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Map of Mars Gravity | NASA



Map of Mars Gravity 






A new map of Mars' gravity made with three NASA spacecraft is the most detailed to date, providing a revealing glimpse into the hidden interior of the Red Planet. The map was derived using Doppler and range tracking data collected by NASA's Deep Space Network from three NASA spacecraft in orbit around Mars: Mars Global Surveyor, Mars Odyssey, and the Mars Reconnaissance Orbiter.

This view of the Martian gravity map shows the Tharsis volcanoes and surrounding flexure. Tharsis is a volcanic plateau on Mars thousands of miles across with the largest volcanoes in the solar system. The white areas in the center are higher-gravity regions produced by the massive Tharsis volcanoes, and the surrounding blue areas are lower-gravity regions that may be cracks in the crust (lithosphere).

Image Credit: MIT/UMBC-CRESST/GSFC

Last Updated: March 21, 2016
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Odyssey, Mars Reconnaissance Orbiter (MRO)



Mars



March 21, 2016




New Gravity Map Gives Best View Yet Inside Mars


A new map of Mars' gravity made with three NASA spacecraft is the most detailed to date, providing a revealing glimpse into the hidden interior of the Red Planet.

"Gravity maps allow us to see inside a planet, just as a doctor uses an X-ray to see inside a patient," said Antonio Genova of the Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts. "The new gravity map will be helpful for future Mars exploration, because better knowledge of the planet's gravity anomalies helps mission controllers insert spacecraft more precisely into orbit about Mars. Furthermore, the improved resolution of our gravity map will help us understand the still-mysterious formation of specific regions of the planet." Genova, who is affiliated with MIT but is located at NASA's Goddard Space Flight Center in Greenbelt, Maryland, is the lead author of a paper on this research published online March 5 in the journal Icarus.



Scientists have used small fluctuations in the orbits of three NASA spacecraft to map the gravity field of Mars.
Credits: NASA/GSFC/Scientific Visualization Studio
High-resolution images and video

The improved resolution of the new gravity map suggests a new explanation for how some features formed across the boundary that divides the relatively smooth northern lowlands from heavily cratered southern highlands. Also, the team confirmed that Mars has a liquid outer core of molten rock by analyzing tides in the Martian crust and mantle caused by the gravitational pull of the sun and the two moons of Mars. Finally, by observing how Mars' gravity changed over 11 years – the period of an entire cycle of solar activity -- the team inferred the massive amount of carbon dioxide that freezes out of the atmosphere onto a Martian polar ice cap when it experiences winter. They also observed how that mass moves between the south pole and the north pole with the change of season in each hemisphere.



A map of Martian gravity looking down on the North Pole (center). White and red are areas of higher gravity; blue indicates areas of lower gravity.
Credits: MIT/UMBC-CRESST/GSFC

The map was derived using Doppler and range tracking data collected by NASA's Deep Space Network from three NASA spacecraft in orbit around Mars: Mars Global Surveyor (MGS), Mars Odyssey (ODY), and the Mars Reconnaissance Orbiter (MRO). Like all planets, Mars is lumpy, which causes the gravitational pull felt by spacecraft in orbit around it to change. For example, the pull will be a bit stronger over a mountain, and slightly weaker over a canyon.

Slight differences in Mars' gravity changed the trajectory of the NASA spacecraft orbiting the planet, which altered the signal being sent from the spacecraft to the Deep Space Network. These small fluctuations in the orbital data were used to build a map of the Martian gravity field.



A map of Martian gravity looking down at the South Pole (center). White and red are areas of higher gravity; blue indicates areas of lower gravity.
Credits: MIT/UMBC-CRESST/GSFC

The gravity field was recovered using about 16 years of data that were continuously collected in orbit around Mars. However, orbital changes from uneven gravity are tiny, and other forces that can perturb the motion of the spacecraft had to be carefully accounted for, such as the force of sunlight on the spacecraft's solar panels and drag from the Red Planet's thin upper atmosphere. It took two years of analysis and computer modeling to remove the motion not caused by gravity.

"With this new map, we've been able to see gravity anomalies as small as about 100 kilometers (about 62 miles) across, and we've determined the crustal thickness of Mars with a resolution of around 120 kilometers (almost 75 miles)," said Genova. "The better resolution of the new map helps interpret how the crust of the planet changed over Mars' history in many regions."

For example, an area of lower gravity between Acidalia Planitia and Tempe Terra was interpreted before as a system of buried channels that delivered water and sediments from Mars' southern highlands into the northern lowlands billions of years ago when the Martian climate was wetter than it is today. The new map reveals that this low gravity anomaly is definitely larger and follows the boundary between the highlands and the lowlands. This system of gravity troughs is unlikely to be only due to buried channels because in places the region is elevated above the surrounding plains. The new gravity map shows that some of these features run perpendicular to the local topography slope, against what would have been the natural downhill flow of water.



A Martian gravity map showing the Tharsis volcanoes and surrounding flexure. The white areas in the center are higher-gravity regions produced by the massive Tharsis volcanoes, and the surrounding blue areas are lower-gravity regions that may be cracks in the crust (lithosphere).
Credits: MIT/UMBC-CRESST/GSFC

An alternative explanation is that this anomaly may be a consequence of a flexure or bending of the lithosphere -- the strong, outermost layer of the planet -- due to the formation of the Tharsis region. Tharsis is a volcanic plateau on Mars thousands of miles across with the largest volcanoes in the solar system. As the Tharsis volcanoes grew, the surrounding lithosphere buckled under their immense weight.

The new gravity field also allowed the team to confirm indications from previous gravity solutions that Mars has a liquid outer core of molten rock. The new gravity solution improved the measurement of the Martian tides, which will be used by geophysicists to improve the model of Mars' interior.

Changes in Martian gravity over time have been previously measured using the MGS and ODY missions to monitor the polar ice caps. For the first time, the team used MRO data to continue monitoring their mass. The team has determined that when one hemisphere experiences winter, approximately 3 trillion to 4 trillion tons of carbon dioxide freezes out of the atmosphere onto the northern and southern polar caps, respectively. This is about 12 to 16 percent of the mass of the entire Martian atmosphere. NASA's Viking missions first observed this massive seasonal precipitation of carbon dioxide. The new observation confirms numerical predictions from the Mars Global Reference Atmospheric Model – 2010.

The research was funded by grants from NASA's Mars Reconnaissance Orbiter mission and NASA's Mars Data Analysis Program.


Bill Steigerwald

NASA Goddard Space Flight Center, Greenbelt, Maryland

William.A.Steigerwald@nasa.gov

Last Updated: March 21, 2016
Editor: Bill Steigerwald


Tags: Goddard Space Flight Center, Mars, Mars Odyssey, Mars Reconnaissance Orbiter (MRO), Solar System



MRO



Feb. 19, 2016




Jarosite in the Noctis Labyrinthus Region of Mars



This image, acquired on Nov. 24, 2015 by the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter, shows the western side of an elongated pit depression in the eastern Noctis Labyrinthus region of Mars. Along the pit's upper wall is a light-toned layered deposit. Noctis Labyrinthus is a huge region of tectonically controlled valleys located at the western end of the Valles Marineris canyon system.

Spectra extracted from the light-toned deposit by the spacecraft's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument are consistent with the mineral jarosite, which is a potassium and iron hydrous sulfate. On Earth, jarosite can form in ore deposits or from alteration near volcanic vents, and indicates an oxidizing and acidic environment. The Opportunity rover discovered jarosite at the Meridiani Planum landing site, and jarosite has been found at several other locations on Mars, indicating that it is a common mineral on the Red Planet.

The jarosite-bearing deposit observed here could indicate acidic aqueous conditions within a volcanic system in Noctis Labyrinthus. Above the light-toned jarosite deposit is a mantle of finely layered darker-toned material. CRISM spectra do not indicate this upper darker-toned mantle is hydrated. The deposit appears to drape over the pre-existing topography, suggesting it represents an airfall deposit from either atmospheric dust or volcanic ash.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL-Caltech/Univ. of Arizona
Caption: Cathy Weitz

Last Updated: Feb. 19, 2016
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



Mars



Jan. 11, 2016




Starburst Spider



Mars' seasonal cap of carbon dioxide ice has eroded many beautiful terrains as it sublimates (goes directly from ice to vapor) every spring. In the region where the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter took this image, we see troughs that form a starburst pattern. In other areas these radial troughs have been refered to as spiders, simply because of their shape. In this region the pattern looks more dendritic as channels branch out numerous times as they get further from the center.

The troughs are believed to be formed by gas flowing beneath the seasonal ice to openings where the gas escapes, carrying along dust from the surface below. The dust falls to the surface of the ice in fan-shaped deposits.

This image, covering an area about 1 kilometer (0.6 mile) across, is a portion of the HiRISE observation catalogued as ESP_011842_0980, taken on Feb. 4, 2009. The observation is centered at 81.8 degrees south latitude, 76.2 degrees east longitude. The image was taken at a local Mars time of 4:56 p.m. and the scene is illuminated from the west with a solar incidence angle of 78 degrees, thus the sun was about 12 degrees above the horizon. At a solar longitude of 203.6 degrees, the season on Mars is northern autumn. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace & Technologies Corp., Boulder, Colo.

Image Credit: NASA/JPL-Caltech/University of Arizona

Last Updated: Jan. 11, 2016
Editor: NASA Administrator


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



MRO



Dec. 28, 2015




Boulders on a Martian Landslide



The striking feature in this image, acquired by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter on March 19, 2014, is a boulder-covered landslide along a canyon wall. Landslides occur when steep slopes fail, sending a mass of soil and rock to flow downhill, leaving behind a scarp at the top of the slope. The mass of material comes to rest when it reaches shallower slopes, forming a lobe of material that ends in a well-defined edge called a toe.

This landslide is relatively fresh, as many individual boulders still stand out above the main deposit. Additionally, while several small impact craters are visible in the landslide lobe, they are smaller in size and fewer in number than those on the surrounding valley floor. The scarp itself also looks fresh compared to the rest of the cliff: it, too, has boulders, and more varied topography than the adjacent dusty terrain.

Just to the north of the landslide scarp is a similarly-shaped scar on the cliffside. However, there is no landslide material on the valley floor below it. The older landslide deposit has either been removed or buried, a further indicator of the relative youth of the bouldery landslide.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

More information and image products

Image Credit: NASA/JPL/University of Arizona
Caption: HiRISE Targeting Specialists

Last Updated: Dec. 28, 2015
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



MRO



Nov. 9, 2015




Layers and Fractures in Ophir Chasma, Mars



Ophir Chasma forms the northern portion of the vast Mars canyon system Valles Marineris, and this image, acquired on Aug. 10, 2015, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, features a small part of its wall and floor.

The wall rock shows many sedimentary layers and the floor is covered with wind-blown ridges, which are intermediate in size between sand ripples and sand dunes. Rocks protruding on the floor could be volcanic intrusions of once-molten magma that pushed aside the surrounding sedimentary layers and “froze” in place.

Images like this can help geologists study the formation mechanisms of large tectonic systems like Valles Marineris. (The word “tectonics” does not mean the same thing as “plate tectonics.” Tectonics simply refers to large stresses and strains in a planet’s crust. Plate tectonics is the main type of tectonics that Earth has; Mars does not have plate tectonics.)

More information and image products

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL/University of Arizona
Caption: Kirby Runyon

Last Updated: Nov. 9, 2015
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



Mars



Oct. 7, 2015




All Along the Fractures



The High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter often takes images of Martian sand dunes to study the mobile soils. These images provide information about erosion and movement of surface material, about wind and weather patterns, even about the soil grains and grain sizes. However, looking past the dunes, these images also reveal the nature of the substrate beneath.

Within the spaces between the dunes, a resistant and highly fractured surface is revealed. The fractured ground is resistant to erosion by the wind, and suggests the material is bedrock that is now shattered by a history of bending stresses or temperature changes, such as cooling, for example.

Alternately, the surface may be a sedimentary layer that was once wet and shrunk and fractured as it dried, like gigantic mud cracks. In either case, the relative small and indistinct fractures have trapped the dark dune sand marching overhead. Now the fractures have become quite distinct, allowing us to examine the orientation and spacing of the fractures to learn more about the processes that formed them.

This view is one image product from HiRISE observation ESP_042223_1890, taken July 30, 2015, at 2:33 p.m. local Mars time, 8.719 degrees north latitude, 67.347 degrees east longitude.

HiRISE is one of six instruments on the Mars Reconnaissance Orbiter. The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and collaborates with JPL to operate it.

Image Credit: NASA/JPL-Caltech/University of Arizona
Caption: Mike Mellon

Last Updated: Oct. 7, 2015
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



Journey to Mars



Sept. 29, 2015




Dark, Recurring Streaks on Walls of Garni Crater on Mars



Dark narrow streaks, called "recurring slope lineae," emanate from the walls of Garni Crater on Mars, in this view constructed from observations by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

The dark streaks here are up to few hundred yards, or meters, long. They are hypothesized to be formed by flow of briny liquid water on Mars.

The image was produced by first creating a 3-D computer model (a digital terrain map) of the area based on stereo information from two HiRISE observations, and then draping an image over the land-shape model. The vertical dimension is exaggerated by a factor of 1.5 compared to horizontal dimensions. The draped image is a red waveband (monochrome) product from HiRISE observation ESP_031059_1685, taken on March 12, 2013 at 11.5 degrees south latitude, 290.3 degrees east longitude. Other image products from this observation are at http://hirise.lpl.arizona.edu/ESP_031059_1685.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL-Caltech/Univ. of Arizona

Last Updated: Sept. 29, 2015
Editor: Tony Greicius


Tags: Image of the Day, Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO)



Journey to Mars



Aug. 20, 2015




Curiosity Low-Angle Self-Portrait at 'Buckskin' Drilling Site on Mount Sharp



This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle above the "Buckskin" rock target, where the mission collected its seventh drilled sample. The site is in the "Marias Pass" area of lower Mount Sharp.

The scene combines dozens of images taken by Curiosity's Mars Hand Lens Imager (MAHLI) on Aug. 5, 2015, during the 1,065th Martian day, or sol, of the rover's work on Mars. The 92 component images are among MAHLI Sol 1065 raw images at http://mars.nasa.gov/msl/multimedia/raw/?s=1065&camera=MAHLI. For scale, the rover's wheels are 20 inches (50 centimeters) in diameter and about 16 inches (40 centimeters) wide.

Curiosity drilled the hole at Buckskin during Sol 1060 (July 30, 2015). Two patches of pale, powdered rock material pulled from Buckskin are visible in this scene, in front of the rover. The patch closer to the rover is where the sample-handling mechanism on Curiosity's robotic arm dumped collected material that did not pass through a sieve in the mechanism. Sieved sample material was delivered to laboratory instruments inside the rover. The patch farther in front of the rover, roughly triangular in shape, shows where fresh tailings spread downhill from the drilling process. The drilled hole, 0.63 inch (1.6 centimeters) in diameter, is at the upper point of the tailings.

The rover is facing northeast, looking out over the plains from the crest of a 20-foot (6-meter) hill that it climbed to reach the Marias Pass area. The upper levels of Mount Sharp are visible behind the rover, while Gale Crater’s northern rim dominates the horizon on the left and right of the mosaic.

A portion of this selfie cropped tighter around the rover is at http://photojournal.jpl.nasa.gov/catalog/PIA19808. Another version of the wide view, presented in a projection that shows the horizon as a circle, is at http://photojournal.jpl.nasa.gov/catalog/PIA19806.

MAHLI is mounted at the end of the rover's robotic arm. For this self-portrait, the rover team positioned the camera lower in relation to the rover body than for any previous full self-portrait of Curiosity. This yielded a view that includes the rover's "belly," as in a partial self-portrait (http://photojournal.jpl.nasa.gov/catalog/PIA16137) taken about five weeks after Curiosity's August 2012 landing inside Mars' Gale Crater. Before sending Curiosity the arm-positioning commands for this Buckskin belly panorama, the team previewed the low-angle sequence of camera pointings on a test rover in California. A mosaic from that test is at http://photojournal.jpl.nasa.gov/catalog/PIA19810.

This selfie at Buckskin does not include the rover's robotic arm beyond a portion of the upper arm held nearly vertical from the shoulder joint. Shadows from the rest of the arm and the turret of tools at the end of the arm are visible on the ground. With the wrist motions and turret rotations used in pointing the camera for the component images, the arm was positioned out of the shot in the frames or portions of frames used in this mosaic. This process was used previously in acquiring and assembling Curiosity self-portraits taken at sample-collection sites "Rocknest" (http://photojournal.jpl.nasa.gov/catalog/PIA16468), "John Klein" (http://photojournal.jpl.nasa.gov/catalog/PIA16937), "Windjana" (http://photojournal.jpl.nasa.gov/catalog/PIA18390) and "Mojave" (http://photojournal.jpl.nasa.gov/catalog/PIA19142).

MAHLI was built by Malin Space Science Systems, San Diego. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.

More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/.

Credit: NASA/JPL-Caltech/MSSS

Last Updated: Aug. 20, 2015
Editor: Tony Greicius


Tags: Image of the Day, Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Science Laboratory (Curiosity), Solar System



MRO



Aug. 12, 2015




For Anniversary of Orbiter's Launch: Seasonal Flows in Mars' Valles Marineris



Among the many discoveries by NASA's Mars Reconnaissance Orbiter since the mission was launched on Aug. 12, 2005, are seasonal flows on some steep slopes. These flows have a set of characteristics consistent with shallow seeps of salty water.

This July 21, 2015, image from the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera shows examples of these flows on a slope within Coprates Chasma, which is part of the grandest canyon system on Mars, Valles Marineris. The image covers an area of ground one-third of a mile (536 meters) wide.

These flows are called recurring slope lineae because they fade and disappear during cold seasons and reappear in warm seasons, repeating this pattern every Martian year. The flows seen in this image are on a north-facing slope, so they are active in northern-hemisphere spring. The flows emanate from the relatively bright bedrock and flow onto sandy fans, where they are remarkably straight, following linear channels. Valles Marineris contains more of these flows than everywhere else on Mars combined. At any season, some are active, though on different slope aspects at different seasons.

Future human explorers (and settlers?) will need water to drink, grow food, produce oxygen to breath, and make rocket fuel. Bringing all of that water from Earth would be extremely expensive, so using water on Mars is essential. Although there is plenty of water ice at high latitudes, surviving the cold winters would be difficult. An equatorial source of water would be preferable, so Valles Marineris may be the best destination. However, the chemistry of this water must be understood before betting any lives on it.

For more information about recurring slope lineae, see http://www.jpl.nasa.gov/news/news.php?feature=3981 and http://www.uahirise.org/sim/2013-12-10/ .

The location of the site in this image is 12.9 degrees south latitude, 295.4 degrees east latitude. The image is an excerpt from HiRISE observation ESP_042228_1670. Other image products from this observation are available at http://hirise.lpl.arizona.edu/ESP_042228_1670 .

HiRISE is one of six instruments on the Mars Reconnaissance Orbiter. The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and collaborates with JPL to operate it.

Image credit: NASA/JPL-Caltech/Univ. of Arizona

Last Updated: Aug. 12, 2015
Editor: Tony Greicius


Tags: Image of the Day, Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



MRO



July 30, 2015




Frosty Gullies on the Northern Plains of Mars



Seasonal frost commonly forms at middle and high latitudes on Mars, much like winter snow on Earth. However, on Mars most frost is carbon dioxide (dry ice) rather than water ice. This frost appears to cause surface activity, including flows in gullies.

This image, acquired on April 11, 2015, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter, shows frost in gully alcoves in a crater on the Northern plains. The frost highlights details of the alcoves, since it forms in different amounts depending on slopes and shadows as well as the type of material making up the ground. Rugged rock outcrops appear dark and shadowed, while frost highlights the upper alcove and the steepest route down the slope.

Most changes associated with gullies are observed in the Southern hemisphere. However, some are seen in the Northern hemisphere, where steep slopes are less common. HiRISE is monitoring these gullies to look for changes and to understand the behavior of the frost.

More information and image products

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL/University of Arizona
Caption: Colin Dundas

Last Updated: July 30, 2015
Editor: Sarah Loff


Tags: Image of the Day, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO)



Mars Curiosity



July 2, 2015




Curiosity's Stars and Stripes



This view of the American flag medallion on NASA's Mars rover Curiosity was taken by the rover's Mars Hand Lens Imager (MAHLI) during the 44th Martian day, or sol, of Curiosity's work on Mars (Sept. 19, 2012). The flag is one of four "mobility logos" placed on the rover's mobility rocker arms.

› View Presidential Plaque

The circular medallion of the flag is made of anodized aluminum and measures 2.68 inches (68 millimeters) in diameter. The medallion was affixed with bolts to locations on the rocker arms where flight hardware was once considered, but ultimately deemed unnecessary.

The other three medallions adorning the rover's rocker arms are the NASA logo, the JPL logo and the Curiosity mission logo.

The main purpose of Curiosity's MAHLI camera is to acquire close-up, high-resolution views of rocks and soil at the rover's Gale Crater field site. The camera is capable of focusing on any target at distances of about 0.8 inch (2.1 centimeters) to infinity, providing versatility for other uses, such as views of the rover itself from different angles.

Image Credit: NASA/JPL-Caltech/MSSS

Last Updated: July 30, 2015
Editor: NASA Administrator


Tags: Image of the Day, Mars, Mars Science Laboratory (Curiosity), Solar System



MRO



July 1, 2015




Light Toned Deposit in the Aureum Chaos Region on Mars



The High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter acquired this closeup image of a light-toned deposit in Aureum Chaos, a 368 kilometer (229 mile) wide area in the eastern part of Valles Marineris, on Jan. 15, 2015, at 2:51 p.m. local Mars time.

The objective of this observation is to examine a light-toned deposit in a region of what is called “chaotic terrain.” There are indications of layers in the image. Some shapes suggest erosion by a fluid moving north and south. The top of the light-toned deposit appears rough, in contrast to the smoothness of its surroundings.

More information and image products

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL/University of Arizona
Caption: HIRISE Science Team

Last Updated: July 30, 2015
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



MRO



June 5, 2015




Fresh Crater Near Sirenum Fossae Region of Mars



The High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA's Mars Reconnaissance Orbiter acquired this closeup image of a "fresh" (on a geological scale, though quite old on a human scale) impact crater in the Sirenum Fossae region of Mars on March 30, 2015.

This impact crater appears relatively recent as it has a sharp rim and well-preserved ejecta. The steep inner slopes are carved by gullies and include possible recurring slope lineae on the equator-facing slopes. Fresh craters often have steep, active slopes, so the HiRISE team is monitoring this crater for changes over time. The bedrock lithology is also diverse. The crater is a little more than 1-kilometer wide.

More information and image products

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter Project and Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington.

Image Credit: NASA/JPL/University of Arizona
Caption: Alfred McEwen

Last Updated: July 30, 2015
Editor: Sarah Loff


Tags: Image of the Day, Mars, Mars Reconnaissance Orbiter (MRO), Solar System



Journey to Mars



May 28, 2015




Parachute Testing for NASA's InSight Mission



This parachute testing for NASA's InSight mission to Mars was conducted inside the world's largest wind tunnel, at NASA Ames Research Center, Moffett Field, California, in February 2015.

The wind tunnel is 80 feet (24 meters) tall and 120 feet (37 meters) wide. It is part of the National Full-Scale Aerodynamics Complex, operated by the Arnold Engineering Development Center of the U.S. Air Force.

InSight, for Interior Exploration Using Seismic Investigations, Geodesy and Heat Transport, is scheduled to launch in March 2016 and land on Mars in September 2016. The lander will investigate the deep interior of Mars to gain information about how rocky planets, including Earth, formed and evolved.

Lockheed Martin Space Systems, Denver, is building the InSight spacecraft. The InSight Project is managed by NASA's Jet Propulsion Laboratory, Pasadena, California, for the NASA Science Mission Directorate, Washington. InSight is part of NASA's Discovery Program, which is managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

Image Credit: NASA/JPL-Caltech/Lockheed Martin

Last Updated: July 30, 2015
Editor: Tony Greicius


Tags: Ames Research Center, Image of the Day, InSight Mars Lander, Journey to Mars, Mars



Solar System and Beyond



May 4, 2015




Traffic Around Mars Gets Busy




This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet's two natural satellites.
Credits: NASA/JPL-Caltech
Full image and caption

NASA has beefed up a process of traffic monitoring, communication and maneuver planning to ensure that Mars orbiters do not approach each other too closely.

Last year's addition of two new spacecraft orbiting Mars brought the census of active Mars orbiters to five, the most ever. NASA's Mars Atmosphere and Volatile Evolution (MAVEN) and India's Mars Orbiter Mission joined the 2003 Mars Express from ESA (the European Space Agency) and two from NASA: the 2001 Mars Odyssey and the 2006 Mars Reconnaissance Orbiter (MRO). The newly enhanced collision-avoidance process also tracks the approximate location of NASA's Mars Global Surveyor, a 1997 orbiter that is no longer working.

It's not just the total number that matters, but also the types of orbits missions use for achieving their science goals. MAVEN, which reached Mars on Sept. 21, 2014, studies the upper atmosphere. It flies an elongated orbit, sometimes farther from Mars than NASA's other orbiters and sometimes closer to Mars, so it crosses altitudes occupied by those orbiters. For safety, NASA also monitors positions of ESA's and India's orbiters, which both fly elongated orbits.

"Previously, collision avoidance was coordinated between the Odyssey and MRO navigation teams," said Robert Shotwell, Mars Program chief engineer at NASA's Jet Propulsion Laboratory, Pasadena, California. "There was less of a possibility of an issue. MAVEN's highly elliptical orbit, crossing the altitudes of other orbits, changes the probability that someone will need to do a collision-avoidance maneuver. We track all the orbiters much more closely now. There's still a low probability of needing a maneuver, but it's something we need to manage."

Traffic management at Mars is much less complex than in Earth orbit, where more than 1,000 active orbiters plus additional pieces of inactive hardware add to hazards. As Mars exploration intensifies, though, and will continue to do so with future missions, precautions are increasing. The new process was established to manage this growth as new members are added to the Mars orbital community in years to come.

All five active Mars orbiters use the communication and tracking services of NASA's Deep Space Network, which is managed at JPL. This brings trajectory information together, and engineers can run computer projections of future trajectories out to a few weeks ahead for comparisons.

"It's a monitoring function to anticipate when traffic will get heavy," said Joseph Guinn, manager of JPL's Mission Design and Navigation Section. "When two spacecraft are predicted to come too close to one another, we give people a heads-up in advance so the project teams can start coordinating about whether any maneuvers are needed."

The amount of uncertainty in the predicted location of a Mars orbiter a few days ahead is more than a mile (more than two kilometers). Calculating projections for weeks ahead multiplies the uncertainty to dozens of miles, or kilometers. In most cases when a collision cannot be ruled out from projections two weeks ahead, improved precision in the forecasting as the date gets closer will rule out a collision with no need for avoidance action. Mission teams for the relevant orbiters are notified in advance when projections indicate a collision is possible, even if the possibility will likely disappear in subsequent projections. This situation occurred on New Year's weekend, 2015.

On Jan. 3, automated monitoring determined that two weeks later, MAVEN and MRO could come within about two miles (three kilometers) of each other, with large uncertainties remaining in the exact passing distance. Although that was a Saturday, automatic messages went out to the teams operating the orbiters.

"In this case, before the timeline got short enough to need to plan an avoidance maneuver, the uncertainties shrank, and that ruled out the chance of the two spacecraft coming too near each other," Guinn said. This is expected to be the usual pattern, with the advance warning kicking off higher-level monitoring and initial discussions about options.

If preparations for an avoidance maneuver were called for, spacecraft commands would be written, tested and approved for readiness, but such commands would not be sent to a spacecraft unless projections a day or two ahead showed probability of a hazardous conjunction. The amount of uncertainty about each spacecraft's exact location varies, so the proximity considered unsafe also varies. For some situations, a day-ahead projection of two craft coming within about 100 yards (100 meters) of each other could trigger a maneuver.

The new formal collision-avoidance process for Mars is part of NASA's Multi-Mission Automated Deep-Space Conjunction Assessment Process. A side benefit of it is that information about when two orbiters will be near each other -- though safely apart -- could be used for planning coordinated science observations. The pair could look at some part of Mars or its atmosphere from essentially the same point of view simultaneously with complementary instruments.

Odyssey, MRO and MAVEN -- together with NASA's two active Mars rovers, Opportunity and Curiosity -- are part of NASA's robotic exploration of Mars that is preparing the way for human-crewed missions there in the 2030s and later, in NASA's Journey to Mars strategy.

NASA's Goddard Space Flight Center manages the MAVEN project for the NASA Science Mission Directorate, Washington. MAVEN's principal investigator is based at the University of Colorado's Laboratory for Atmospheric and Space Physics. JPL, a division of the California Institute of Technology in Pasadena, manages NASA's Mars Exploration Program and the Odyssey and MRO projects for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built all three NASA Mars orbiters.

For more about NASA's Mars Exploration Program, visit:

http://mars.jpl.nasa.gov

http://www.nasa.gov/mars


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

2015-150

Last Updated: July 30, 2015
Editor: Tony Greicius


Tags: Mars, Mars Odyssey, Mars Reconnaissance Orbiter (MRO), MAVEN (Mars Atmosphere and Volatile Evolution), Solar System



MRO



April 16, 2014




NASA Mars Orbiter Spies Rover Near Martian Butte




NASA's Curiosity Mars rover and tracks from its driving are visible in this view from orbit, acquired on April 11, 2014, by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.
Credits: NASA/JPL-Caltech/Univ. of Arizona
Full image and caption



NASA's Curiosity Mars rover used its Navigation Camera (Navcam) on April 11, 2014, to record this scene of a butte called "Mount Remarkable" and surrounding outcrops at a waypoint called "the Kimberley" inside Gale Crater.
Credits: NASA/JPL-Caltech
Full image and caption



NASA's Curiosity Mars rover and its tracks are visible in this view combining information from three observations by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. The image appears three-dimensional when viewed through red-blue glasses.
Credits: NASA/JPL-Caltech/Univ. of Arizona
Full image and caption

Scientists using NASA's Curiosity Mars rover are eyeing a rock layer surrounding the base of a small butte, called "Mount Remarkable," as a target for investigating with tools on the rover's robotic arm.

The rover works near this butte in an image taken on April 11 by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. It is available at: http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA18081

A rover's-eye view of Mount Remarkable and surroundings as seen from Curiosity's position in that HiRISE image is available in a mosaic of images from Curiosity's Navigation Camera (Navcam), at: http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA18083

The butte stands about 16 feet (5 meters) high. Curiosity's science team refers to the rock layer surrounding the base of Mount Remarkable as the "middle unit" because its location is intermediate between rocks that form buttes in the area and lower-lying rocks that show a pattern of striations.

Depending on what the mission scientists learn from a close-up look at the rock and identification of chemical elements in it, a site on this middle unit may become the third rock that Curiosity samples with its drill. The rover carries laboratory instruments to analyze rock powder collected by the drill. The mission's first two drilled samples, in an area called Yellowknife Bay near Curiosity's landing site, yielded evidence last year for an ancient lakebed environment with available energy and ingredients favorable for microbial life.

The rover's current location, where multiple types of rocks are exposed close together, is called "the Kimberley." Here and, later, at outcrops on the slope of Mount Sharp inside Gale Crater, researchers plan to use Curiosity's science instruments to learn more about habitable past conditions and environmental changes.

NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. The project designed and built Curiosity and operates the rover on Mars.

For more information about Curiosity, visit http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/. You can follow the mission on Facebook at http://www.facebook.com/marscuriosity and on Twitter at http://www.twitter.com/marscuriosity.


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

2014-116

Last Updated: July 30, 2015
Editor: Tony Greicius


Tags: Mars, Mars Reconnaissance Orbiter (MRO), Mars Science Laboratory (Curiosity), Science Instruments, Solar System



Mars Odyssey



Feb. 10, 2014




NASA Mars Orbiters See Clues to Possible Water Flows




This image combines a photograph of seasonal dark flows on a Martian slope with a grid of colors based on data collected by a mineral-mapping spectrometer observing the same area.
NASA/JPL-Caltech/UA/JHU-APL
Full image and caption



Dark, seasonal flows emanate from bedrock exposures at Palikir Crater on Mars in this image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.
Credits: NASA/JPL-Caltech/Univ. of Arizona
Full image and caption

NASA spacecraft orbiting Mars have returned clues for understanding seasonal features that are the strongest indication of possible liquid water that may exist today on the Red Planet.

The features are dark, finger-like markings that advance down some Martian slopes when temperatures rise. The new clues include corresponding seasonal changes in iron minerals on the same slopes and a survey of ground temperatures and other traits at active sites. These support a suggestion that brines with an iron-mineral antifreeze, such as ferric sulfate, may flow seasonally, though there are still other possible explanations.

Researchers call these dark flows "recurring slope lineae." As a result, RSL has become one of the hottest acronyms at meetings of Mars scientists.

"We still don't have a smoking gun for existence of water in RSL, although we're not sure how this process would take place without water," said Lujendra Ojha, a graduate student at the Georgia Institute of Technology, Atlanta, and lead author of two new reports about these flows. He originally discovered them while an undergraduate at the University of Arizona, Tucson, three years ago, in images from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

Ojha and Georgia Tech assistant professor James Wray more recently looked at 13 confirmed RSL sites using images from the same orbiter's Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument. They searched for minerals that RSL might leave in their wake as a way of understanding the nature of these features: water-related or not?

They didn't find any spectral signature tied to water or salts. But they did find distinct and consistent spectral signatures of ferric and ferrous minerals at most of the sites. These iron-bearing minerals were more abundant or featured distinct grain sizes in RSL-related materials as compared to non-RSL slopes. These results are in a paper published in the journal Geophysical Research Letters.

Ojha said, "Just like the RSL themselves, the strength of the spectral signatures varies according to the seasons. They're stronger when it's warmer and less significant when it's colder."

One possible explanation for these changes is a sorting of grain sizes, such as removal of fine dust from the surface, which could result from either a wet process or dry one. Two other possible explanations are an increase in the more-oxidized (ferric) component of the minerals, or an overall darkening due to moisture. Either of these would point to water, even though no water was directly detected. The spectral observations might miss the presence of water, because the dark flows are much narrower than the area of ground sampled with each CRISM reading. Also, the orbital observations have been made only in afternoons and could miss morning moisture.

The leading hypothesis for these features is the flow of near-surface water, kept liquid by salts depressing the freezing point of pure water. "The flow of water, even briny water, anywhere on Mars today would be a major discovery, impacting our understanding of present climate change on Mars and possibly indicating potential habitats for life near the surface on modern Mars," said Mars Reconnaissance Orbiter Project Scientist Richard Zurek, of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

In related research, reported in a paper to be published by the journal Icarus next month, the Georgia Tech scientists and colleagues at the University of Arizona; U.S. Geological Survey, Flagstaff, Ariz.; and Polish Academy of Sciences, Warsaw, used the Mars Reconnaissance Orbiter and NASA's Mars Odyssey orbiter to look for patterns in where and when the dark seasonal flows exist on Mars. Their results indicate that many sites with slopes, latitudes and temperatures matching known RSL sites do not have any evident RSL.

They hunted for areas that were ideal locations for RSL formation: areas near the southern mid-latitudes on rocky cliffs. They found 200, but barely any of them had RSL. "Only 13 of the 200 locations had confirmed RSL," said Ojha. "The fact that RSL occur in a few sites and not others indicates additional unknown factors such as availability of water or salts may play a crucial role in RSL formation."

They compared new observations with images from previous years, revealing that RSL are much more abundant some years than others.

"NASA likes to 'follow the water' in exploring the Red Planet, so we'd like to know in advance when and where it will appear," Wray said. "RSL have rekindled our hope of accessing modern water, but forecasting wet conditions remains a challenge."

JPL, a division of the California Institute of Technology, manages the Mars Reconnaissance Orbiter and Mars Odyssey projects for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems in Denver built both orbiters. The University of Arizona operates the HiRISE camera, which was built by Ball Aerospace & Technologies Corp. of Boulder, Colo. The Johns Hopkins University Applied Physics Laboratory, Laurel, Md., provided and operates CRISM.

For more about NASA's Mars exploration missions, see http://www.nasa.gov/mars and http://mars.jpl.nasa.gov . The new research reports about recurring slope lineae are available at http://wray.eas.gatech.edu/Ojha_etal2013-acceptedGRL.pdf and http://wray.eas.gatech.edu/Ojha_etal2014-acceptedIcarus.pdf .

Last Updated: July 30, 2015
Editor: Tony Greicius


Tags: Mars, Mars Odyssey, Mars Reconnaissance Orbiter (MRO), Science Instruments, Solar System, Technology



Mars Odyssey



Oct. 22, 2013




Mars Crater May Actually Be Ancient Supervolcano


Scientists from NASA and the Planetary Science Institute in Tucson, Ariz., have identified what could be a supervolcano on Mars—the first discovery of its kind.

The volcano in question, a vast circular basin on the face of the Red Planet, previously had been classified as an impact crater. Researchers now suggest the basin is actually what remains of an ancient supervolcano eruption. Their assessment is based on images and topographic data from NASA's Mars Odyssey, Mars Global Surveyor and Mars Reconnaissance Orbiter spacecraft, as well as the European Space Agency's Mars Express orbiter.





New research suggests a volcano, not a large impact, may have formed Mars' Eden Patera basin. Left: Reds, yellows show higher elevations in the basin and surrounding area; blues, grays show lower elevations. Right: The dark color indicates younger material draped across the Eden Patera depression.
Credits: NASA/JPL/Goddard (left) and ESA (right)



In the Oct. 3 issue of the journal Nature, Joseph Michalski, a researcher affiliated with the Planetary Science Institute and the Natural History Museum in London, and Jacob Bleacher of NASA's Goddard Space Flight Center in Greenbelt, Md., laid out their case that the basin, recently named Eden Patera, is a volcanic caldera. Because a caldera is a depression, it can look like a crater formed by an impact, rather than a volcano.

"On Mars, young volcanoes have a very distinctive appearance that allows us to identify them," said Michalski. "The long-standing question has been what ancient volcanoes on Mars look like. Perhaps they look like this one."

The researchers also suggest a large body of magma loaded with dissolved gas (similar to the carbonation in soda) rose through thin crust to the surface quickly. Like a bottle of soda that has been shaken, this supervolcano would have blown its contents far and wide if the top came off suddenly.

"This highly explosive type of eruption is a game-changer, spewing many times more ash and other material than typical, younger Martian volcanoes," said Bleacher. "During these types of eruptions on Earth, the debris may spread so far through the atmosphere and remain so long that it alters the global temperature for years."

After the material is expelled from the eruption, the depression that is left can collapse even further, causing the ground around it to sink. Eruptions like these happened in ages past at what is now Yellowstone National Park in the western United States, Lake Toba in Indonesia and Lake Taupo in New Zealand.

Volcanoes previously had not been identified in the Arabia Terra region of Mars, where Eden Patera is located. The battered, heavily eroded terrain is known for its impact craters. But as Michalski examined this particular basin more closely, he noticed it lacked the typical raised rim of an impact crater.He also could not find a nearby blanket of ejecta, the melted rock that splashes outside the crater when an object hits.

The absence of such key features caused Michalski to suspect volcanic activity. He contacted Bleacher, a volcano specialist, who identified features at Eden Patera that usually indicate volcanism, such as a series of rock ledges that looked like the "bathtub rings" left after a lava lake slowly drains. In addition, the outside of the basin is ringed by the kinds of faults and valleys that occur when the ground collapses because of activity below the surface. The existence of these and other volcanic features in one place convinced the scientists Eden Patera should be reclassified.

The team found a few more candidates for reclassification nearby, suggesting conditions in Arabia Terra may have been favorable for supervolcanoes. It is also possible massive eruptions here could have been responsible for volcanic deposits elsewhere on Mars that have never been linked to a known volcano.

"If just a handful of volcanoes like these were once active, they could have had a major impact on the evolution of Mars," Bleacher said.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the projects operating Mars Odyssey and Mars Reconnaissance Orbiter for NASA's Science Mission Directorate in Washington.

For information about NASA's Mars Odyssey mission, visit:

http://mars.jpl.nasa.gov/odyssey

For information about NASA's Mars Reconnaissance Orbiter, visit:

http://mars.jpl.nasa.gov/mro


Elizabeth Zubritsky
NASA's Goddard Space Flight Center, Greenbelt, Md.

Last Updated: July 30, 2015
Editor: Rob Garner


Tags: Goddard Space Flight Center, Mars, Mars Odyssey, Mars Reconnaissance Orbiter (MRO), Solar System


MRO



Feb. 16, 2011




Blue on Mars

This image shows part of the floor of Rabe Crater, a large impact crater in Mars' southern highlands.

Dark dunes-accumulations of wind blown sand-cover part of crater's floor, and contrast with the surrounding bright-colored outcrops. The extreme close-up view reveals a thumbprint-like texture of smaller ridges and troughs covering the surfaces of the larger dunes. These smaller ripples are also formed and shaped by blowing wind in the thin atmosphere of Mars.

One puzzling question is why the dunes are dark compared with the relative bright layered material contained within the crater. The probable answer is that the source of the dark sand is not local to this crater; rather, this topographic depression has acted as a sand trap.

This image was originally released Oct. 24, 2007.

Image Credit: NASA/JPL-Caltech/University of Arizona

Last Updated: July 31, 2015
Editor: NASA Administrator
Tags: Mars, Mars Reconnaissance Orbiter (MRO), Solar System



http://www.nasa.gov/sites/default/files/thumbnails/image/mars_grav_tharsis.jpg
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