horizons encounter mission manager at Johns Hopkins University’s Applied Physics Laboratory (APL) in Laurel, Maryland. “The flyby timing also has to be exact, because the computer commands that will orient the spacecraft and point the science instruments are based on precisely knowing the time we pass Pluto – which these images will help us determine.”

The “optical navigation” campaign that begins this month marks the first time pictures from New Horizons will be used to help pinpoint Pluto’s location.

Throughout the first approach phase, which runs until spring, New Horizons will conduct a significant amount of additional science. Spacecraft instruments will gather continuous data on the interplanetary environment where the planetary system orbits, including measurements of the high-energy particles streaming from the sun and dust-particle concentrations in the inner reaches of the Kuiper Belt. In addition to Pluto, this area, the unexplored outer region of the solar system, potentially includes thousands of similar icy, rocky small planets.

More intensive studies of Pluto begin in the spring, when the cameras and spectrometers aboard New Horizons will be able to provide image resolutions higher than the most powerful telescopes on Earth. Eventually, the spacecraft will obtain images good enough to map Pluto and its moons more accurately than achieved by previous planetary reconnaissance missions.

APL manages the New Horizons mission for NASA’s Science Mission Directorate in Washington. Alan Stern, of the Southwest Research Institute (SwRI), headquartered in San Antonio, is the principal investigator and leads the mission. SwRI leads the science team, payload operations, and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. APL designed, built and operates the spacecraft.

For more information about the New Horizons mission, visit:
NASA’s New Horizon’s Webpage

NASA’s Pluto–Kuiper Belt Mission Webpage

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown@nasa.gov

Michael Buckley
Johns Hopkins University Applied Physics Laboratory, Laurel, Md.
240-228-7536
michael.buckley@jhuapl.edu

Maria Stothoff
Southwest Research Institute, San Antonio
210-522-3305
maria.stothoff@swri.org

Components of Beagle 2 Flight System on Mars

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PRESS RELEASE (JPL) – The Beagle 2 Mars Lander, built by the United Kingdom, has been thought lost on Mars since 2003, but has now been found in images from NASA’s Mars Reconnaissance Orbiter.

Beagle 2 was released by the European Space Agency’s Mars Express orbiter but never heard from after its expected landing. Images from the High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter have been interpreted as showing the Beagle 2 did make a soft landing and at least partially deployed its solar panels.

A set of three observations with the orbiter’s High Resolution Imaging Science Experiment (HiRISE) camera shows Beagle 2 partially deployed on the surface of the planet, ending the mystery of what happened to the mission more than a decade ago. They show that the lander survived its Dec. 25, 2003, touchdown enough to at least partially deploy its solar arrays.

“I am delighted that Beagle 2 has finally been found on Mars,” said Mark Sims of the University of Leicester, U.K. He was an integral part of the Beagle 2 project from the start, leading the initial study phase and was Beagle 2 mission manager. “Every Christmas Day since 2003 I have wondered what happened to Beagle 2. My Christmas Day in 2003 alongside many others who worked on Beagle 2 was ruined by the disappointment of not receiving data from the surface of Mars. To be frank I had all but given up hope of ever knowing what happened to Beagle 2. The images show that we came so close to achieving the goal of science on Mars.

HiRISE images initially searched by Michael Croon of Trier, Germany, a former member of the European Space Agency’s Mars Express operations team, provide evidence for the lander and key descent components on the surface of Mars within the expected landing area of Isidis Planitia, an impact basin close to the equator.

Subsequent re-imaging and analysis by the Beagle 2 team, the HiRISE team and NASA’s Jet Propulsion Laboratory, Pasadena, California, have confirmed that the targets discovered are of the correct size, shape, color and dispersion to be Beagle 2. JPL planetary geologist Tim Parker, who has assisted in the search and processed some of the images said, “I’ve been looking over the objects in the images carefully, and I’m convinced that these are Beagle 2 hardware.”

Analysis of the images indicates what appears to be a partially deployed configuration, with what is thought to be the rear cover with its pilot/drogue chute (still attached) and main parachute close by. Due to the small size of Beagle 2 (less than 7 feet, or 2 meters across for the deployed lander) it is right at the limit of detection of HiRISE, the highest-resolution camera orbiting Mars. The targets are within the expected landing area at a distance of about three miles (five kilometers) from its center.

“I can imagine the sense of closure that the Beagle 2 team must feel,” said Richard Zurek of JPL, project scientist now for Mars Reconnaissance Orbiter (MRO) and previously for NASA’s still-missing 1998 Mars Polar Lander. “MRO has helped find safe landing sites on Mars for the Curiosity and Phoenix missions and has searched for missing craft to learn what may have gone wrong. It’s an extremely difficult task, as the craft are small and the search areas are vast. It takes the best camera we have in Mars orbit and work by dedicated individuals to be successful at this.”

HiRISE is operated by the University of Arizona, Tucson. The instrument was built by Ball Aerospace & Technologies Corp. of Boulder, Colorado. The Mars Reconnaissance Orbiter Project is managed for NASA’s Science Mission Directorate in Washington, by JPL, a division of the California Institute of Technology, Pasadena.

View all images (color) on JPL site

For more information about HiRISE

Additional information about MRO

Media Contact

Guy Webster
Jet Propulsion Laboratory, Pasadena, California
818-354-6278
guy.webster@jpl.nasa.gov