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09/28/2015 10:23 AM EDT

 

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New findings from NASA's Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.

 

MRO

Sept. 28, 2015

15-195

NASA Confirms Evidence That Liquid Water Flows on Today’s Mars

These dark, narrow, 100 meter-long streaks called recurring slope lineae flowing downhill on Mars are inferred to have been formed by contemporary flowing water. Recently, planetary scientists detected hydrated salts on these slopes at Hale crater, corroborating their original hypothesis that the streaks are indeed formed by liquid water. The blue color seen upslope of the dark streaks are thought not to be related to their formation, but instead are from the presence of the mineral pyroxene. The image is produced by draping an orthorectified (Infrared-Red-Blue/Green(IRB)) false color image (ESP_030570_1440) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5.

Credits: NASA/JPL/University of Arizona

Full image and caption

New findings from NASA's Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present-day Mars.

Using an imaging spectrometer on MRO, researchers detected signatures of hydrated minerals on slopes where mysterious streaks are seen on the Red Planet. These darkish 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. They appear in several locations on Mars when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.

“Our quest on Mars has been to ‘follow the water,’ in our search for life in the universe, and now we have convincing science that validates what we’ve long suspected,” said John Grunsfeld, astronaut and associate administrator of NASA’s Science Mission Directorate in Washington. “This is a significant development, as it appears to confirm that water -- albeit briny -- is flowing today on the surface of Mars.”

These downhill flows, known as recurring slope lineae (RSL), often have been described as possibly related to liquid water. The new findings of hydrated salts on the slopes point to what that relationship may be to these dark features. The hydrated salts would lower the freezing point of a liquid brine, just as salt on roads here on Earth causes ice and snow to melt more rapidly. Scientists say it’s likely a shallow subsurface flow, with enough water wicking to the surface to explain the darkening.

Dark narrow streaks called recurring slope lineae emanating out of the walls of Garni crater on Mars. The dark streaks here are up to few hundred meters in length. They are hypothesized to be formed by flow of briny liquid water on Mars. The image is produced by draping an orthorectified (RED) image (ESP_031059_1685) on a Digital Terrain Model (DTM) of the same site produced by High Resolution Imaging Science Experiment (University of Arizona). Vertical exaggeration is 1.5.

Credits: NASA/JPL/University of Arizona

Full image and caption

"We found the hydrated salts only when the seasonal features were widest, which suggests that either the dark streaks themselves or a process that forms them is the source of the hydration. In either case, the detection of hydrated salts on these slopes means that water plays a vital role in the formation of these streaks," said Lujendra Ojha of the Georgia Institute of Technology (Georgia Tech) in Atlanta, lead author of a report on these findings published Sept. 28 by Nature Geoscience.

Ojha first noticed these puzzling features as a University of Arizona undergraduate student in 2010, using images from the MRO's High Resolution Imaging Science Experiment (HiRISE). HiRISE observations now have documented RSL at dozens of sites on Mars. The new study pairs HiRISE observations with mineral mapping by MRO’s Compact Reconnaissance Imaging Spectrometer for Mars (CRISM).

The spectrometer observations show signatures of hydrated salts at multiple RSL locations, but only when the dark features were relatively wide. When the researchers looked at the same locations and RSL weren't as extensive, they detected no hydrated salt.  

Ojha and his co-authors interpret the spectral signatures as caused by hydrated minerals called perchlorates. The hydrated salts most consistent with the chemical signatures are likely a mixture of magnesium perchlorate, magnesium chlorate and sodium perchlorate. Some perchlorates have been shown to keep liquids from freezing even when conditions are as cold as minus 94 degrees Fahrenheit (minus 70 Celsius). on Earth, naturally produced perchlorates are concentrated in deserts, and some types of perchlorates can be used as rocket propellant.

Perchlorates have previously been seen on Mars. NASA's Phoenix lander and Curiosity rover both found them in the planet's soil, and some scientists believe that the Viking missions in the 1970s measured signatures of these salts. However, this study of RSL detected perchlorates, now in hydrated form, in different areas than those explored by the landers. This also is the first time perchlorates have been identified from orbit.

MRO has been examining Mars since 2006 with its six science instruments.

"The ability of MRO to observe for multiple Mars years with a payload able to see the fine detail of these features has enabled findings such as these: first identifying the puzzling seasonal streaks and now making a big step towards explaining what they are," said Rich Zurek, MRO project scientist at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

For Ojha, the new findings are more proof that the mysterious lines he first saw darkening Martian slopes five years ago are, indeed, present-day water.

"When most people talk about water on Mars, they're usually talking about ancient water or frozen water," he said. "Now we know there’s more to the story. This is the first spectral detection that unambiguously supports our liquid water-formation hypotheses for RSL."

The discovery is the latest of many breakthroughs by NASA’s Mars missions.

“It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet,” said Michael Meyer, lead scientist for NASA’s Mars Exploration Program at the agency’s headquarters in Washington. “It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future.” 

This animation simulates a fly-around look at one of the places on Mars where dark streaks advance down slopes during warm seasons, possibly involving liquid water. This site is within Hale Crater. The streaks are roughly the length of a football field.

There are eight co-authors of the Nature Geoscience paper, including Mary Beth Wilhelm at NASA’s Ames Research Center in Moffett Field, California and Georgia Tech; CRISM Principal Investigator Scott Murchie of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland; and HiRISE Principal Investigator Alfred McEwen of the University of Arizona Lunar and Planetary Laboratory in Tucson, Arizona. Others are at Georgia Tech, the Southwest Research Institute in Boulder, Colorado, and Laboratoire de Planétologie et Géodynamique in Nantes, France.

The agency’s Jet Propulsion Laboratory (JPL) in Pasadena, California manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington. Lockheed Martin built the orbiter and collaborates with JPL to operate it.

More information about NASA's journey to Mars is available online at:

https://www.nasa.gov/topics/journeytomars

For more information about the Mars Reconnaissance Orbiter, visit:

http://www.nasa.gov/mro

-end-

Dwayne Brown / Laurie Cantillo
Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

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

Last Updated: Sept. 29, 2015

Editor: Gina Anderson

Tags:  Ames Research Center, Jet Propulsion Laboratory, Journey to Mars, Mars Reconnaissance Orbiter (MRO),

Journey to Mars

Sept. 29, 2015

Recurring "Lineae" on Slopes at Horowitz Crater

The dark, narrow streaks flowing downhill on Mars at sites such as this portion of Horowitz Crater are inferred to be formed by seasonal flow of water on modern-day Mars. The streaks are roughly the length of a football field.

The imaging and topographical information in this processed view come from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

These dark features on the slopes are called "recurring slope lineae" or RSL. Planetary scientists using observations with the Compact Reconnaissance Imaging Spectrometer on the same orbiter detected hydrated salts on these slopes at Horowitz Crater, corroborating the hypothesis that the streaks are formed by briny liquid water.

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 PSP_005787_1475, taken on Oct. 21, 2007, at 32 degrees south latitude, 141 degrees east longitude. Other image products from this observation are at http://www.uahirise.org/PSP_005787_1475.

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:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO),

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Journey to Mars

Sept. 29, 2015

Dark, Recurring Streaks on Walls of Garni Crater

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:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO),

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MRO

Sept. 29, 2015

Recurring 'Lineae' on Slopes at Hale Crater, Mars

Dark, narrow streaks on Martian slopes such as these at Hale Crater are inferred to be formed by seasonal flow of water on contemporary Mars. The streaks are roughly the length of a football field.

The imaging and topographical information in this processed, false-color view come from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.

These dark features on the slopes are called "recurring slope lineae" or RSL. Planetary scientists using observations with the Compact Reconnaissance Imaging Spectrometer on the same orbiter detected hydrated salts on these slopes at Hale Crater, corroborating the hypothesis that the streaks are formed by briny liquid water.

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 a false-color image over the land-shape model. The vertical dimension is exaggerated by a factor of 1.5 compared to horizontal dimensions. The camera records brightness in three wavelength bands: infrared, red and blue-green. The draped image is one product from HiRISE observation ESP_03070_1440.

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:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO),

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Journey to Mars

Sept. 26, 2015

Opportunity Mars Rover Preparing for Active Winter

This Martian scene shows contrasting textures and colors of "Hinners Point," at the northern edge of "Marathon Valley," and swirling reddish zones on the valley floor to the left.

Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Full image and caption

This stereo view from NASA's Mars Exploration Rover Opportunity shows contrasting textures and tones of "Hinners Point," at the northern edge of "Marathon Valley," and brighter outcrop on the valley floor to the left.

Credits: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Full image and caption

NASA's Mars Exploration Rover Opportunity is conducting a "walkabout" survey of "Marathon Valley," where the rover's operators plan to use the vehicle through the upcoming Martian winter, and beyond, to study the context for outcrops bearing clay minerals.

Marathon Valley slices downhill from west to east for about 300 yards or meters through the western rim of Endeavour Crater. Opportunity has been investigating rock targets in the western portion of the valley since late July, working its way eastward in a thorough reconnaissance of the area.

The rover's panoramic camera has captured a scene dominated by a summit called "Hinners Point," forming part of the valley's northern edge. The image also shows a portion of the valley floor with swirling reddish zones that have been a target for study. 

For several months starting in mid- to late October, the rover team plans to operate Opportunity on the southern side of the valley to take advantage of the sun-facing slope. The site is in Mars' southern hemisphere, so the sun is to the north during fall and winter days. Tilting the rover toward the sun increases power output from its solar panels. The shortest-daylight period of this seventh Martian winter for Opportunity will come in January 2016.

"Our expectation is that Opportunity will be able to remain mobile through the winter," said Mars Exploration Rover Project Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena, California.

The walkabout is identifying investigation targets in and near the valley floor. Rocks in reddish zones there contain more silica and less iron than most rocks in the area.

"We have detective work to do in Marathon Valley for many months ahead," said Opportunity Deputy Principal Investigator Ray Arvidson, of Washington University in St. Louis. "During the Martian late fall and winter seasons Opportunity will conduct its measurements and traverses on the southern side of the valley. When spring arrives the rover will return to the valley floor for detailed measurements of outcrops that may host the clay minerals."

Endeavour Crater spans about 14 miles (22 kilometers) in diameter. Opportunity has been studying its western rim since 2011. Marathon Valley became a high priority destination after a concentration of clay minerals called smectites was mapped there based on observations by the Compact Reconnaissance Imaging Spectrometer for Mars aboard NASA's Mars Reconnaissance Orbiter. Smectites form under wetter, milder conditions than most rocks at the Opportunity site. Opportunity is investigating relationships among clay-bearing and neighboring deposits for clues about the history of environmental changes.

The rover team has been dealing for more than a year with Opportunity's tendency to undergo unplanned computer resets when using the type of onboard memory that retains information when power is off: flash memory. For three months until mid-September, operators fully avoided use of flash memory. In this mode, images and other data cannot be stored overnight, when the rover is powered off to conserve energy. To gain operational flexibility in a trade-off with possible "lost" days from resets, the team has resumed occasional use of flash memory.

NASA's Mars Exploration Rover Project landed twin rovers Spirit and Opportunity on Mars in 2004 to begin missions planned to last three months. Both rovers far exceeded those plans. Spirit worked for six years, and Opportunity is still active. Findings about ancient wet environments on Mars have come from both rovers. The project is one element of NASA's ongoing and future Mars missions preparing for a human mission to the planet in the 2030s. JPL, a division of the California Institute of Technology, manages the project for NASA's Science Mission Directorate in Washington.

For more information about Opportunity, visit:

http://www.nasa.gov/rovers

http://marsrovers.jpl.nasa.gov

Follow the project on Twitter and Facebook at:

http://twitter.com/MarsRovers

http://www.facebook.com/mars.rovers

Last Updated: Sept. 26, 2015

Editor: Tony Greicius

Tags:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Exploration Rovers (Spirit and Opportunity), Solar System,

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Journey to Mars

Sept. 25, 2015

M15-145

NASA to Announce Mars Mystery Solved

Sept. 28 Update: NASA Confirms Evidence That Liquid Water Flows on Today's Mars

Mars true-color globe showing Terra Meridiani.

Credits: NASA/Greg Shirah

(Nature Geoscience has Embargoed Details until 11 a.m. EDT Sept. 28)

NASA will detail a major science finding from the agency’s ongoing exploration of Mars during a news briefing at 11:30 a.m. EDT on Monday, Sept. 28 at the James Webb Auditorium at NASA Headquarters in Washington. The event will be broadcast live on NASA Television and the agency's website.

News conference participants will be: 

·         Jim Green, director of planetary science at NASA Headquarters

·         Michael Meyer, lead scientist for the Mars Exploration Program at NASA Headquarters

·         Lujendra Ojha of the Georgia Institute of Technology in Atlanta

·         Mary Beth Wilhelm of NASA’s Ames Research Center in Moffett Field, California and the Georgia Institute of Technology

·         Alfred McEwen, principal investigator for the High Resolution Imaging Science Experiment (HiRISE) at the University of Arizona in Tucson

A brief question-and-answer session will take place during the event with reporters on site and by phone. Members of the public also can ask questions during the briefing using #AskNASA.

To participate in the briefing by phone, reporters must email their name, media affiliation and telephone number to Steve Cole at stephen.e.cole@nasa.gov by 9 a.m. EDT on Monday.

For NASA TV downlink information, schedules and to view the news briefing, visit:

http://www.nasa.gov/nasatv

For more information about NASA's journey to Mars:

https://www.nasa.gov/topics/journeytomars

-end-

Dwayne Brown / Laurie Cantillo
Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

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

Last Updated: Sept. 29, 2015

Editor: Gina Anderson

Tags:  Ames Research Center, Journey to Mars,

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Mars Curiosity

Sept. 12, 2015

Mars Panorama from Curiosity Shows Petrified Sand Dunes

Large-scale crossbedding in the sandstone of this ridge on a lower slope of Mars' Mount Sharp is typical of windblown sand dunes that have petrified. NASA's Curiosity Mars rover used its Mastcam to capture this vista on Aug. 27, 2015. Similarly textured sandstone is common in the U.S. Southwest.

Credits: NASA/JPL-Caltech/MSSS

Full image and caption

Some of the dark sandstone in an area being explored by NASA's Curiosity Mars rover shows texture and inclined bedding structures characteristic of deposits that formed as sand dunes, then were cemented into rock.

A panorama from Curiosity's Mast Camera (Mastcam) that includes a ridge made of this sandstone is online at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA19818

This sandstone outcrop -- part of a geological layer that Curiosity's science team calls the Stimson unit -- has a structure called crossbedding on a large scale that the team has interpreted as deposits of sand dunes formed by wind. Similar-looking petrified sand dunes are common in the U.S. Southwest. Geometry and orientation of the crossbedding give information about the directions of the winds that produced the dunes.

The Stimson unit overlies a layer of mudstone that was deposited in a lake environment. Curiosity has been examining successively higher and younger layers of Mount Sharp, starting with the mudstone at the mountain's base, for evidence about changes in the area's ancient environment.

The dozens of individual Mastcam images combined into this panorama were taken on Aug. 27, 2015. Curiosity has driven about 103 yards (94 meters) in the subsequent two weeks, generally southward. Outcrops of the Stimson unit sandstone are still accessible to the rover, and researchers plan to use the rover to collect and analyze a drilled sample of Stimson unit sandstone this month.

Curiosity has been working on Mars since early August 2012. It reached the base of Mount Sharp last year after fruitfully investigating outcrops closer to its landing site and then trekking to the mountain.

Malin Space Science Systems, San Diego, built and operates the rover's Mastcam. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover. For more information about Curiosity, visit:

http://www.nasa.gov/msl

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

You can follow the mission on Facebook and Twitter at:

http://www.facebook.com/marscuriosity

http://www.twitter.com/marscuriosity

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

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

2015-296

Last Updated: Sept. 12, 2015

Editor: Tony Greicius

Tags:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Science Laboratory (Curiosity), Solar System,

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MRO

Sept. 3, 2015

What Happened to Early Mars' Atmosphere? New Study Eliminates one Theory

This view combines information from two instruments on a NASA Mars orbiter to map color-coded composition over the shape of the ground within the Nili Fossae plains region of Mars. Carbonate-rich deposits in this area (coded green) hold some carbon formerly in the atmosphere's carbon dioxide.

Credits: NASA/JPL-Caltech/JHUAPL/Univ. of Arizona

Full image and caption

Researchers estimating the amount of carbon held in the ground at the largest known carbonate-containing deposit on Mars utilized data from five instruments on three different NASA Mars orbiters, including physical properties from THEMIS (left) and mineral information from CRISM (right).

Credits: NASA/JPL-Caltech/ASU/JHUAPL

Full image and caption

Scientists may be closer to solving the mystery of how Mars changed from a world with surface water billions of years ago to the arid Red Planet of today.

A new analysis of the largest known deposit of carbonate minerals on Mars suggests that the original Martian atmosphere may have already lost most of its carbon dioxide by the era of valley network formation.

"The biggest carbonate deposit on Mars has, at most, twice as much carbon in it as the current Mars atmosphere," said Bethany Ehlmann of the California Institute of Technology and NASA Jet Propulsion Laboratory, both in Pasadena. "Even if you combined all known carbon reservoirs together, it is still nowhere near enough to sequester the thick atmosphere that has been proposed for the time when there were rivers flowing on the Martian surface."

Carbon dioxide makes up most of the Martian atmosphere. That gas can be pulled out of the air and sequestered or pulled into the ground by chemical reactions with rocks to form carbonate minerals. Years before the series of successful Mars missions, many scientists expected to find large Martian deposits of carbonates holding much of the carbon from the planet's original atmosphere. Instead, these missions have found low concentrations of carbonate distributed widely, and only a few concentrated deposits. By far the largest known carbonate-rich deposit on Mars covers an area at least the size of Delaware, and maybe as large as Arizona, in a region called Nili Fossae.

Christopher Edwards, a former Caltech researcher now with the U.S. Geological Survey in Flagstaff, Arizona, and Ehlmann reported the findings and analysis in a paper posted online by the journal Geology. Their estimate of how much carbon is locked into the Nili Fossae carbonate deposit uses observations from numerous Mars missions, including the Thermal Emission Spectrometer (TES) on NASA's Mars Global Surveyor orbiter, the mineral-mapping Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) and two telescopic cameras on NASA's Mars Reconnaissance Orbiter, and the Thermal Emission Imaging System (THEMIS) on NASA's Mars Odyssey orbiter.

Edwards and Ehlmann compare their tally of sequestered carbon at Nili Fossae to what would be needed to account for an early Mars atmosphere dense enough to sustain surface waters during the period when flowing rivers left their mark by cutting extensive river-valley networks. By their estimate, it would require more than 35 carbonate deposits the size of the one examined at Nili Fossae. They deem it unlikely that so many large deposits have been overlooked in numerous detailed orbiter surveys of the planet. While deposits from an even earlier time in Mars history could be deeper and better hidden, they don't help solve the thin-atmosphere conundrum at the time the river-cut valleys formed.

The modern Martian atmosphere is too tenuous for liquid water to persist on the surface. A denser atmosphere on ancient Mars could have kept water from immediately evaporating. It could also have allowed parts of the planet to be warm enough to keep liquid water from freezing. But if the atmosphere was once thicker, what happened to it? one possible explanation is that Mars did have a much denser atmosphere during its flowing-rivers period, and then lost most of it to outer space from the top of the atmosphere, rather than by sequestration in minerals.

"Maybe the atmosphere wasn't so thick by the time of valley network formation," Edwards said. "Instead of Mars that was wet and warm, maybe it was cold and wet with an atmosphere that had already thinned. How warm would it need to have been for the valleys to form? Not very. In most locations, you could have had snow and ice instead of rain. You just have to nudge above the freezing point to get water to thaw and flow occasionally, and that doesn't require very much atmosphere." 

NASA's Curiosity Mars rover mission has found evidence of ancient top-of-atmosphere loss, based on the modern Mars atmosphere's ratio of heavier carbon to lighter carbon. Uncertainty remains about how much of that loss occurred before the period of valley formation; much may have happened earlier. NASA's MAVEN orbiter, examining the outer atmosphere of Mars since late 2014, may help reduce that uncertainty.

Arizona State University, Tempe, provided the TES and THEMIS instruments. The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland., provided CRISM. JPL, a division of Caltech, manages the Mars Reconnaissance Orbiter and Mars Odyssey project for NASA's Science Mission Directorate, Washington, and managed the Mars Global Surveyor project through its nine years of orbiter operations at Mars. Lockheed Martin Space Systems in Denver built the three orbiters.

For more information about the Mars Reconnaissance Orbiter mission, visit:

http://mars.nasa.gov/mro

For more information about the Mars Odyssey mission, visit:

http://mars.nasa.gov/odyssey

Last Updated: Sept. 3, 2015

Editor: Tony Greicius

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

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Mars Curiosity

Aug. 20, 2015

NASA Mars Rover Moves onward After 'Marias Pass' Studies

This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle at the site from which it reached down to drill into a rock target called "Buckskin." The MAHLI camera on Curiosity's robotic arm took multiple images on Aug. 5, 2015, that were stitched together into this selfie.

Credits: NASA/JPL-Caltech/MSSS

Full image and caption

This version of a self-portrait of NASA's Curiosity Mars rover at a drilling site called "Buckskin" is presented as a stereographic projection, which shows the horizon as a circle. The MAHLI camera on Curiosity's robotic arm took dozens of component images for this selfie on Aug. 5, 2015.

Credits: NASA/JPL-Caltech/MSSS

Full image and caption

This low-angle self-portrait of NASA's Curiosity Mars rover from Aug. 5, 2015, shows the vehicle above the "Buckskin" rock target in the "Marias Pass" area of lower Mount Sharp. The MAHLI camera on Curiosity's robotic arm took dozens of images that were stitched together into this sweeping panorama.

Credits: NASA/JPL-Caltech/MSSS

Full image and caption

This view of a test rover at NASA's Jet Propulsion Laboratory in California results from advance testing of arm positions and camera pointings for taking a low-angle selfie of NASA's Curiosity Mars rover.

Credits: NASA/JPL-Caltech/MSSS

Full image and caption

Curiosity's DAN instrument for checking hydration levels in the ground beneath the rover detected an unusually high amount at a site near "Marias Pass," prompting repeated passes over the area to map the hydrogen amounts. This map shows color-coded results from multiple traverses over the area.

Credits: NASA/JPL-Caltech/Russian Space Research Institute

Full image and caption

NASA's Curiosity Mars rover is driving toward the southwest after departing a region where for several weeks it investigated a geological contact zone and rocks that are unexpectedly high in silica and hydrogen content. The hydrogen indicates water bound to minerals in the ground.

In this "Marias Pass" region, Curiosity successfully used its drill to sample a rock target called "Buckskin" and then used the camera on its robotic arm for multiple images to be stitched into a self-portrait at the drilling site. The new Curiosity selfie from a dramatically low angle is online at:

http://www.jpl.nasa.gov/spaceimages/details.php?id=pia19808

The rover finished activities in Marias Pass on Aug. 12 and headed onward up Mount Sharp, the layered mountain it reached in September 2014. In drives on Aug. 12, 13, 14 and 18, it progressed 433 feet (132 meters), bringing Curiosity's total odometry since its August 2012 landing to 6.9 miles (11.1 kilometers).

Curiosity is carrying with it some of the sample powder drilled from Buckskin. The rover's internal laboratories are analyzing the material. The mission's science team members seek to understand why this area bears rocks with significantly higher levels of silica and hydrogen than other areas the rover has traversed.

Silica, monitored with Curiosity's laser-firing Chemistry and Camera (ChemCam) instrument, is a rock-forming chemical containing silicon and oxygen, commonly found on Earth as quartz. Hydrogen in the ground beneath the rover is monitored by the rover's Dynamic Albedo of Neutrons (DAN) instrument. It has been detected at low levels everywhere Curiosity has driven and is interpreted as the hydrogen in water molecules or hydroxyl ions bound within or absorbed onto minerals in the rocks and soil.

"The ground about 1 meter beneath the rover in this area holds three or four times as much water as the ground anywhere else Curiosity has driven during its three years on Mars," said DAN Principal Investigator Igor Mitrofanov of Space Research Institute, Moscow. DAN first detected the unexpectedly high level of hydrogen using its passive mode. Later, the rover drove back over the area using DAN in active mode, in which the instrument shoots neutrons into the ground and detects those that bounce off the subsurface, but preferentially interacting with hydrogen. The measurements confirmed hydrated material covered by a thin layer of drier material.

Curiosity initially noted the area with high silica and hydrogen on May 21 while climbing to a site where two types of sedimentary bedrock lie in contact with each other. Such contact zones can hold clues about ancient changes in environment, from conditions that produced the older rock type to conditions that produced the younger one. This contact is the lure that led the rover team to choose Marias Pass as a route toward higher layers of Mount Sharp. Pale mudstone, like bedrock the mission examined for the first several months after reaching Mount Sharp at an area called "Pahrump Hills," forms one side of the contact. The overlying side is darker, finely bedded sandstone.

Curiosity examined the Marias Pass contact zone closely with instruments mounted on its mast and arm. The unusual levels of silica and hydrogen in rocks passed during the climb prompted a choice to backtrack to examine that area and acquire a drilled sample.

Buckskin was the first rock drilled by Curiosity since an electrical circuit in the drill's percussion mechanism exhibited a small, transient short circuit in February during transfer of sample powder from the third target drilled in the Pahrump Hills area.

"We were pleased to see no repeat of the short circuit during the Buckskin drilling and  sample transfer," said Steven Lee, deputy project manager for Curiosity at NASA's Jet Propulsion Laboratory, Pasadena, California. "It could come back, but we have made changes in fault protection to continue safely drilling even in the presence of small shorts. We also improved drill percuss circuit telemetry to gain more diagnostic information from any future occurrences."

Curiosity reached the base of Mount Sharp after two years of fruitfully investigating outcrops closer to its landing site and trekking to the mountain. The main mission objective now is to examine layers of lower Mount Sharp for ancient habitable environments and evidence about how early Mars environments evolved from wetter to drier conditions.

JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit:

http://www.nasa.gov/msl

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

You can follow the mission on Facebook and Twitter at:

http://www.facebook.com/marscuriosity

http://www.twitter.com/marscuriosity

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

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

2015-271

Last Updated: Aug. 20, 2015

Editor: Tony Greicius

Tags:  Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Science Laboratory (Curiosity), Solar System,

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MRO

Aug. 13, 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. 13, 2015

Editor: Tony Greicius

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

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MRO

Aug. 12, 2015

One Decade after Launch, Mars Orbiter Still Going Strong

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, possibly shallow seeps of salty water. This July 21, 2015, image from the orbiter's HiRISE camera shows examples within Mars' Valles Marineris.

Credits: NASA/JPL-Caltech/Univ. of Arizona

Full image and caption

Ten years after launch, NASA’s Mars Reconnaissance Orbiter (MRO) has revealed the Red Planet’s diversity and activity, returning more data about Mars every week than the weekly total from all six other active Mars missions. And its work is far from over.   

The workhorse orbiter now plays a key role in NASA’s Journey to Mars planning. Images from the orbiter, revealing details as small as a desk, aid the analysis of potential landing sites for the 2016 InSight lander and Mars 2020 rover. Data from the orbiter will also be used as part of NASA’s newly announced process to examine and select candidate sites where humans will first explore the Martian surface in the 2030s. 

An Atlas V rocket launched the orbiter on an early Florida morning from Cape Canaveral Air Force Station on Aug. 12, 2005, propelling it on a course toward Mars.

"The most crucial event after launch was orbit insertion on March 10, 2006," said JPL's Dan Johnston, MRO project manager. "The 27-minute burn of the spacecraft's main engines, necessary for orbit capture, was scheduled for completion while the spacecraft was behind Mars, so we had to wait in suspense for confirmation that it went well. It did. As planned, the initial orbit was highly elliptical. Then we had nearly five months of aerobraking -- using controlled friction of more than 400 dips into the upper fringe of the atmosphere -- to shrink the orbit to a nearly circular shape.”

MRO's primary science mission began in November 2006 and lasted for one Mars year, equivalent to about two Earth years. The orbiter has used six instruments to examine Mars' surface, subsurface and atmosphere. The spacecraft has been orbiting Mars at an altitude of about 186 miles (300 kilometers) above the Red Planet, passing near the north and south poles about 12 times a day.

"Mars Reconnaissance Orbiter has found evidence of diverse watery environments on early Mars, some more habitable than others," said the mission's project scientist, Rich Zurek of NASA's Jet Propulsion Laboratory, Pasadena, California. "MRO has discovered that Mars' south polar cap holds enough buried carbon-dioxide ice to double the planet's current atmosphere if it warmed. It’s caught avalanches and dust storms in action. The spacecraft's longevity has made it possible to study seasonal and longer-term changes over four Martian years. These studies document activity such as moving dunes, freshly excavated impact craters -- some which expose subsurface ice -- and mysterious strips that darken and fade with the seasons and are best explained as brine flows." 

Though it has already served longer than planned, the spacecraft could remain a cornerstone of NASA's Mars Exploration Program fleet for years to come.

In addition to continuing to make its own discoveries about Mars, the mission delivers crucial support for surface-based missions. This support includes communication relay service and detailed observations of candidate landing sites for rovers and stationary landers past, present and future.

"Ten years after launch, MRO continues full science and relay operations," said Kevin Gilliland, spacecraft engineer for the mission at Lockheed Martin Space Systems, Denver. "We've kept our operations efficient. We've been able to bring back an astonishing amount of science data -- more than 250 terabits so far. Even after more than 40,000 orbits, the mission remains exciting, with new challenges such as taking close-up images of a passing comet last year and supporting next year's InSight landing."

The InSight mission will place a lander on Mars to investigate the deep interior of the Red Planet for clues about the formation and evolution of all rocky planets, including Earth. A maneuver two weeks ago altered MRO's orbit, as planned, to put it in position to provide communication support for InSight's Sept. 28, 2016, landing. 

JPL, 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 built the orbiter and collaborates with JPL to operate it.

More information about NASA's Journey to Mars is available online at:

https://www.nasa.gov/topics/journeytomars

For more information about MRO, visit:

http://www.nasa.gov/mro

http://mars.nasa.gov/mro

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

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

2015-264     

Last Updated: Aug. 13, 2015

Editor: Tony Greicius

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

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Journey to Mars

Aug. 6, 2015

15-164

New online Exploring Tools Bring NASA's Journey to Mars to New Generation

A screen capture from NASA's new Experience Curiosity website shows the rover in the process of taking its own self-portrait. Users can view Mars through the eyes of the rover, using the window in the lower, right corner. The control panel at left helps users navigate the rover itself, and relive some of its actual expeditions on Mars. Visit the website online at: http://eyes.nasa.gov/curiosity/ .

Credits: NASA/JPL-Caltech

On the three-year anniversary of the Mars landing of NASA’s Curiosity rover, NASA is unveiling two new online tools that open the mysterious terrain of the Red Planet to a new generation of explorers, inviting the public to help with its journey to Mars.

Mars Trek is a free, web-based application that provides high-quality, detailed visualizations of the planet using real data from 50 years of NASA exploration and allowing astronomers, citizen scientists and students to study the Red Planet’s features.

A panorama combining images from both cameras of the Mastcam on NASA's Curiosity Mars Rover shows diverse geological textures on Mount Sharp. Three years after landing on Mars, the mission is investigating this layered mountain for evidence about changes in Martian environmental conditions.

Credits: NASA/JPL-Caltech/MSSS

Experience Curiosity allows viewers to journey along with the one-ton rover on its Martian expeditions. The program simulates Mars in 3-D based on actual data from Curiosity and NASA's Mars Reconnaissance Orbiter (MRO), giving users first-hand experience in a day in the life of a Mars rover.

A NASA team already is using Mars Trek to aid in the selection of possible landing sites for the agency’s Mars 2020 rover, and the application will be used as part of NASA’s newly-announced process to examine and select candidate sites for the first human exploration mission to Mars in the 2030s. 

“This tool has opened my eyes as to how we should first approach roaming on another world, and now the public can join in on the fun,” said Jim Green, director of NASA’s Planetary Science Division in Washington. “Our robotic scientific explorers are paving the way, making great progress on the journey to Mars. Together, humans and robots will pioneer Mars and the solar system."

Mars Trek has interactive maps, which include the ability to overlay a range of data sets generated from instruments aboard spacecraft orbiting Mars, and analysis tools for measuring surface features. Standard keyboard gaming controls are used to maneuver the users across Mars’ surface and 3-D printer-exportable topography allows users to print physical models of surface features.

Mars Trek was developed by NASA's Lunar Mapping and Modeling Project, which provides mission planners, lunar scientists and the public with analysis and data visualization tools for our moon. LMMP is managed by NASA's Solar System Exploration Research Virtual Institute at NASA's Ames Research Center in Moffett Field, California.

Experience Curiosity also uses real science data to create a realistic and game-ready rover model based entirely on real mechanisms and executed commands. Users can manipulate the rover’s tools and view Mars through each of its cameras.

NASA's Curiosity Mars Rover drilled this hole to collect sample material from a rock target called "Buckskin" on July 30, 2015, about a week prior to the third anniversary of the rover's landing on Mars. The diameter is slightly smaller than a U.S. dime.

Credits: NASA/JPL-Caltech/MSSS

"We've done a lot of heavy 3-D processing to make Experience Curiosity work in a browser. Anybody with access to the web can take a journey to Mars," said Kevin Hussey, manager of the Visualization Applications and Development group at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, which manages and operates the Curiosity rover.

Curiosity's adventures on the Red Planet began in the early morning hours of Aug. 6, 2012, Eastern time (evening of Aug. 5, Pacific time), when a landing technique called the sky-crane maneuver deposited the rover in the 96-mile-wide Gale Crater. From there, the rover began investigating its new home, discovering it had landed near an ancient lakebed sprinkled with organic material. Billions of years ago, fresh water would have flowed into this lake, offering conditions favorable for microbial life.

"At three years old, Curiosity already has had a rich and fascinating life. This new program lets the public experience some of the rover's adventures first-hand," said Jim Erickson, the project manager for the mission at JPL.

NASA has been on Mars for five decades with robotic explorers, and August traditionally has been a busy month for exploration of the planet. Viking 2 was put into orbit around Mars 39 years ago on Aug. 7, 1976, making NASA’s second successful landing on the Martian surface weeks later. MRO was launched on Aug. 12, 2005 and still is in operation orbiting Mars. And, Tuesday, Aug. 4 marked the eight-year anniversary of the launch of the Phoenix mission to the north polar region of the Red Planet.

NASA’s orbiters and rovers have changed the way we look at Mars and enable continued scientific discoveries that one day will pave the way for astronauts to explore the Red Planet.

More information about NASA's journey to Mars is available online at:

https://www.nasa.gov/topics/journeytomars

For more information about Curiosity, visit:

http://www.nasa.gov/msl

To download and print a 3-D model of Curiosity, go to:

http://nasa3d.arc.nasa.gov/detail/mars-rover-curiosity

-end-

Dwayne Brown / Laurie Cantillo
Headquarters, Washington                                                                      
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

Guy Webster / Whitney Clavin
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278 / 818-354-4673
guy.w.webster@jpl.nasa.gov / whitney.clavin@jpl.nasa.gov

Darryl Waller
Ames Research Center, Moffett Field, Calif.
650-604-4789
darryl.e.waller@nasa.gov

Last Updated: Aug. 6, 2015

Editor: Gina Anderson

Tags:  Ames Research Center, Journey to Mars, Mars Science Laboratory (Curiosity),

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InSight Mars Lander

July 29, 2015

NASA Mars Orbiter Preparing for Mars Lander's 2016 Arrival

This artist's concept shows NASA's Mars Reconnaissance Orbiter mission over the red planet.

Credits: NASA/JPL-Caltech

UPDATED: July 29, 2014  (4:10 p.m. PT)
NASA's Mars Reconnaissance Orbiter successfully completed a maneuver on July 29, 2015, to put the spacecraft in the right place on Sept. 28, 2016, for supporting arrival of the InSight Mars lander mission. The maneuver's engine burn began at 6:21:31 a.m. PDT (13:21:31 UTC) and lasted for 75 seconds. 

With its biggest orbit maneuver since 2006, NASA's Mars Reconnaissance Orbiter (MRO) will prepare this week for the arrival of NASA's next Mars lander, InSight, next year.

A planned 77-second firing of six intermediate-size thrusters on July 29 will adjust the orbit timing of the veteran spacecraft so it will be in position to receive radio transmissions from InSight as the newcomer descends through the Martian atmosphere and touches down on Sept. 28, 2016. These six rocket engines, which were used for trajectory corrections during the spacecraft's flight from Earth to Mars, can each produce about 22 newtons, or five pounds, of thrust.

"Without making this orbit change maneuver, Mars Reconnaissance Orbiter would be unable to hear from InSight during the landing, but this will put us in the right place at the right time," said MRO Project Manager Dan Johnston of NASA's Jet Propulsion Laboratory, Pasadena, California.

The orbiter will record InSight's transmissions for later playback to Earth as a record of each event during the critical minutes of InSight's arrival at Mars, just as MRO did for the landings of NASA's Curiosity Mars rover three years ago, and NASA's Phoenix Mars lander in 2008.

InSight will examine the deep interior of Mars for clues about the formation and early evolution of all rocky planets, including Earth.

MRO will continue its studies of Mars while preparing for the InSight arrival. MRO collects high-resolution imaging and spectral data, as well as atmospheric and sub-surface profiles. It has returned several times more data about the Red Planet than all other deep-space missions combined. It will also continue providing communication relay support for Mars rovers and making observations for analysis of candidate landing sites for future missions.

After the InSight landing, plans call for MRO to perform a pair of even larger maneuvers in October 2016 and April 2017 -- each using the six intermediate-size thrusters longer than three minutes. These will return it to the orbit timing it has used since 2006, crossing the equator at about 3 a.m. and 3 p.m., local solar time, during each near-polar loop around the planet. To observe the InSight arrival, MRO will be in an orbit that crosses the equator at about 2:30 p.m. local solar mean time.

The last time the mission performed a maneuver larger than this week's was on November 15, 2006. That maneuver fired the intermediate-size thrusters for 76 seconds to establish the original 3 p.m. Local Mean Solar Time (LMST) sun-synchronous condition after a six-month period of using dips into the upper atmosphere to alter the orbit's shape. The spacecraft has three sets of thrusters. It used its most powerful set -- six thrusters, each with 170 newtons, or 39 pounds of force -- for about 27 minutes to first enter orbit when it arrived at Mars on March 10, 2006. It uses eight smaller thrusters most frequently, for small adjustments to course or orientation.

Even after the planned 2017 maneuver, the spacecraft's remaining supply of hydrazine propellant is projected to be more than 413 pounds (about 187 kilograms), equivalent to about 19 years of consumption in normal operations.

JPL, a division of the California Institute of Technology in Pasadena, manages the MRO Project for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems in Denver built the orbiter and supports its operations. For more information about MRO, visit:

http://www.nasa.gov/mro

http://mars.nasa.gov/mro

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

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

2015-249

Last Updated: July 31, 2015

Editor: Tony Greicius

Tags:  InSight Mars Lander, Jet Propulsion Laboratory, Journey to Mars, Mars, Mars Reconnaissance Orbiter (MRO), Solar System,

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Distant Planets

July 24, 2015

Finding Another Earth

A newly discovered exoplanet, Kepler-452b, comes the closest of any found so far to matching our Earth-sun system. This artist’s conception of a planetary lineup shows habitable-zone planets with similarities to Earth: from left, Kepler-22b, Kepler-69c, the just announced Kepler-452b, Kepler-62f and Kepler-186f. Last in line is Earth itself.

Credits: NASA/Ames/JPL-Caltech

Of the 1,030 confirmed planets from Kepler, a dozen are less than twice the size of Earth and reside in the habitable zone of their host stars. In this diagram, the sizes of the exoplanets are represented by the size of each sphere. These are arranged by size from left to right, and by the type of star they orbit, from the M stars that are significantly cooler and smaller than the sun, to the K stars that are somewhat cooler and smaller than the sun, to the G stars that include the sun. The sizes of the planets are enlarged by 25 times compared to the stars. The Earth is shown for reference.

Credits: NASA/Ames/JPL-Caltech

The discovery of a super-Earth-sized planet orbiting a sun-like star brings us closer than ever to finding a twin of our own watery world. But NASA’s Kepler space telescope has captured evidence of other potentially habitable planets amid the sea of stars in the Milky Way galaxy.

To take a brief tour of the more prominent contenders, it helps to zero in on the “habitable zone” around their stars. This is the band of congenial temperatures for planetary orbits -- not too close and not too far. Too close and the planet is fried (we’re looking at you, Venus). Too far and it’s in deep freeze. But settle comfortably into the habitable zone, and your planet could have liquid water on its surface -- just right. Goldilocks has never been more relevant. Scientists have, in fact, taken to calling this water-friendly region the “Goldilocks zone.”

The zone can be a wide band or a narrow one, and nearer the star or farther, depending on the star’s size and energy output. For small, red-dwarf stars, habitable zone planets might gather close, like marshmallow-roasting campers around the fire. For gigantic, hot stars, the band must retreat to a safer distance.

About a dozen habitable zone planets in the Earth-size ballpark have been discovered so far -- that is, 10 to 15 planets between one-half and twice the diameter of Earth, depending on how the habitable zone is defined and allowing for uncertainties about some of the planetary sizes.

The new discovery, Kepler-452b, fires the planet hunter’s imagination because it is the most similar to the Earth-sun system found yet: a planet at the right temperature within the habitable zone, and only about one-and-a-half times the diameter of Earth, circling a star very much like our own sun. The planet also has a good chance of being rocky, like Earth, its discoverers say.

Kepler-452b is more similar to Earth than any system previously discovered. And the timing is especially fitting: 2015 marks the 20th anniversary of the first exoplanet confirmed to be in orbit around a typical star.

But several other exoplanet discoveries came nearly as close in their similarity to Earth.

Before this, the planet Kepler-186f held the “most similar” distinction (they get the common moniker, “Kepler,” because they were discovered with the Kepler space telescope). About 500 light-years from Earth, Kepler-186f is no more than 10 percent larger than Earth, and sails through its star’s habitable zone, making its surface potentially watery.

But its 130-day orbit carries it around a red-dwarf star that is much cooler than our sun and only half its size. Thus, the planet is really more like an “Earth cousin,” says Thomas Barclay of the Bay Area Environmental Research Institute at NASA’s Ames Research Center, Moffett Field, California, a co-author of the paper announcing the discovery in April 2014.

Kepler-186f gets about one-third the energy from its star that Earth gets from our sun. And that puts it just at the outside edge of the habitable zone. Scientists say that if you were standing on the planet at noon, the light would look about as bright as it does on Earth an hour before sunset.

That doesn’t mean the planet is bereft of life, although it doesn’t mean life exists there, either.

Before Kepler-186f, Kepler-62f was the exoplanet known to be most similar to Earth. Like the new discovery, Kepler-62f is a “super Earth,” about 40 percent larger than our home planet. But, like Kepler-186f, its 267-day orbit also carries it around a star that is cooler and smaller than the sun, some 1,200 light-years away in the constellation Lyra. Still, Kepler-62f does reside in the habitable zone.

Kepler-62f’s discovery was announced in April 2013, about the same time as Kepler-69c, another super Earth -- though one that is 70 percent larger than our home planet. That’s the bad news; astronomers are uncertain about the planet’s composition, or just when a “super Earth” becomes so large that it diminishes the chance of finding life on its surface. That also moves it farther than its competitors from the realm of a potential Earth twin. The good news is that Kepler-69c lies in its sun’s habitable zone, with a 242-day orbit reminiscent of our charbroiled sister planet, Venus. Its star is also similar to ours in size with about 80 percent of the sun’s luminosity. Its planetary system is about 2,700 light-years away in the constellation Cygnus.

Kepler-22b also was hailed in its day as the most like Earth. It was the first of the Kepler planets to be found within the habitable zone, and it orbits a star much like our sun. But Kepler-22b is a sumo wrestler among super Earths, about 2.4 times Earth’s size. And no one knows if it is rocky, gaseous or liquid. The planet was detected almost immediately after Kepler began making observations in 2009, and was confirmed in 2011. This planet, which could have a cloudy atmosphere, is 600 light-years away, with a 290-day orbit not unlike Earth’s.

Not all the planets jostling to be most like Earth were discovered using Kepler. A super Earth known as Gliese 667Cc also came to light in 2011, discovered by astronomers combing through data from the European Southern Observatory’s 3.6-meter telescope in Chile. The planet, only 22 light-years away, has a mass at least 4.5 times that of Earth. It orbits a red dwarf in the habitable zone, though closely enough -- with a mere 28-day orbit -- to make the planet subject to intense flares that could erupt periodically from the star’s surface. Still, its sun is smaller and cooler than ours, and Gliese 667Cc’s orbital distance means it probably receives around 90 percent of the energy we get from the sun. That’s a point in favor of life, if the planet’s atmosphere is something like ours. The planet’s true size and density remain unknown, however, which means it could still turn out to be a gas planet, hostile to life as we know it. And powerful magnetic fluxes also could mean periodic drop-offs in the amount of energy reaching the planet, by as much as 40 percent. These drop-offs could last for months, according to scientists at the University of Oslo’s Institute of Theoretical Astrophysics in Norway.

Deduct two points.

Too big, too uncertain, or circling the wrong kind of star: Shuffle through the catalog of habitable zone planets, and the closest we can come to Earth -- at least so far -- appears to be the new kid on the interstellar block, Kepler-452b.

NASA's Ames Research Center in Moffett Field, California, manages the Kepler and K2 missions for NASA's Science Mission Directorate. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corp. operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

JPL is managed by The California Institute of Technology for NASA.

More information about Kepler is online at:

http://www.nasa.gov/kepler

More information about NASA's planet-hunting efforts is online at:

http://planetquest.jpl.nasa.gov

A related news release about Kepler's latest planetary find is online at: http://www.nasa.gov/press-release/nasa-kepler-mission-discovers-bigger-older-cousin-to-earth

Written by Pat Brennan, PlanetQuest

Whitney Clavin
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-4673
whitney.clavin@jpl.nasa.gov

2015-244

Last Updated: July 31, 2015

Editor: Tony Greicius

Tags:  Ames Research Center, Distant Planets, Galaxies, Jet Propulsion Laboratory, Kepler and K2, Universe,

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Kepler and K2

July 23, 2015

15-156

NASA’s Kepler Mission Discovers Bigger, Older Cousin to Earth

This artist's concept compares Earth (left) to the new planet, called Kepler-452b, which is about 60 percent larger in diameter.

Credits: NASA/JPL-Caltech/T. Pyle

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This size and scale of the Kepler-452 system compared alongside the Kepler-186 system and the solar system. Kepler-186 is a miniature solar system that would fit entirely inside the orbit of Mercury.

Credits: NASA/JPL-CalTech/R. Hurt

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This artist's concept depicts one possible appearance of the planet Kepler-452b, the first near-Earth-size world to be found in the habitable zone of star that is similar to our sun.

Credits: NASA/JPL-Caltech/T. Pyle

Read more...

NASA's Kepler mission has confirmed the first near-Earth-size planet in the “habitable zone” around a sun-like star. This discovery and the introduction of 11 other new small habitable zone candidate planets mark another milestone in the journey to finding another “Earth.” 

The newly discovered Kepler-452b is the smallest planet to date discovered orbiting in the habitable zone -- the area around a star where liquid water could pool on the surface of an orbiting planet -- of a G2-type star, like our sun. The confirmation of Kepler-452b brings the total number of confirmed planets to 1,030.

on the 20th anniversary year of the discovery that proved other suns host planets, the Kepler exoplanet explorer has discovered a planet and star which most closely resemble the Earth and our Sun," said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at the agency’s headquarters in Washington. “This exciting result brings us one step closer to finding an Earth 2.0."Kepler-452b is 60 percent larger in diameter than Earth and is considered a super-Earth-size planet. While its mass and composition are not yet determined, previous research suggests that planets the size of Kepler-452b have a good chance of being rocky.

Highlighted are 12 new planet candidates from the seventh Kepler planet candidate catalog that are less than twice the size of Earth and orbit in the stars' habitable zone

Credits: NASA Ames/W. Stenzel

Twelve New Small Kepler Habitable Zone Candidates

There are 4,696 planet candidates now known with the release of the seventh Kepler planet candidate catalog - an increase of 521 since the release of the previous catalog in January 2015.

Credits: NASA/W. Stenzel

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While Kepler-452b is larger than Earth, its 385-day orbit is only 5 percent longer. The planet is 5 percent farther from its parent star Kepler-452 than Earth is from the Sun. Kepler-452 is 6 billion years old, 1.5 billion years older than our sun, has the same temperature, and is 20 percent brighter and has a diameter 10 percent larger.

“We can think of Kepler-452b as an older, bigger cousin to Earth, providing an opportunity to understand and reflect upon Earth’s evolving environment," said Jon Jenkins, Kepler data analysis lead at NASA's Ames Research Center in Moffett Field, California, who led the team that discovered Kepler-452b. "It’s awe-inspiring to consider that this planet has spent 6 billion years in the habitable zone of its star; longer than Earth. That’s substantial opportunity for life to arise, should all the necessary ingredients and conditions for life exist on this planet.”

To help confirm the finding and better determine the properties of the Kepler-452 system, the team conducted ground-based observations at the University of Texas at Austin's McDonald Observatory, the Fred Lawrence Whipple Observatory on Mt. Hopkins, Arizona, and the W. M. Keck Observatory atop Mauna Kea in Hawaii. These measurements were key for the researchers to confirm the planetary nature of Kepler-452b, to refine the size and brightness of its host star and to better pin down the size of the planet and its orbit.

The Kepler-452 system is located 1,400 light-years away in the constellation Cygnus. The research paper reporting this finding has been accepted for publication in The Astronomical Journal.

In addition to confirming Kepler-452b, the Kepler team has increased the number of new exoplanet candidates by 521 from their analysis of observations conducted from May 2009 to May 2013, raising the number of planet candidates detected by the Kepler mission to 4,696. Candidates require follow-up observations and analysis to verify they are actual planets.

Twelve of the new planet candidates have diameters between one to two times that of Earth, and orbit in their star's habitable zone. Of these, nine orbit stars that are similar to our sun in size and temperature.

“We've been able to fully automate our process of identifying planet candidates, which means we can finally assess every transit signal in the entire Kepler dataset quickly and uniformly,” said Jeff Coughlin, Kepler scientist at the SETI Institute in Mountain View, California, who led the analysis of a new candidate catalog. “This gives astronomers a statistically sound population of planet candidates to accurately determine the number of small, possibly rocky planets like Earth in our Milky Way galaxy.”

These findings, presented in the seventh Kepler Candidate Catalog, will be submitted for publication in the Astrophysical Journal. These findings are derived from data publicly available on the NASA Exoplanet Archive.

Scientists now are producing the last catalog based on the original Kepler mission’s four-year data set. The final analysis will be conducted using sophisticated software that is increasingly sensitive to the tiny telltale signatures of Earth-size planets.

Ames manages the Kepler and K2 missions for NASA’s Science Mission Directorate. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

For more information about the Kepler mission, visit:

http://www.nasa.gov/kepler

A related feature story about other potentially habitable planets is online at: http://www.nasa.gov/jpl/finding-another-earth

-end-

Felicia Chou
Headquarters, Washington
202-358-0257
felicia.chou@nasa.gov

Michele Johnson
Ames Research Center, Moffett Field, Calif.
650-604-6982
michele.johnson@nasa.gov

Links:

Briefing materials
Reporter package
Media Advisory

Last Updated: July 31, 2015

Editor: Michele Johnson

Tags:  Ames Research Center, Distant Planets, Jet Propulsion Laboratory, Kepler and K2, Universe,

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MRO

July 23, 2015

New Website Gathering Public Input on NASA Mars Images

This series of images from NASA's Mars Reconnaissance Orbiter successively zooms into "spider" features -- or channels carved in the surface in radial patterns -- in the south polar region of Mars. In a new citizen-science project, volunteers will identify features like these using wide-scale images from the orbiter. Their input will then help mission planners decide where to point the orbiter's high-resolution camera for more detailed views of interesting terrain.

Credits: NASA/JPL-Caltech/MSSS/Univ. of Arizona

Full image and caption

Science-team members for NASA's Mars Reconnaissance Orbiter are soliciting help from the public to analyze exotic features near the south pole of Mars.

By categorizing features visible in images from the orbiter's Context Camera (CTX), volunteers are using their own computers to help the team identify specific areas for even more detailed examination with the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera. HiRISE can reveal more detail than any other camera ever put into orbit around Mars.

Information about how to participate is at the "Planet Four: Terrains" website, at:

http://terrains.planetfour.org

Planet Four: Terrains is on a new platform released by the Zooniverse, an organization that currently hosts 30 projects that enlist people worldwide to contribute to discoveries in fields ranging from astronomy to zoology. The new platform is designed to make it easier than ever for a researcher needing help with data analysis to set up a task to involve volunteers.

Some of Mars resembles deserts on Earth, but Martian polar regions display some quite unearthly processes and features. These are related to seasonal freezing and thawing of carbon dioxide ice, which does not exist naturally on Earth, but is manufactured and well-known as "dry ice." Every winter the polar regions of Mars are covered with a seasonal polar cap of carbon-dioxide ice.

"In the spring the dry ice turns to gas and carves unusual features in the Mars surface, resulting in exotic terrains described informally as 'spiders,' 'Swiss cheese' and 'channel networks,'" said HiRISE Deputy Principal Investigator Candice Hansen, of the Planetary Science Institute, Tucson, Arizona.

On the Planet Four: Terrains website, volunteers review images from the south polar region of Mars and identify particular types of terrains. Each image from CTX covers a swath of ground about 16 miles (30 kilometers) wide, at a resolution of about 20 feet (6 meters) per pixel. The results from the citizen scientist input through Planet Four: Terrains will be used to target HiRISE for detailed seasonal studies beginning in mid-2016. Each HiRISE image covers a swath about 3.2 miles (five kilometers) wide, at a spatial scale of about 20 inches (half a meter) per pixel.

This new website is an outgrowth of the Planet Four initiative through which more than 120,000 citizen scientists have analyzed HiRISE image cutouts to measure fans that appear in the spring on the seasonal ice cap. The Planet Four website is at:

http://www.planetfour.org

More information about Zooniverse is available at:

http://www.zooniverse.org

With CTX, HiRISE and four other instruments, the Mars Reconnaissance Orbiter has been investigating Mars since 2006. The mission launched on Aug. 12, 2005, from Cape Canaveral Air Force Station, Florida.

Malin Space Science Systems, San Diego, built and operates CTX. The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp. of Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter Project NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, built the orbiter and collaborates with JPL to operate it. For additional information about the project, visit:

http://mars.nasa.gov/mro

Whitney Clavin 818-354-4673/Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
whitney.clavin@jpl.nasa.gov/guy.webster@jpl.nasa.gov

Alan Fischer 520-382-0411
Planetary Science Institute, Tucson, Ariz.
fischer@psi.edu

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

2015-243

Last Updated: July 31, 2015

Editor: Tony Greicius

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

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New Horizons

July 10, 2015

NASA Missions Have Their Eyes Peeled on Pluto

Artist conception of New Horizons Spacecraft.

Credits: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute

What's icy, has "wobbly" potato-shaped moons, and is arguably the world's favorite dwarf planet? The answer is Pluto, and NASA's New Horizons is speeding towards the edge of our solar system for a July 14 flyby. It won’t be making observations alone; NASA's fleet of observatories will be busy gathering data before and after to help piece together what we know about Pluto, and what features New Horizons data might help explain.  

"NASA is aiming some of our most powerful space observatories at Pluto,” said Paul Hertz, Astrophysics Division Director at NASA Headquarters, Washington. “With their unique capabilities combined, we will have a multi-faceted view of the Pluto system complementary to New Horizons data.”

Right around New Horizons’ closest approach to Pluto, Cassini will take an image of the dwarf planet from its station in orbit around Saturn. Although Cassini is the closest spacecraft to New Horizons’ distant location, the image of Pluto will be but a faint dot on a field of stars. Even so, the image will provide a scientific measurement of Pluto from a different vantage point that will complement data collected by New Horizons.

Who would expect tiny Pluto to generate X-rays? Soon after New Horizon’s encounter with Pluto, the Chandra X-ray Observatory will search for elusive low-energy X-rays produced when highly-charged solar wind ions collide with Pluto’s escaping neutral atmosphere. Together with data from the New Horizons Solar Wind at Pluto (SWAP) instrument, the detection of X-rays can potentially provide critical information on the rate at which Pluto’s atmosphere is escaping into interplanetary space. This data combination will allow scientists to test competing models of the planet’s atmosphere. The use of simultaneous X-ray and solar wind observations is a once-in-a-lifetime chance afforded by the impending New Horizons encounter to obtain fundamental insights into the working of this mysterious world.

“The Cassini team has been pleased to provide occasional imaging support for New Horizons for several years to aid with the Pluto-bound spacecraft’s navigation. It’s great to provide one last look at it soars through the Pluto system,” said Earl Maize, Cassini project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California.

Even after New Horizons flies past Pluto, the observations don't end there. on July 23, Spitzer Space Telescope will begin a seven-day series of observations, gathering infrared data at 18 different longitudes. The data will reveal possible changes in ice on Pluto's surface.

"Spitzer is around 4.87 billion km (around 3 billion miles) from Pluto,” said Noemi Pinella-Alonso from the University of Tennessee in Knoxville, and lead investigator of the Spitzer observations. “The spacecraft provides an effective tool to study the ice on the surface and search for other materials that have not yet been identified.”

Beginning in October, the Kepler spacecraft in its new mission, K2, will train its unceasing gaze on Pluto for nearly three months. Similar to how Kepler detected distant planets by measuring the change in brightness of their host star, K2 will record the change in the reflected light off Pluto and its nearest and largest moon Charon. Scientists will learn more about the effects on the atmosphere and surface of Pluto imparted by the dwarf planet's eccentric and expanding orbit about the sun. The data may also reveal seasonal changes on this chilly world.

"K2 observations will expand the time coverage of the speedy New Horizons' flyby of Pluto, making observations of the dwarf planet-moon system every 30-minutes," said Steve Howell, project scientist for Kepler/K2 at NASA’s Ames Research Center in Moffett Field, California. "We are excited to turn the planet-hunting Kepler spacecraft's attention to this distant solar system object to provide additional scientific insight into this far off, mysterious world, itself a miniature solar system of five moons in orbit about Pluto."

Prior to the New Horizons flyby, the SOFIA airborne observatory, an infrared telescope installed on a 747 aircraft, soared into the perfect position over the Southern Ocean on June 28, to be directly in line with Pluto and a distant star. As the dwarf planet and its atmosphere were backlit by the star, this “occultation” caused a faint shadow of Pluto to move across the surface of Earth at more than 53,000 mph, creating a ripe opportunity for SOFIA’s mobile instruments to perform scientific analysis to help scientists understand the density and structure of Pluto's atmosphere. 

"The New Horizons' and SOFIA's observations of Pluto provide a baseline measurement that will help track the evolving atmosphere of Pluto for years to come," said Pamela Marcum, SOFIA Program Scientist at NASA’s Ames Research Center. “This unique opportunity to connect what SOFIA observes remotely with in-situ measurements from New Horizons will allow future analyses of Pluto from Earth by SOFIA and other observatories to be considerably enhanced.”

Since its launch in 1990, the Hubble Space Telescope has provided the clearest Earth-orbiting telescopic views of Pluto and Charon, mapped the dwarf planet’s surface, and discovered four new moons. While monitoring Pluto in preparation for the New Horizons’ flyby, the telescope discovered the tiny moons Nix and Hydra. Kerberos and Styx were uncovered in 2011 and 2012 respectively. After analyzing several years of Hubble observations, astronomers reported this year that that the moons Nix and Hydra are tumbling chaotically along their orbits due partly to a dynamically shifting gravitational field caused by the system's two central bodies, Pluto and Charon. The moons are also football shaped, which contributes to the chaotic rotation. Hubble continues to monitor Pluto in support of the New Horizons flyby.

With the combined observations of the many missions, scientists will have a rich set of data to work with to better shed light on the shadowy dwarf planet. The data will be available to the public once it is processed.

Last Updated: July 31, 2015

Editor: Tricia Talbert

Tags:  Ames Research Center, Cassini, Dwarf Planets, Jet Propulsion Laboratory, Kepler and K2, New Horizons, Pluto, SOFIA, Solar System, Spitzer Space Telescope,

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Journey to Mars

June 20, 2015

15-134

Veteran NASA Spacecraft Nears 60,000th Lap Around Mars, No Pit Stops

Gale Crater, home to NASA's Curiosity Mars rover, shows a new face in this image made using data from the THEMIS camera on NASA's Mars Odyssey orbiter. The colors come from an image processing method that identifies mineral differences in surface materials and displays them in false colors.

Credits: NASA/JPL-Caltech/Arizona State University

Full image and caption

Seen shortly after local Martian sunrise, clouds gather in the summit pit, or caldera, of Pavonis Mons, a giant volcano on Mars, in this image from the Thermal Emission Imaging System (THEMIS) on NASA's Mars Odyssey orbiter.

Credits: NASA/JPL-Caltech/Arizona State University

Full image and caption

NASA's Mars Odyssey spacecraft will reach a major milestone June 23, when it completes its 60,000th orbit since arriving at the Red Planet in 2001.

Named after the bestselling novel “2001: A Space Odyssey” by Arthur C. Clarke, Odyssey began orbiting Mars almost 14 years ago, on Oct. 23, 2001. on Dec. 15, 2010, it became the longest-operating spacecraft ever sent to Mars, and continues to hold that record today.

Odyssey, which discovered widespread water ice just beneath the surface of the Red Planet, is still going strong today, serving as a key communications relay for NASA's Mars rovers and making continued contributions to planetary science.

“This orbital milestone is an opportunity to celebrate Odyssey’s many achievements,” said Jim Green, NASA’s director of Planetary Science. “Odyssey will continue to help lay a foundation for the first humans to Mars in the 2030s through NASA’s Journey to Mars initiative.” 

Odyssey’s orbital milestone translates into about 888 million miles (1.43 billion kilometers) traversed by the spacecraft. In addition to the 286 million miles (460 million kilometers) covered on its trip from Earth to Mars, the spacecraft is a high-mileage vehicle like no other, but remains in fine condition.

"The spacecraft is in good health, with all subsystems functional and with enough propellant for about 10 more years," said David Lehman, project manager for the Mars Odyssey at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California.

Odyssey's major discoveries began in the early months of its two-year primary mission, with gamma-ray and neutron measurements that indicated plentiful water ice just beneath the surface at high latitudes on Mars. The spacecraft's unexpectedly long service has enabled achievements such as completion of the highest-resolution global map of Mars and observation of seasonal and year-to-year changes, such as freezing and thawing of carbon dioxide.

Through its many accomplishments, the spacecraft also has aided NASA’s preparations for human missions to Mars by monitoring radiation in the environment around the planet via the Mars Radiation Environment Experiment, developed at NASA’s Johnson Space Center in Houston.

Odyssey currently is completing an adjustment to an orbit that will position it to pass over Martian terrain lit by early-morning sunlight rather than afternoon light. In its current orbit, the spacecraft always flies near each pole and along what is called the terminator. The terminator is a moving “line” that encircles Mars and passes through any point on the planet’s surface at sunrise and again at sunset, separating the portion of Mars lit by the sun from the portion experiencing darkness, dividing day and night. The position of this line varies by time of day and time of year.

"Upcoming observations will focus on what is happening in the Martian atmosphere in the morning, such as clouds, hazes and fogs, and on frosts on the surface that burn off by later in the day," said Jeffrey Plaut, Odyssey project scientist at JPL.

The planned drift to a morning-daylight orbit began in 2012, was accelerated in 2014, and will be completed with a maneuver in November to lock in the orbit timing so that each pass over the equator occurs at the same time of day.

"We have performed many orbit maneuvers over the long life of this mission, and we will use that experience conducting the one to halt the drift," said Steve Sanders, Odyssey spacecraft engineer at Lockheed Martin Space Systems in Denver.  

To date, Odyssey's Thermal Emission Imaging System (THEMIS) has yielded 208,240 images in visible-light wavelengths and 188,760 in thermal infrared wavelengths. THEMIS images are the basis for detailed global maps and identification of some surface materials, such as chloride salt deposits and silica-rich terrain. The infrared imaging also indicates how quickly regions of the surface cool at night or warm in sunlight, telling researchers how dusty or rocky the ground is.

Odyssey's three-instrument Gamma Ray Spectrometer (GRS) suite detected significant amount of hydrogen on the planet -- interpreted as water ice hidden beneath the surface. This discovery prompted NASA to send its Phoenix Mars Lander to an arctic plain on Mars in 2008, where it examined the water ice detected by Odyssey. The spectrometer suite also mapped global distribution of key chemical elements, such as iron and potassium. The University of Arizona, Tucson, headed its development. Two GRS instruments are still active: the high-energy neutron detector from the Russian Space Research Institute and the neutron spectrometer from Los Alamos National Laboratories in New Mexico.

As a communications relay for NASA's Mars rovers, Odyssey has transmitted to Earth more than 90 percent of the data received from the Opportunity rover. Future plans for Odyssey include relay duty for NASA and European Space Agency landers arriving on Mars in 2016.

Odyssey launched on April 7, 2001 from Cape Canaveral Air Force Station, Florida. JPL manages the Mars Odyssey Project for NASA's Science Mission Directorate in Washington. Lockheed Martin built the spacecraft and collaborates with JPL in mission operations. Arizona State University, Tempe, provided and operates THEMIS.

For more information about Odyssey, visit:

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

-end-

Dwayne Brown / Laurie Cantillo
Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown@nasa.gov / laura.l.cantillo@nasa.gov

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

Last Updated: July 31, 2015

Editor: Karen Northon

Tags:  Journey to Mars, Mars, Mars Odyssey, Solar System,

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MRO

April 23, 2015

Mars Orbiter Views Curiosity Rover in 'Artist's Drive'

Mars image from the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera.

Credits: NASA/JPL-Caltech/Univ. of Arizona

A view from NASA's Mars Reconnaissance Orbiter on April 8, 2015, catches sight of NASA's Curiosity Mars rover passing through a valley called "Artist's Drive" on the lower slope of Mount Sharp.

The image from the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera shows the rover's position after a drive of about 75 feet (23 meters) during the 949th Martian day, or sol, of the rover's work on Mars. 

The location of the rover, with its shadow extending toward the right, is indicated with an inscribed rectangle. North is toward the top. The view covers an area about 550 yards (500 meters) across.  An unannotated version of the image is at:

http://photojournal.jpl.nasa.gov/figures/PIA19392_fig1.jpg

Curiosity used a route through Artist's Drive on its way toward higher layers on Mount Sharp after examining exposures of the mountain's basal geological unit at "Pahrump Hills."  The rover's "Logan Pass" science destination is at the bottom left of this image. A wider map of the area is at

http://photojournal.jpl.nasa.gov/catalog/PIA19390

This image is an excerpt from HiRISE observation ESP_040770_1755. Other image products from this observation are available at:

http://hirise.lpl.arizona.edu/ESP_040770_1755

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. 

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

2015-141

Last Updated: July 31, 2015

Editor: Tony Greicius

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

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March 24, 2015

15-049

NASA's Opportunity Mars Rover Finishes Marathon, Clocks in at Just Over 11 Years

There was no tape draped across a finish line, but NASA is celebrating a win. The agency’s Mars Exploration Rover Opportunity completed its first Red Planet marathon Tuesday -- 26.219 miles (42.195 kilometers) – with a finish time of roughly 11 years and two months.

This map shows the southward path driven by Opportunity from late December 2014 until it passed marathon distance on March 24, 2015, during the 3,968th Martian day, or sol, of the rover's work on Mars.

Credits: NASA/JPL-Caltech/Univ. of Arizona

"This is the first time any human enterprise has exceeded the distance of a marathon on the surface of another world," said John Callas, Opportunity project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "A first time happens only once." 

This map shows the rover's entire traverse from landing to that point.

Credits: NASA/JPL-Caltech/MSSS/NMMNHS

The rover team at JPL plans a marathon-length relay run at the laboratory next week to celebrate.

The long-lived rover surpassed the marathon mark during a drive of 153 feet (46.5 meters). Last year, Opportunity became the long-distance champion of all off-Earth vehicles when it topped the previous record set by the former Soviet Union's Lunokhod 2 moon rover.

"This mission isn't about setting distance records, of course; it's about making scientific discoveries on Mars and inspiring future explorers to achieve even more," said Steve Squyres, Opportunity principal investigator at Cornell University in Ithaca, New York. "Still, running a marathon on Mars feels pretty cool."

Opportunity's original three-month prime mission in 2004 yielded evidence of environments with liquid water soaking the ground and flowing on planet’s surface. As the rover continued to operate far beyond expectations for its lifespan, scientists chose the rim of Endeavour Crater as a long-term destination. Since 2011, examinations of Endeavour's rim have provided information about ancient wet conditions less acidic, and more favorable for microbial life, than the environment that left clues found earlier in the mission.

JPL manages the Mars rover projects for NASA's Science Mission Directorate in Washington. The Mars Exploration Rover Project, NASA's newer Curiosity Mars rover, and three active NASA Mars orbiters are part of NASA's Mars Exploration Program, which seeks to characterize and understand Mars as a dynamic system, including its present and past environment, climate cycles, geology and biological potential. In parallel, NASA is developing the human spaceflight capabilities needed for its journey to Mars.

For more information about Opportunity, visit

http://www.nasa.gov/rovers

Follow the project on social media at:

http://twitter.com/MarsRovers

and

http://www.facebook.com/mars.rovers

-end-

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

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

Last Updated: July 31, 2015

Editor: Karen Northon

Tags:  Journey to Mars, Mars, Mars Exploration Rovers (Spirit and Opportunity), Solar System,

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