posted 06-11-2012 03:20 PM               

NASA Mars Rover Team Aims for Landing Closer to Prime Science Site

NASA has narrowed the target for its most advanced Mars rover, Curiosity, which will land on the Red Planet in August. The car-sized rover will arrive closer to its ultimate destination for science operations, but also closer to the foot of a mountain slope that poses a landing hazard.

"We're trimming the distance we'll have to drive after landing by almost half," said Pete Theisinger, Mars Science Laboratory (MSL) project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "That could get us to the mountain months earlier."

Above: This image shows changes in the target landing area for Curiosity, the rover of NASA's Mars Science Laboratory project. The larger ellipse was the target area prior to early June 2012, when the project revised it to the smaller ellipse centered nearer to the foot of Mount Sharp, inside Gale Crater.

It was possible to adjust landing plans because of increased confidence in precision landing technology aboard the MSL spacecraft, which is carrying the rover. That spacecraft can aim closer without hitting Mount Sharp at the center of Gale crater. Rock layers located in the mountain are the prime location for research with the rover.

Curiosity is scheduled to land at approximately 10:31 p.m. PDT Aug. 5 (1:31 a.m. EDT, Aug. 6). Following checkout operations, Curiosity will begin a 2-year study of whether the landing vicinity ever offered an environment favorable for microbial life.

Theisinger and other mission leaders described the target adjustment during a June 11 update to reporters Monday about preparations for landing and for operating Curiosity on Mars.

The landing target ellipse had been an ellipse approximately 12 miles wide and 16 miles long (20 kilometers by 25 kilometers). Continuing analysis of the new landing system's capabilities has allowed mission planners to shrink the area to approximately 4 miles wide and 12 miles long (7 kilometers by 20 kilometers), assuming winds and other atmospheric conditions as predicted.

Above: As of June 2012, the target landing area for NASA's Mars Science Laboratory mission is the ellipse marked on this image of Gale Crater. The ellipse is about 12 miles long and 4 miles wide (20 kilometers by 7 kilometers).

Even with the smaller ellipse, Curiosity will be able to touch down at a safe distance from steep slopes at the edge of Mount Sharp.

"We have been preparing for years for a successful landing by Curiosity, and all signs are good," said Dave Lavery, MSL program executive. "However, landing on Mars always carries risks, so success is not guaranteed. Once on the ground we'll proceed carefully. We have plenty of time since Curiosity is not as life-limited as the approximate 90-day missions like NASA’s Mars Exploration Rovers and the Phoenix lander.”

Since the spacecraft was launched in November 2011, engineers have continued testing and improving its landing software. MSL will use an upgraded version of flight software installed on its computers during the past two weeks. Additional upgrades for Mars surface operations will be sent to the rover about a week after landing.

Other preparations include upgrades to the rover's software and understanding effects of debris coming from the drill the rover will use to collect samples from rocks on Mars. Experiments at JPL indicate that Teflon from the drill could mix with the powdered samples. Testing will continue past landing with copies of the drill. The rover will deliver the samples to onboard instruments that can identify mineral and chemical ingredients.

"The material from the drill could complicate, but will not prevent analysis of carbon content in rocks by one of the rover's 10 instruments. There are workarounds," said John Grotzinger, MSL project scientist at the California Institute of Technology in Pasadena. "Organic carbon compounds in an environment are one prerequisite for life. We know meteorites deliver non-biological organic carbon to Mars, but not whether it persists near the surface. We will be checking for that and for other chemical and mineral clues about habitability."

Curiosity will be in good company as it nears landing. Two NASA Mars orbiters along with a European Space Agency orbiter will be in position to listen to radio transmissions as MSL descends through Mars' atmosphere.

posted 07-16-2012 01:11 PM               

NASA's car-sized rover nears landing on Mars

NASA's most advanced planetary rover is on a precise course for an early August landing beside a Martian mountain to begin two years of unprecedented scientific detective work. However, getting the Curiosity rover to the surface of Mars will not be easy.

"The Curiosity landing is the hardest NASA mission ever attempted in the history of robotic planetary exploration," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate, at NASA Headquarters in Washington. "While the challenge is great, the team's skill and determination give me high confidence in a successful landing."

The Mars Science Laboratory (MSL) mission is a precursor mission for future human mission to Mars. President Obama has set a challenge to reach the Red Planet in the 2030s.

To achieve the precision needed for landing safely inside Gale Crater, the spacecraft will fly like a wing in the upper atmosphere instead of dropping like a rock. To land the 1-ton rover, an air-bag method used on previous Mars rovers will not work. Mission engineers at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., designed a "sky crane" method for the final several seconds of the flight. A backpack with retro-rockets controlling descent speed will lower the rover on three nylon cords just before touchdown.

During a critical period lasting only about seven minutes, the MSL spacecraft carrying Curiosity must decelerate from about 13,200 mph (about 5,900 meters per second) to allow the rover to land on the surface at about 1.7 mph (three-fourths of a meter per second). Curiosity is scheduled to land at approximately 1:31 a.m. EDT Aug. 6 (10:31 p.m. PDT Aug. 5).

"Those seven minutes are the most challenging part of this entire mission," said Pete Theisinger, JPL's MSL project manager. "For the landing to succeed, hundreds of events will need to go right, many with split-second timing and all controlled autonomously by the spacecraft. We've done all we can think of to succeed. We expect to get Curiosity safely onto the ground, but there is no guarantee. The risks are real."

During the initial weeks after the actual landing, JPL mission controllers will put the rover through a series of checkouts and activities to characterize its performance on Mars while gradually ramping up scientific investigations. Curiosity then will begin investigating whether an area with a wet history inside Mars' Gale Crater ever has offered an environment favorable for microbial life.

"Earlier missions have found that ancient Mars had wet environments," said Michael Meyer, lead scientist for NASA's Mars Program at NASA Headquarters. "Curiosity takes us the next logical step in understanding the potential for life on Mars."

Curiosity will use tools on a robotic arm to deliver samples from Martian rocks and soils into laboratory instruments inside the rover that can reveal chemical and mineral composition. A laser instrument will use its beam to induce a spark on a target and read the spark's spectrum of light to identify chemical elements in the target.

Other instruments on the car-sized rover will examine the surrounding environment from a distance or by direct touch with the arm. The rover will check for the basic chemical ingredients for life and for evidence about energy available for life. It also will assess factors that could be hazardous for life, such as the radiation environment.

"For its ambitious goals, this mission needs a great landing site and a big payload," said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters. "During the descent through the atmosphere, the mission will rely on bold techniques enabling use of a smaller target area and a heavier robot on the ground than were possible for any previous Mars mission. Those techniques also advance us toward human-crew Mars missions, which will need even more precise targeting and heavier landers."

The chosen landing site is beside a mountain informally called Mount Sharp. The mission's prime destination lies on the slope of the mountain. Driving there from the landing site may take many months.

"Be patient about the drive. It will be well worth the wait and we are apt to find some targets of interest on the way," said John Grotzinger, MSL project scientist at the California Institute of Technology in Pasadena. "When we get to the lower layers in Mount Sharp, we'll read them like chapters in a book about changing environmental conditions when Mars was wetter than it is today."

posted 07-24-2012 07:20 PM               

NASA Mars orbiter repositioned to phone home Mars landing

NASA's Mars Odyssey spacecraft has successfully adjusted its orbital location to be in a better position to provide prompt confirmation of the August landing of the Curiosity rover.

The Mars Science Laboratory carrying Curiosity can send limited information directly to Earth as it enters Mars' atmosphere. Before the landing, Earth will set below the Martian horizon from the descending spacecraft's perspective, ending that direct route of communication. Odyssey will help to speed up the indirect communication process.

NASA reported on July 16 that Odyssey, which originally was planned to provide a near-real-time communication link with Curiosity, had entered safe mode July 11. This would have affected communication operations, but not the rover's landing. Without a repositioning maneuver, Odyssey would have arrived over the landing area about two minutes after Curiosity landed.

A spacecraft thruster burn Tuesday lasting about six seconds has nudged Odyssey about six minutes ahead in its orbit. Odyssey now is operating normally, and confirmation of Curiosity's landing is expected to reach Earth at about 10:31 p.m. PDT Aug. 5, as originally planned.

"Information we are receiving indicates the maneuver has been completed as planned," said Gaylon McSmith, Mars Odyssey project manager at NASA's Jet Propulsion Laboratory (JPL), in Pasadena, Calif. "Odyssey has been working at Mars longer than any other spacecraft, so it is appropriate that it has a special role in supporting the newest arrival."

Two other Mars orbiters, NASA's Mars Reconnaissance Orbiter and the European Space Agency's Mars Express, also will be in position to receive radio transmissions from MSL during its descent. However, they will be recording information for later playback. Only Odyssey can relay information immediately.

Odyssey arrived at Mars in 2001. In addition to its own scientific observations, it has served as a communications relay for NASA's Spirit and Opportunity Mars rovers and the Phoenix lander. Spirit and Phoenix are no longer operational. Odyssey and MRO will provide communication relays for Curiosity during the rover's two-year prime mission.

posted 08-01-2012 06:31 AM               

Entry, descent and landing timeline activated

The Mars Science Laboratory (MSL) continues its final preparations for entry, descent and landing this upcoming weekend.

On July 30, the flight team completed and confirmed a memory test on the software for the mechanical assembly that controls MSL's descent motor. They also configured the spacecraft for its transition to entry, descent and landing approach mode, and they enabled the spacecraft's hardware pyrotechnic devices.

MSL is now under the control of the autonomous entry, descent and landing timeline flight software. The flight team continues to monitor Curiosity's onboard systems and flight trajectory. The spacecraft and ground systems remain in good health, with no significant issues being worked.

posted 08-03-2012 06:51 PM               

Entry, descent and landing...

For updates through the entry, descent and landing at Gale Crater, see the collectSPACE Special Report: Curiosity: Mars Science Laboratory with live reporting from NASA's Jet Propulsion Laboratory.

posted 08-06-2012 01:22 AM               

NASA's Curiosity lands on Mars: Car-sized rover to seek signs of life-friendly land

NASA has a new six-wheeled science lab on Mars.

The car-size Curiosity rover touched down safely on the Red Planet at 1:17:57 a.m. EDT (0517 GMT) on Monday (Aug. 6), after eight months cruising from Earth to Mars. Leading up to the landing was a 7-minute automated entry and descent through the planet's atmosphere that relied on thrusters, a supersonic parachute, eight retrorockets and a "sky crane" to deposit the nearly one-ton, nuclear-powered rover at Gale Crater.

posted 08-22-2012 04:21 PM               

NASA's Mars rover Curiosity leaves coded tracks on first test drive

NASA's Curiosity Mars rover has left its first tracks in the Martian soil, leaving the coded mark of its maker in its trail.

On Wednesday (Aug. 22), the car-size, six-wheeled rover took its first test drive since arriving on the Red Planet more than two weeks ago. Its drivers on Earth ordered Curiosity to roll forward about 15 feet, (4.5 meters), turn right and then back up about 8 feet (2.5 meters), such that when it stopped it was positioned to the left and roughly perpendicular to where it touched down inside Mars' Gale Crater.

"You can see in the tracks how we drive forward, and then you can see roughly a circle, which is where the rover did what we call its turn in place maneuver," said lead rover planner Matt Heverly of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "So it steered all of its wheels and then performed a turn of a 120 degrees, pivoting about a point in the center of that circle, and then it backed up."

Curiosity's path to its new parking spot was emblazoned on the Martian surface by a series of dash and dot tread marks that were left in the soil by each of the rover's 20-inch diameter (50 centimeter) wheels...

posted 12-03-2012 11:16 AM               

NASA Mars rover fully analyzes first martian soil samples

NASA's Mars Curiosity rover has used its full array of instruments to analyze Martian soil for the first time, and found a complex chemistry within the Martian soil. Water and sulfur and chlorine-containing substances, among other ingredients, showed up in samples that Curiosity's arm delivered to an analytical laboratory inside the rover.

Above: A view of the third (left) and fourth (right) trenches made by the 1.6-inch-wide (4-centimeter-wide) scoop on NASA's Mars rover Curiosity in October 2012.

Detection of the substances during this early phase of the mission demonstrates the laboratory's capability to analyze diverse soil and rock samples over the next two years. Scientists also have been verifying the capabilities of the rover's instruments.

Curiosity is the first Mars rover able to scoop soil into analytical instruments. The specific soil sample came from a drift of windblown dust and sand called "Rocknest." The site lies in a relatively flat part of Gale Crater still miles away from the rover's main destination on the slope of a mountain called Mount Sharp. The rover's laboratory includes the Sample Analysis at Mars (SAM) suite and the Chemistry and Mineralogy (CheMin) instrument. SAM used three methods to analyze gases given off from the dusty sand when it was heated in a tiny oven. One class of substances SAM checks for is organic compounds — carbon-containing chemicals that can be ingredients for life.

"We have no definitive detection of Martian organics at this point, but we will keep looking in the diverse environments of Gale Crater," said SAM Principal Investigator Paul Mahaffy of NASA's Goddard Space Flight Center in Greenbelt, Md.

Curiosity's APXS instrument and the Mars Hand Lens Imager (MAHLI) camera on the rover's arm confirmed Rocknest has chemical-element composition and textural appearance similar to sites visited by earlier NASA Mars rovers Pathfinder, Spirit and Opportunity.

Curiosity's team selected Rocknest as the first scooping site because it has fine sand particles suited for scrubbing interior surfaces of the arm's sample-handling chambers. Sand was vibrated inside the chambers to remove residue from Earth. MAHLI close-up images of Rocknest show a dust-coated crust one or two sand grains thick, covering dark, finer sand.

"Active drifts on Mars look darker on the surface," said MAHLI Principal Investigator Ken Edgett, of Malin Space Science Systems in San Diego."This is an older drift that has had time to be inactive, letting the crust form and dust accumulate on it."

CheMin's examination of Rocknest samples found the composition is about half common volcanic minerals and half non-crystalline materials such as glass. SAM added information about ingredients present in much lower concentrations and about ratios of isotopes. Isotopes are different forms of the same element and can provide clues about environmental changes. The water seen by SAM does not mean the drift was wet. Water molecules bound to grains of sand or dust are not unusual, but the quantity seen was higher than anticipated.

SAM tentatively identified the oxygen and chlorine compound perchlorate. This is a reactive chemical previously found in arctic Martian soil by NASA's Phoenix Lander. Reactions with other chemicals heated in SAM formed chlorinated methane compounds — one-carbon organics that were detected by the instrument. The chlorine is of Martian origin, but it is possible the carbon may be of Earth origin, carried by Curiosity and detected by SAM's high sensitivity design.

"We used almost every part of our science payload examining this drift," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. "The synergies of the instruments and richness of the data sets give us great promise for using them at the mission's main science destination on Mount Sharp."

posted 02-09-2013 02:18 PM               

NASA Curiosity rover collects first Martian bedrock sample

NASA's Curiosity rover has, for the first time, used a drill carried at the end of its robotic arm to bore into a flat, veiny rock on Mars and collect a sample from its interior. This is the first time any robot has drilled into a rock to collect a sample on Mars.

Above: An animated set of three images from NASA's Curiosity rover shows the rover's drill in action on Feb. 8, 2013, or Sol 182, Curiosity's 182nd Martian day of operations. This was the first use of the drill for rock sample collection. The target was a rock called "John Klein," in the Yellowknife Bay region of Gale Crater on Mars.

The fresh hole, about 0.63 inch (1.6 centimeters) wide and 2.5 inches (6.4 centimeters) deep in a patch of fine-grained sedimentary bedrock, can be seen in images and other data Curiosity beamed to Earth Saturday. The rock is believed to hold evidence about long-gone wet environments. In pursuit of that evidence, the rover will use its laboratory instruments to analyze rock powder collected by the drill.

"The most advanced planetary robot ever designed now is a fully operating analytical laboratory on Mars," said John Grunsfeld, NASA associate administrator for the agency's Science Mission Directorate. "This is the biggest milestone accomplishment for the Curiosity team since the sky-crane landing last August, another proud day for America."

For the next several days, ground controllers will command the rover's arm to carry out a series of steps to process the sample, ultimately delivering portions to the instruments inside.

"We commanded the first full-depth drilling, and we believe we have collected sufficient material from the rock to meet our objectives of hardware cleaning and sample drop-off," said Avi Okon, drill cognizant engineer at NASA's Jet Propulsion Laboratory (JPL), Pasadena.

Rock powder generated during drilling travels up flutes on the bit. The bit assembly has chambers to hold the powder until it can be transferred to the sample-handling mechanisms of the rover's Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) device.

Before the rock powder is analyzed, some will be used to scour traces of material that may have been deposited onto the hardware while the rover still was on Earth, despite thorough cleaning before launch.

"We'll take the powder we acquired and swish it around to scrub the internal surfaces of the drill bit assembly," said JPL's Scott McCloskey, drill systems engineer. "Then we'll use the arm to transfer the powder out of the drill into the scoop, which will be our first chance to see the acquired sample."

"Building a tool to interact forcefully with unpredictable rocks on Mars required an ambitious development and testing program," said JPL's Louise Jandura, chief engineer for Curiosity's sample system."To get to the point of making this hole in a rock on Mars, we made eight drills and bored more than 1,200 holes in 20 types of rock on Earth."

Inside the sample-handling device, the powder will be vibrated once or twice over a sieve that screens out any particles larger than six-thousandths of an inch (150 microns) across. Small portions of the sieved sample will fall through ports on the rover deck into the Chemistry and Mineralogy (CheMin) instrument and the Sample Analysis at Mars (SAM) instrument. These instruments then will begin the much-anticipated detailed analysis.

The rock Curiosity drilled is called "John Klein" in memory of a Mars Science Laboratory deputy project manager who died in 2011. Drilling for a sample is the last new activity for NASA's Mars Science Laboratory Project, which is using the car-size Curiosity rover to investigate whether an area within Mars' Gale Crater has ever offered an environment favorable for life.

posted 02-21-2013 07:36 AM               

NASA Mars rover confirms first drilled Martian rock sample

NASA's Mars rover Curiosity has relayed new images that confirm it has successfully obtained the first sample ever collected from the interior of a rock on another planet. No rover has ever drilled into a rock beyond Earth and collected a sample from its interior.

Transfer of the powdered-rock sample into an open scoop was visible for the first time in images received Wednesday at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

"Seeing the powder from the drill in the scoop allows us to verify for the first time the drill collected a sample as it bore into the rock," said JPL's Scott McCloskey, drill systems engineer for Curiosity. "Many of us have been working toward this day for years. Getting final confirmation of successful drilling is incredibly gratifying. For the sampling team, this is the equivalent of the landing team going crazy after the successful touchdown."

The drill on Curiosity's robotic arm took in the powder as it bored a 2.5-inch (6.4-centimeter) hole into a target on flat Martian bedrock on Feb. 8. The rover team plans to have Curiosity sieve the sample and deliver portions of it to analytical instruments inside the rover.

The scoop now holding the precious sample is part of Curiosity's Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) device. During the next steps of processing, the powder will be enclosed inside CHIMRA and shaken once or twice over a sieve that screens out particles larger than 0.006 inch (150 microns) across.

Small portions of the sieved sample later will be delivered through inlet ports on top of the rover deck into the Chemistry and Mineralogy (CheMin) instrument and Sample Analysis at Mars (SAM) instrument.

In response to information gained during testing at JPL, the processing and delivery plan has been adjusted to reduce use of mechanical vibration. The 150-micron screen in one of the two test versions of CHIMRA became partially detached after extensive use, although it remained usable. The team has added precautions for use of Curiosity's sampling system while continuing to study the cause and ramifications of the separation.

The sample comes from a fine-grained, veiny sedimentary rock called "John Klein," named in memory of a Mars Science Laboratory deputy project manager who died in 2011. The rock was selected for the first sample drilling because it may hold evidence of wet environmental conditions long ago. The rover's laboratory analysis of the powder may provide information about those conditions.

posted 03-02-2013 02:02 PM               

Computer Swap on Curiosity Rover

The ground team for NASA's Mars rover Curiosity has switched the rover to a redundant onboard computer in response to a memory issue on the computer that had been active.

The intentional swap at about 2:30 a.m. PST today (Thursday, Feb. 28) put the rover, as anticipated, into a minimal-activity precautionary status called "safe mode." The team is shifting the rover from safe mode to operational status over the next few days and is troubleshooting the condition that affected operations yesterday. The condition is related to a glitch in flash memory linked to the other, now-inactive, computer.

"We switched computers to get to a standard state from which to begin restoring routine operations," said Richard Cook of NASA's Jet Propulsion Laboratory, project manager for the Mars Science Laboratory Project, which built and operates Curiosity.

Like many spacecraft, Curiosity carries a pair of redundant main computers in order to have a backup available if one fails. Each of the computers, A-side and B-side, also has other redundant subsystems linked to just that computer. Curiosity is now operating on its B-side, as it did during part of the flight from Earth to Mars. It operated on its A-side from before the August 2012 landing through Wednesday.

"While we are resuming operations on the B-side, we are also working to determine the best way to restore the A-side as a viable backup," said JPL engineer Magdy Bareh, leader of the mission's anomaly resolution team.

The spacecraft remained in communications at all scheduled communication windows on Wednesday, but it did not send recorded data, only current status information. The status information revealed that the computer had not switched to the usual daily "sleep" mode when planned. Diagnostic work in a testing simulation at JPL indicates the situation involved corrupted memory at an A-side memory location used for addressing memory files.

Scientific investigations by the rover were suspended Wednesday and today. Resumption of science investigations is anticipated within several days. This week, laboratory instruments inside the rover have been analyzing portions of the first sample of rock powder ever collected from the interior of a rock on Mars.

posted 03-12-2013 12:38 PM               

NASA Rover Finds Conditions Once Suited for Ancient Life on Mars

An analysis of a rock sample collected by NASA's Curiosity rover shows ancient Mars could have supported living microbes.

Scientists identified sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon -- some of the key chemical ingredients for life -- in the powder Curiosity drilled out of a sedimentary rock near an ancient stream bed in Gale Crater on the Red Planet last month.

"A fundamental question for this mission is whether Mars could have supported a habitable environment," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "From what we know now, the answer is yes."

Clues to this habitable environment come from data returned by the rover's Sample Analysis at Mars (SAM) and Chemistry and Mineralogy (CheMin) instruments. The data indicate the Yellowknife Bay area the rover is exploring was the end of an ancient river system or an intermittently wet lake bed that could have provided chemical energy and other favorable conditions for microbes. The rock is made up of a fine-grained mudstone containing clay minerals, sulfate minerals and other chemicals. This ancient wet environment, unlike some others on Mars, was not harshly oxidizing, acidic or extremely salty.

The patch of bedrock where Curiosity drilled for its first sample lies in an ancient network of stream channels descending from the rim of Gale Crater. The bedrock also is fine-grained mudstone and shows evidence of multiple periods of wet conditions, including nodules and veins.

Curiosity's drill collected the sample at a site just a few hundred yards away from where the rover earlier found an ancient streambed in September 2012.

"Clay minerals make up at least 20 percent of the composition of this sample," said David Blake, principal investigator for the CheMin instrument at NASA's Ames Research Center in Moffett Field, Calif.

These clay minerals are a product of the reaction of relatively fresh water with igneous minerals, such as olivine, also present in the sediment. The reaction could have taken place within the sedimentary deposit, during transport of the sediment, or in the source region of the sediment. The presence of calcium sulfate along with the clay suggests the soil is neutral or mildly alkaline.

Scientists were surprised to find a mixture of oxidized, less-oxidized, and even non-oxidized chemicals, providing an energy gradient of the sort many microbes on Earth exploit to live. This partial oxidation was first hinted at when the drill cuttings were revealed to be gray rather than red.

"The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms," said Paul Mahaffy, principal investigator of the SAM suite of instruments at NASA's Goddard Space Flight Center in Greenbelt, Md.

An additional drilled sample will be used to help confirm these results for several of the trace gases analyzed by the SAM instrument.

"We have characterized a very ancient, but strangely new 'gray Mars' where conditions once were favorable for life," said John Grotzinger, Mars Science Laboratory project scientist at the California Institute of Technology in Pasadena, Calif. "Curiosity is on a mission of discovery and exploration, and as a team we feel there are many more exciting discoveries ahead of us in the months and years to come."

Scientists plan to work with Curiosity in the "Yellowknife Bay" area for many more weeks before beginning a long drive to Gale Crater's central mound, Mount Sharp. Investigating the stack of layers exposed on Mount Sharp, where clay minerals and sulfate minerals have been identified from orbit, may add information about the duration and diversity of habitable conditions.

posted 03-20-2013 09:11 AM               

Curiosity Rover Exits 'Safe Mode'

NASA's Mars rover Curiosity has returned to active status and is on track to resume science investigations, following two days in a precautionary standby status, "safe mode."

Next steps will include checking the rover's active computer, the B-side computer, by commanding a preliminary free-space move of the arm. The B-side computer was provided information last week about the position of the robotic arm, which was last moved by the redundant A-side computer.

The rover was switched from the A-side to the B-side by engineers on Feb. 28 in response to a memory glitch on the A-side. The A-side now is available as a back-up if needed.

"We expect to get back to sample-analysis science by the end of the week," said Curiosity Mission Manager Jennifer Trosper of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Engineers quickly diagnosed the software issue that prompted the safe mode on March 16 and know how to prevent it from happening again.

Other upcoming activities include preparations for a moratorium on transmitting commands to Curiosity during most of April, when Mars will be passing nearly directly behind the sun from Earth's perspective. The moratorium is a precaution against interference by the sun corrupting a command sent to the rover.

posted 04-03-2013 02:26 PM               

Used Parachute on Mars Flaps in the Wind

Photos from NASA's Mars Reconnaissance Orbiter show how the parachute that helped NASA's Curiosity rover land on Mars last summer has subsequently changed its shape on the ground.

The images were obtained by the High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter.

Seven images taken by HiRISE between Aug. 12, 2012, and Jan. 13, 2013, show the used parachute shifting its shape at least twice in response to wind.

Researchers have used HiRISE to study many types of changes on Mars. Its first image of Curiosity's parachute, not included in this series, caught the spacecraft suspended from the chute during descent through the Martian atmosphere.

posted 06-05-2013 03:33 PM               

NASA's Curiosity Mars Rover Nears Turning Point

NASA's Mars Science Laboratory mission is approaching its biggest turning point since landing its rover, Curiosity, inside Mars' Gale Crater last summer.

Curiosity is finishing investigations in an area smaller than a football field where it has been working for six months, and it will soon shift to a distance-driving mode headed for an area about 5 miles (8 kilometers) away, at the base Mount Sharp.

In May, the mission drilled a second rock target for sample material and delivered portions of that rock powder into laboratory instruments in one week, about one-fourth as much time as needed at the first drilled rock.

"We're hitting full stride," said Mars Science Laboratory Project Manager Jim Erickson of NASA's Jet Propulsion Laboratory, Pasadena, Calif. "We needed a more deliberate pace for all the first-time activities by Curiosity since landing, but we won't have many more of those."

No additional rock drilling or soil scooping is planned in the "Glenelg" area that Curiosity entered last fall as the mission's first destination after landing. To reach Glenelg, the rover drove east about a third of a mile (500 meters) from the landing site. To reach the next destination, Mount Sharp, Curiosity will drive toward the southwest for many months.

"We don't know when we'll get to Mount Sharp," Erickson said. "This truly is a mission of exploration, so just because our end goal is Mount Sharp doesn't mean we're not going to investigate interesting features along the way."

Images of Mount Sharp taken from orbit and images Curiosity has taken from a distance reveal many layers where scientists anticipate finding evidence about how the ancient Martian environment changed and evolved.

While completing major first-time activities since landing, the mission has also already accomplished its main science objective. Analysis of rock powder from the first drilled rock target, "John Klein," provided evidence that an ancient environment in Gale Crater had favorable conditions for microbial life: the essential elemental ingredients, energy and ponded water that was neither too acidic nor too briny.

The rover team chose a similar rock, "Cumberland," as the second drilling target to provide a check for the findings at John Klein. Scientists are analyzing laboratory-instrument results from portions of the Cumberland sample. One new capability being used is to drive away while still holding rock powder in Curiosity's sample-handling device to supply additional material to instruments later if desired by the science team.

For the drill campaign at Cumberland, steps that each took a day or more at John Klein could be combined into a single day's sequence of commands. "We used the experience and lessons from our first drilling campaign, as well as new cached sample capabilities, to do the second drill campaign far more efficiently," said sampling activity lead Joe Melko of JPL. "In addition, we increased use of the rover's autonomous self-protection. This allowed more activities to be strung together before the ground team had to check in on the rover."

The science team has chosen three targets for brief observations before Curiosity leaves the Glenelg area: the boundary between bedrock areas of mudstone and sandstone, a layered outcrop called "Shaler" and a pitted outcrop called "Point Lake."

JPL's Joy Crisp, deputy project scientist for Curiosity, said "Shaler might be a river deposit. Point Lake might be volcanic or sedimentary. A closer look at them could give us better understanding of how the rocks we sampled with the drill fit into the history of how the environment changed."

posted 08-02-2013 07:29 AM               

Twelve Months in Two Minutes; Curiosity's First Year on Mars

Here is a rover's eye view of driving, scooping and drilling during Curiosity's first year on Mars, August 2012 through July 2013.

posted 09-20-2013 08:19 AM               

NASA Curiosity Rover Detects No Methane on Mars

Data from NASA's Curiosity rover has revealed the Martian environment lacks methane. This is a surprise to researchers because previous data reported by U.S. and international scientists indicated positive detections.

The roving laboratory performed extensive tests to search for traces of Martian methane. Whether the Martian atmosphere contains traces of the gas has been a question of high interest for years because methane could be a potential sign of life, although it also can be produced without biology.

"This important result will help direct our efforts to examine the possibility of life on Mars," said Michael Meyer, NASA's lead scientist for Mars exploration. "It reduces the probability of current methane-producing Martian microbes, but this addresses only one type of microbial metabolism. As we know, there are many types of terrestrial microbes that don't generate methane."

Curiosity analyzed samples of the Martian atmosphere for methane six times from October 2012 through June and detected none. Given the sensitivity of the instrument used, the Tunable Laser Spectrometer, and not detecting the gas, scientists calculate the amount of methane in the Martian atmosphere today must be no more than 1.3 parts per billion, which is about one-sixth as much as some earlier estimates. Details of the findings appear in the Thursday edition of Science Express.

"It would have been exciting to find methane, but we have high confidence in our measurements, and the progress in expanding knowledge is what's really important," said the report's lead author, Chris Webster of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "We measured repeatedly from Martian spring to late summer, but with no detection of methane."

Webster is the lead scientist for spectrometer, which is part of Curiosity's Sample Analysis at Mars (SAM) laboratory. It can be tuned specifically for detection of trace methane. The laboratory also can concentrate any methane to increase the gas' ability to be detected. The rover team will use this method to check for methane at concentrations well below 1 part per billion.

Methane, the most abundant hydrocarbon in our solar system, has one carbon atom bound to four hydrogen atoms in each molecule. Previous reports of localized methane concentrations up to 45 parts per billion on Mars, which sparked interest in the possibility of a biological source on Mars, were based on observations from Earth and from orbit around Mars. However, the measurements from Curiosity are not consistent with such concentrations, even if the methane had dispersed globally.

"There's no known way for methane to disappear quickly from the atmosphere," said one of the paper's co-authors, Sushil Atreya of the University of Michigan. "Methane is persistent. It would last for hundreds of years in the Martian atmosphere. Without a way to take it out of the atmosphere quicker, our measurements indicate there cannot be much methane being put into the atmosphere by any mechanism, whether biology, geology, or by ultraviolet degradation of organics delivered by the fall of meteorites or interplanetary dust particles."

The highest concentration of methane that could be present without being detected by Curiosity's measurements so far would amount to no more than 10 to 20 tons per year of methane entering the Martian atmosphere, Atreya estimated. That is about 50 million times less than the rate of methane entering Earth's atmosphere.

posted 01-10-2014 02:38 PM               

Mars orbiter images rover, tracks in Gale Crater

NASA's Curiosity Mars rover and its recent tracks from driving in Gale Crater appear in an image taken by the High Resolution Imaging Science Experiment camera on NASA's Mars Reconnaissance Orbiter on Dec. 11, 2013.

Excerpts from the large HiRISE observation show the rover and tracks across a landscape in enhanced color.

The tracks show where the rover has zigzagged around obstacles on its route toward the lower slopes of Mount Sharp, its next major destination.

HiRISE first imaged the Mars Science Laboratory spacecraft while it was descending on a parachute to place Curiosity on Mars 17 months ago. Since then, it has provided updated views of the rover's traverse, as seen from orbit.

posted 06-24-2014 05:53 AM               

NASA's Mars Curiosity Rover Marks First Martian Year

NASA's Mars Curiosity rover will complete a Martian year — 687 Earth days — on June 24, having accomplished the mission's main goal of determining whether Mars once offered environmental conditions favorable for microbial life.

One of Curiosity's first major findings after landing on the Red Planet in August 2012 was an ancient riverbed at its landing site. Nearby, at an area known as Yellowknife Bay, the mission met its main goal of determining whether the Martian Gale Crater ever was habitable for simple life forms. The answer, a historic "yes," came from two mudstone slabs that the rover sampled with its drill. Analysis of these samples revealed the site was once a lakebed with mild water, the essential elemental ingredients for life, and a type of chemical energy source used by some microbes on Earth. If Mars had living organisms, this would have been a good home for them.

Above: NASA's Curiosity Mars rover used the camera at the end of its arm in April and May 2014 to take dozens of component images combined into this self-portrait where the rover drilled into a sandstone target called "Windjana." Credit: NASA/JPL-Caltech/MSSS

Other important findings during the first Martian year include:

• Assessing natural radiation levels both during the flight to Mars and on the Martian surface provides guidance for designing the protection needed for human missions to Mars.

• Measurements of heavy-versus-light variants of elements in the Martian atmosphere indicate that much of Mars' early atmosphere disappeared by processes favoring loss of lighter atoms, such as from the top of the atmosphere. Other measurements found that the atmosphere holds very little, if any, methane, a gas that can be produced biologically.

• The first determinations of the age of a rock on Mars and how long a rock has been exposed to harmful radiation provide prospects for learning when water flowed and for assessing degradation rates of organic compounds in rocks and soils.

Curiosity paused in driving this spring to drill and collect a sample from a sandstone site called Windjana. The rover currently is carrying some of the rock-powder sample collected at the site for follow-up analysis.

"Windjana has more magnetite than previous samples we've analyzed," said David Blake, principal investigator for Curiosity's Chemistry and Mineralogy (CheMin) instrument at NASA's Ames Research Center, Moffett Field, California. "A key question is whether this magnetite is a component of the original basalt or resulted from later processes, such as would happen in water-soaked basaltic sediments. The answer is important to our understanding of habitability and the nature of the early-Mars environment."

Preliminary indications are that the rock contains a more diverse mix of clay minerals than was found in the mission's only previously drilled rocks, the mudstone targets at Yellowknife Bay. Windjana also contains an unexpectedly high amount of the mineral orthoclase, a potassium-rich feldspar that is one of the most abundant minerals in Earth's crust that had never before been definitively detected on Mars.

This finding implies that some rocks on the Gale Crater rim, from which the Windjana sandstones are thought to have been derived, may have experienced complex geological processing, such as multiple episodes of melting.

"It's too early for conclusions, but we expect the results to help us connect what we learned at Yellowknife Bay to what we'll learn at Mount Sharp," said John Grotzinger, Curiosity project scientist at the California Institute of Technology, Pasadena. "Windjana is still within an area where a river flowed. We see signs of a complex history of interaction between water and rock."

Curiosity departed Windjana in mid-May and is advancing westward. It has covered about nine-tenths of a mile (1.5 kilometers) in 23 driving days and brought the mission's odometer tally up to 4.9 miles (7.9 kilometers).

Since wheel damage prompted a slow-down in driving late in 2013, the mission team has adjusted routes and driving methods to reduce the rate of damage.

For example, the mission team revised the planned route to future destinations on the lower slope of an area called Mount Sharp, where scientists expect geological layering will yield answers about ancient environments. Before Curiosity landed, scientists anticipated that the rover would need to reach Mount Sharp to meet the goal of determining whether the ancient environment was favorable for life. They found an answer much closer to the landing site. The findings so far have raised the bar for the work ahead. At Mount Sharp, the mission team will seek evidence not only of habitability, but also of how environments evolved and what conditions favored preservation of clues to whether life existed there.

The entry gate to the mountain is a gap in a band of dunes edging the mountain's northern flank that is approximately 2.4 miles (3.9 kilometers) ahead of the rover's current location. The new path will take Curiosity across sandy patches as well as rockier ground. Terrain mapping with use of imaging from NASA's Mars Reconnaissance Orbiter enables the charting of safer, though longer, routes.

The team expects it will need to continually adapt to the threats posed by the terrain to the rover's wheels but does not expect this will be a determining factor in the length of Curiosity's operational life.

"We are getting in some long drives using what we have learned," said Jim Erickson, Curiosity project manager at NASA's Jet Propulsion Laboratory in Pasadena, California. "When you're exploring another planet, you expect surprises. The sharp, embedded rocks were a bad surprise. Yellowknife Bay was a good surprise."

posted 08-06-2014 06:50 AM               

NASA Mars Curiosity Rover: Two Years and Counting on Red Planet

NASA's most advanced roving laboratory on Mars celebrates its second anniversary since landing inside the Red Planet's Gale Crater on Aug. 5, 2012, PDT (Aug. 6, 2012, EDT).

During its first year of operations, the Curiosity rover fulfilled its major science goal of determining whether Mars ever offered environmental conditions favorable for microbial life. Clay-bearing sedimentary rocks on the crater floor in an area called Yellowknife Bay yielded evidence of a lakebed environment billions of years ago that offered fresh water, all of the key elemental ingredients for life, and a chemical source of energy for microbes, if any existed there.

"Before landing, we expected that we would need to drive much farther before answering that habitability question," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology, Pasadena. "We were able to take advantage of landing very close to an ancient streambed and lake. Now we want to learn more about how environmental conditions on Mars evolved, and we know where to go to do that."

During its second year, Curiosity has been driving toward long-term science destinations on lower slopes of Mount Sharp. Those destinations are in an area beginning about 2 miles (3 kilometers) southwest of the rover's current location, but an appetizer outcrop of a base layer of the mountain lies much closer -- less than one-third of a mile (500 meters) from Curiosity. The rover team is calling the outcrop "Pahrump Hills."

For about half of July, the rover team at NASA's Jet Propulsion Laboratory in Pasadena, California, drove Curiosity across an area of hazardous sharp rocks on Mars called "Zabriskie Plateau." Damage to Curiosity's aluminum wheels from driving across similar terrain last year prompted a change in route, with the plan of skirting such rock-studded terrain wherever feasible. The one-eighth mile (200 meters) across Zabriskie Plateau was one of the longest stretches without a suitable detour on the redesigned route toward the long-term science destination.

Another recent challenge appeared last week in the form of unexpected behavior by an onboard computer currently serving as backup. Curiosity carries duplicate main computers. It has been operating on its B-side computer since a problem with the A-side computer prompted the team to command a side swap in February 2013. Work in subsequent weeks of 2013 restored availability of the A-side as a backup in case of B-side trouble. In July, fresh commanding of the rover was suspended for two days while engineers confirmed that the A-side computer remains reliable as a backup.

To help prepare for future human missions to Mars, Curiosity incudes a radiation detector to measure the environment astronauts will encounter on a round-trip between Earth and the Martian surface. The data are consistent with earlier predictions and will help NASA scientists and engineers develop new technologies to protect astronauts in deep space.

posted 09-11-2014 01:02 PM               

NASA's Mars Curiosity Rover Arrives at Martian Mountain

NASA's Mars Curiosity rover has reached the Red Planet's Mount Sharp, a Mount-Rainier-size mountain at the center of the vast Gale Crater and the rover mission's long-term prime destination.

"Curiosity now will begin a new chapter from an already outstanding introduction to the world," said Jim Green, director of NASA's Planetary Science Division at NASA Headquarters in Washington. "After a historic and innovative landing along with its successful science discoveries, the scientific sequel is upon us."

Curiosity's trek up the mountain will begin with an examination of the mountain's lower slopes. The rover is starting this process at an entry point near an outcrop called Pahrump Hills, rather than continuing on to the previously-planned, further entry point known as Murray Buttes. Both entry points lay along a boundary where the southern base layer of the mountain meets crater-floor deposits washed down from the crater's northern rim.

"It has been a long but historic journey to this Martian mountain," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena. "The nature of the terrain at Pahrump Hills and just beyond it is a better place than Murray Buttes to learn about the significance of this contact. The exposures at the contact are better due to greater topographic relief."

Above: This image shows the old and new routes of NASA's Mars Curiosity rover and is composed of color strips taken by the High Resolution Imaging Science Experiment, or HiRISE, on NASA's Mars Reconnaissance Orbiter. This new route provides excellent access to many features in the Murray Formation. And it will eventually pass by the Murray Formation's namesake, Murray Buttes, previously considered to be the entry point to Mt. Sharp. (NASA/JPL-Caltech/Univ. of Arizona)

The decision to head uphill sooner, instead of continuing to Murray Buttes, also draws from improved understanding of the region's geography provided by the rover's examinations of several outcrops during the past year. Curiosity currently is positioned at the base of the mountain along a pale, distinctive geological feature called the Murray Formation. Compared to neighboring crater-floor terrain, the rock of the Murray Formation is softer and does not preserve impact scars, as well. As viewed from orbit, it is not as well-layered as other units at the base of Mount Sharp.

Curiosity made its first close-up study last month of two Murray Formation outcrops, both revealing notable differences from the terrain explored by Curiosity during the past year. The first outcrop, called Bonanza King, proved too unstable for drilling, but was examined by the rover's instruments and determined to have high silicon content. A second outcrop, examined with the rover's telephoto Mast Camera, revealed a fine-grained, platy surface laced with sulfate-filled veins.

While some of these terrain differences are not apparent in observations made by NASA's Mars orbiters, the rover team still relies heavily on images taken by the agency's Mars Reconnaissance Orbiter (MRO) to plan Curiosity's travel routes and locations for study.

For example, MRO images helped the rover team locate mesas that are over 60 feet (18 meters) tall in an area of terrain shortly beyond Pahrump Hills, which reveal an exposure of the Murray Formation uphill and toward the south. The team plans to use Curiosity's drill to acquire a sample from this site for analysis by instruments inside the rover. The site lies at the southern end of a valley Curiosity will enter this week from the north.

Though this valley has a sandy floor the length of two football fields, the team expects it will be an easier trek than the sandy-floored Hidden Valley, where last month Curiosity's wheels slipped too much for safe crossing.

Curiosity reached its current location after its route was modified earlier this year in response to excessive wheel wear. In late 2013, the team realized a region of Martian terrain littered with sharp, embedded rocks was poking holes in four of the rover's six wheels. This damage accelerated the rate of wear and tear beyond that for which the rover team had planned. In response, the team altered the rover's route to a milder terrain, bringing the rover farther south, toward the base of Mount Sharp.

"The wheels issue contributed to taking the rover farther south sooner than planned, but it is not a factor in the science-driven decision to start ascending here rather than continuing to Murray Buttes first," said Jennifer Trosper, Curiosity Deputy Project Manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "We have been driving hard for many months to reach the entry point to Mount Sharp," Trosper said. "Now that we've made it, we'll be adjusting the operations style from a priority on driving to a priority on conducting the investigations needed at each layer of the mountain."

After landing inside Gale Crater in August 2012, Curiosity fulfilled in its first year of operations its major science goal of determining whether Mars ever offered environmental conditions favorable for microbial life. Clay-bearing sedimentary rocks on the crater floor, in an area called Yellowknife Bay, yielded evidence of a lakebed environment billions of years ago that offered fresh water, all of the key elemental ingredients for life, and a chemical source of energy for microbes.

NASA's Mars Science Laboratory Project continues to use Curiosity to assess ancient habitable environments and major changes in Martian environmental conditions. The destinations on Mount Sharp offer a series of geological layers that recorded different chapters in the environmental evolution of Mars.

posted 12-08-2014 06:26 PM               

NASA's Curiosity Rover Finds Clues to How Water Helped Shape Martian Landscape

Observations by NASA's Curiosity Rover indicate Mars' Mount Sharp was built by sediments deposited in a large lake bed over tens of millions of years.

This interpretation of Curiosity's finds in Gale Crater suggests ancient Mars maintained a climate that could have produced long-lasting lakes at many locations on the Red Planet.

Above: This illustration depicts a lake of water partially filling Mars' Gale Crater, receiving runoff from snow melting on the crater's northern rim.

"If our hypothesis for Mount Sharp holds up, it challenges the notion that warm and wet conditions were transient, local, or only underground on Mars," said Ashwin Vasavada, Curiosity deputy project scientist at NASA's Jet Propulsion Laboratory in Pasadena. "A more radical explanation is that Mars' ancient, thicker atmosphere raised temperatures above freezing globally, but so far we don't know how the atmosphere did that."

Why this layered mountain sits in a crater has been a challenging question for researchers. Mount Sharp stands about 3 miles (5 kilometers) tall, its lower flanks exposing hundreds of rock layers. The rock layers – alternating between lake, river and wind deposits -- bear witness to the repeated filling and evaporation of a Martian lake much larger and longer-lasting than any previously examined close-up.

"We are making headway in solving the mystery of Mount Sharp," said Curiosity Project Scientist John Grotzinger of the California Institute of Technology in Pasadena, California. "Where there's now a mountain, there may have once been a series of lakes."

Curiosity currently is investigating the lowest sedimentary layers of Mount Sharp, a section of rock 500 feet (150 meters) high dubbed the Murray formation. Rivers carried sand and silt to the lake, depositing the sediments at the mouth of the river to form deltas similar to those found at river mouths on Earth. This cycle occurred over and over again.

Above: This evenly layered rock photographed by the Mast Camera (Mastcam) on NASA's Curiosity Mars Rover on Aug. 7, 2014, shows a pattern typical of a lake-floor sedimentary deposit not far from where flowing water entered a lake.

"The great thing about a lake that occurs repeatedly, over and over, is that each time it comes back it is another experiment to tell you how the environment works," Grotzinger said. "As Curiosity climbs higher on Mount Sharp, we will have a series of experiments to show patterns in how the atmosphere and the water and the sediments interact. We may see how the chemistry changed in the lakes over time. This is a hypothesis supported by what we have observed so far, providing a framework for testing in the coming year."

After the crater filled to a height of at least a few hundred yards and the sediments hardened into rock, the accumulated layers of sediment were sculpted over time into a mountainous shape by wind erosion that carved away the material between the crater perimeter and what is now the edge of the mountain.

On the 5-mile (8-kilometer) journey from Curiosity's 2012 landing site to its current work site at the base of Mount Sharp, the rover uncovered clues about the changing shape of the crater floor during the era of lakes.

"We found sedimentary rocks suggestive of small, ancient deltas stacked on top of one another," said Curiosity science team member Sanjeev Gupta of Imperial College in London. "Curiosity crossed a boundary from an environment dominated by rivers to an environment dominated by lakes."

Above: This image shows an example of a thin-laminated, evenly stratified rock type that occurs in the "Pahrump Hills" outcrop at the base of Mount Sharp on Mars. The Mastcam on NASA's Curiosity Mars rover acquired this view on Oct. 28, 2014. This type of rock can form under a lake.

Despite earlier evidence from several Mars missions that pointed to wet environments on ancient Mars, modeling of the ancient climate has yet to identify the conditions that could have produced long periods warm enough for stable water on the surface.

NASA's Mars Science Laboratory Project uses Curiosity to assess ancient, potentially habitable environments and the significant changes the Martian environment has experienced over millions of years. This project is one element of NASA's ongoing Mars research and preparation for a human mission to the planet in the 2030s.

"Knowledge we're gaining about Mars' environmental evolution by deciphering how Mount Sharp formed will also help guide plans for future missions to seek signs of Martian life," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington.

posted 12-16-2014 12:59 PM               

NASA Rover Finds Active and Ancient Organic Chemistry on Mars

NASA's Mars Curiosity rover has measured a tenfold spike in methane, an organic chemical, in the atmosphere around it and detected other organic molecules in a rock-powder sample collected by the robotic laboratory's drill.

"This temporary increase in methane — sharply up and then back down — tells us there must be some relatively localized source," said Sushil Atreya of the University of Michigan, Ann Arbor, a member of the Curiosity rover science team. "There are many possible sources, biological or non-biological, such as interaction of water and rock."

Researchers used Curiosity's onboard Sample Analysis at Mars (SAM) laboratory a dozen times in a 20-month period to sniff methane in the atmosphere. During two of those months, in late 2013 and early 2014, four measurements averaged seven parts per billion. Before and after that, readings averaged only one-tenth that level.

Curiosity also detected different Martian organic chemicals in powder drilled from a rock dubbed Cumberland, the first definitive detection of organics in surface materials of Mars. These Martian organics could either have formed on Mars or been delivered to Mars by meteorites.

Above: NASA's Mars rover Curiosity drilled into this rock target, "Cumberland," during the 279th Martian day, or sol, of the rover's work on Mars (May 19, 2013) and collected a powdered sample of material from the rock's interior.

Organic molecules, which contain carbon and usually hydrogen, are chemical building blocks of life, although they can exist without the presence of life. Curiosity's findings from analyzing samples of atmosphere and rock powder do not reveal whether Mars has ever harbored living microbes, but the findings do shed light on a chemically active modern Mars and on favorable conditions for life on ancient Mars.

"We will keep working on the puzzles these findings present," said John Grotzinger, Curiosity project scientist of the California Institute of Technology in Pasadena. "Can we learn more about the active chemistry causing such fluctuations in the amount of methane in the atmosphere? Can we choose rock targets where identifiable organics have been preserved?"

Researchers worked many months to determine whether any of the organic material detected in the Cumberland sample was truly Martian. Curiosity's SAM lab detected in several samples some organic carbon compounds that were, in fact, transported from Earth inside the rover. However, extensive testing and analysis yielded confidence in the detection of Martian organics.

Identifying which specific Martian organics are in the rock is complicated by the presence of perchlorate minerals in Martian rocks and soils. When heated inside SAM, the perchlorates alter the structures of the organic compounds, so the identities of the Martian organics in the rock remain uncertain.

"This first confirmation of organic carbon in a rock on Mars holds much promise," said Curiosity Participating Scientist Roger Summons of the Massachusetts Institute of Technology in Cambridge. "Organics are important because they can tell us about the chemical pathways by which they were formed and preserved. In turn, this is informative about Earth-Mars differences and whether or not particular environments represented by Gale Crater sedimentary rocks were more or less favorable for accumulation of organic materials. The challenge now is to find other rocks on Mount Sharp that might have different and more extensive inventories of organic compounds."

Researchers also reported that Curiosity's taste of Martian water, bound into lakebed minerals in the Cumberland rock more than three billion years ago, indicates the planet lost much of its water before that lakebed formed and continued to lose large amounts after.

SAM analyzed hydrogen isotopes from water molecules that had been locked inside a rock sample for billions of years and were freed when SAM heated it, yielding information about the history of Martian water. The ratio of a heavier hydrogen isotope, deuterium, to the most common hydrogen isotope can provide a signature for comparison across different stages of a planet's history.

"It's really interesting that our measurements from Curiosity of gases extracted from ancient rocks can tell us about loss of water from Mars," said Paul Mahaffy, SAM principal investigator of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of a report published online this week by the journal Science

The ratio of deuterium to hydrogen has changed because the lighter hydrogen escapes from the upper atmosphere of Mars much more readily than heavier deuterium. In order to go back in time and see how the deuterium-to-hydrogen ratio in Martian water changed over time, researchers can look at the ratio in water in the current atmosphere and water trapped in rocks at different times in the planet's history.

Martian meteorites found on Earth also provide some information, but this record has gaps. No known Martian meteorites are even close to the same age as the rock studied on Mars, which formed about 3.9 billion to 4.6 billion years ago, according to Curiosity's measurements.

The ratio that Curiosity found in the Cumberland sample is about one-half the ratio in water vapor in today's Martian atmosphere, suggesting much of the planet's water loss occurred since that rock formed. However, the measured ratio is about three times higher than the ratio in the original water supply of Mars, based on the assumption that supply had a ratio similar to that measured in Earth's oceans. This suggests much of Mars' original water was lost before the rock formed.

The results of the Curiosity rover investigation into methane detection and the Martian organics in an ancient rock were discussed at a news briefing Tuesday (Dec. 16) at the American Geophysical Union's convention in San Francisco. The methane results are described in a paper published online this week in the journal Science by NASA scientist Chris Webster of JPL, and co-authors.

A report on organics detection in the Cumberland rock by NASA scientist Caroline Freissenet, of Goddard, and co-authors, is pending publication.

posted 03-04-2015 08:24 AM               

Testing to Diagnose Power Event in Mars Rover

NASA's Curiosity Mars rover is expected to remain stationary for several days of engineering analysis following an onboard fault-protection action on Feb. 27 that halted a process of transferring sample material between devices on the rover's robotic arm.

Telemetry received from the rover indicated that a transient short circuit occurred and the vehicle followed its programmed response, stopping the arm activity underway at the time of the irregularity in the electric current.

"We are running tests on the vehicle in its present configuration before we move the arm or drive," said Curiosity Project Manager Jim Erickson, of NASA's Jet Propulsion Laboratory in Pasadena, California. "This gives us the best opportunity to determine where the short is."

A transient short in some systems on the rover would have little effect on rover operations. In others, it could prompt the rover team to restrict use of a mechanism.

When the fault occurred, the rover was conducting an early step in the transfer of rock powder collected by the drill on the arm to laboratory instruments inside the rover. With the drill bit pointed up and the drill's percussion mechanism turned on, the rock powder was descending from collection grooves in the bit assembly into a chamber in the mechanism that sieves and portions the sample powder. The sample powder is from a rock target called "Telegraph Peak." The same transfer process was completed smoothly with samples from five previous drilling targets in 2013 and 2014.

posted 03-07-2015 10:32 AM               

Use of Rover Arm Expected to Resume in a Few Days

Managers of NASA's Curiosity Mars rover mission expect to approve resumption of rover arm movements as early as next week while continuing analysis of what appears to be an intermittent short circuit in the drill.

A fluctuation in current on Feb. 27 triggered a fault-protection response that immediately halted action by the rover during the mission's 911th Martian day, or sol. Since then, the rover team has avoided driving Curiosity or moving the rover's arm, while engineers have focused on diagnostic tests. Science observations with instruments on the rover's mast have continued, along with environmental monitoring by its weather station.

"Diagnostic testing this week has been productive in narrowing the possible sources of the transient short circuit," said Curiosity Project Manager Jim Erickson of NASA's Jet Propulsion Laboratory, Pasadena, California. "The most likely cause is an intermittent short in the percussion mechanism of the drill. After further analysis to confirm that diagnosis, we will be analyzing how to adjust for that in future drilling."

The sample-collection drill on Curiosity's robotic arm uses both rotation and hammering, or percussion, to penetrate into Martian rocks and collect pulverized rock material for delivery to analytical instruments inside the rover.

The short on Sol 911 occurred while the rover was transferring rock-powder sample from the grooves of the drill into a mechanism that sieves and portions the powder. The percussion action was in use, to shake the powder loose from the drill.

Engineers received results Thursday, March 5, from a test on Curiosity that similarly used the drill's percussion action. During the third out of 180 up-and-down repeats of the action, an apparent short circuit occurred for less than one one-hundredth of a second. Though small and fleeting, it would have been enough to trigger the fault protection that was active on Sol 911 under the parameters that were in place then.

The rover team plans further testing to characterize the intermittent short before the arm is moved from its present position, in case the short does not appear when the orientation is different.

After those tests, the team expects to finish processing the sample powder that the arm currently holds and then to deliver portions of the sample to onboard laboratory instruments. Next, Curiosity will resume climbing Mount Sharp.

posted 03-25-2015 05:57 AM               

NASA's Curiosity Rover Finds Biologically Useful Nitrogen on Mars

A team using the Sample Analysis at Mars (SAM) instrument suite aboard NASA's Curiosity rover has made the first detection of nitrogen on the surface of Mars from release during heating of Martian sediments. The nitrogen was detected in the form of nitric oxide, and could be released from the breakdown of nitrates during heating. Nitrates are a class of molecules that contain nitrogen in a form that can be used by living organisms. The discovery adds to the evidence that ancient Mars was habitable for life.

Nitrogen is essential for all known forms of life, since it is used in the building blocks of larger molecules like DNA and RNA, which encode the genetic instructions for life, and proteins, which are used to build structures like hair and nails, and to speed up or regulate chemical reactions.

However, on Earth and Mars, atmospheric nitrogen is locked up as nitrogen gas (N2) – two atoms of nitrogen bound together so strongly that they do not react easily with other molecules. The nitrogen atoms have to be separated or "fixed" so they can participate in the chemical reactions needed for life. On Earth, certain organisms are capable of fixing atmospheric nitrogen and this process is critical for metabolic activity. However, smaller amounts of nitrogen are also fixed by energetic events like lightning strikes.

Nitrate (NO3) – a nitrogen atom bound to three oxygen atoms – is a source of fixed nitrogen. A nitrate molecule can join with various other atoms and molecules; this class of molecules is known as nitrates.

There is no evidence to suggest that the fixed nitrogen molecules found by the team were created by life. The surface of Mars is inhospitable for known forms of life. Instead, the team thinks the nitrates are ancient, and likely came from non-biological processes like meteorite impacts and lightning in Mars' distant past.

Features resembling dry riverbeds and the discovery of minerals that only form in the presence of liquid water suggest that Mars was more hospitable in the remote past. The Curiosity team has found evidence that other ingredients needed for life, such as liquid water and organic matter, were present on Mars at the Curiosity site in Gale Crater billions of years ago.

"Finding a biochemically accessible form of nitrogen is more support for the ancient Martian environment at Gale Crater being habitable," said Jennifer Stern of NASA's Goddard Space Flight Center in Greenbelt, Maryland. Stern is lead author of a paper on this research published online in the Proceedings of the National Academy of Science March 23.

The team found evidence for nitrates in scooped samples of windblown sand and dust at the "Rocknest" site, and in samples drilled from mudstone at the "John Klein" and "Cumberland" drill sites in Yellowknife Bay. Since the Rocknest sample is a combination of dust blown in from distant regions on Mars and more locally sourced materials, the nitrates are likely to be widespread across Mars, according to Stern. The results support the equivalent of up to 1,100 parts per million nitrates in the Martian soil from the drill sites. The team thinks the mudstone at Yellowknife Bay formed from sediment deposited at the bottom of a lake. Previously the rover team described the evidence for an ancient, habitable environment there: fresh water, key chemical elements required by life, such as carbon, and potential energy sources to drive metabolism in simple organisms.

The samples were first heated to release molecules bound to the Martian soil, then portions of the gases released were diverted to the SAM instruments for analysis. Various nitrogen-bearing compounds were identified with two instruments: a mass spectrometer, which uses electric fields to identify molecules by their signature masses, and a gas chromatograph, which separates molecules based on the time they take to travel through a small glass capillary tube -- certain molecules interact with the sides of the tube more readily and thus travel more slowly.

Along with other nitrogen compounds, the instruments detected nitric oxide (NO -- one atom of nitrogen bound to an oxygen atom) in samples from all three sites. Since nitrate is a nitrogen atom bound to three oxygen atoms, the team thinks most of the NO likely came from nitrate which decomposed as the samples were heated for analysis. Certain compounds in the SAM instrument can also release nitrogen as samples are heated; however, the amount of NO found is more than twice what could be produced by SAM in the most extreme and unrealistic scenario, according to Stern. This leads the team to think that nitrates really are present on Mars, and the abundance estimates reported have been adjusted to reflect this potential additional source.

"Scientists have long thought that nitrates would be produced on Mars from the energy released in meteorite impacts, and the amounts we found agree well with estimates from this process," said Stern.

posted 07-06-2016 02:12 PM               

Curiosity Rover Enters Precautionary Safe Mode

The team operating NASA's Curiosity Mars rover is taking steps to return the rover to full activity following a precautionary stand-down over the Fourth of July weekend.

Curiosity is now communicating with ground controllers and is stable. The rover put itself into safe mode on July 2, ceasing most activities other than keeping itself healthy and following a prescribed sequence for resuming communications.

Engineers are working to determine the cause of safe-mode entry. Preliminary information indicates an unexpected mismatch between camera software and data-processing software in the main computer. The near-term steps toward resuming full activities begin with requesting more diagnostic information from Curiosity.

Curiosity has entered safe mode three times previously, all during 2013.

The rover landed in Mars' Gale Crater in August 2012. During its first year on Mars, the mission achieved its goal by determining that, more than 3 billion years ago, the region offered fresh-water lakes and rivers with environmental conditions well-suited to supporting microbial life, if life has ever existed on Mars. In continuing investigations, the mission is learning more about the ancient wet environments and how and when they evolved to drier and less habitable conditions.

NASA last week approved an additional two-year extension, beginning Oct. 1, 2016, for the Mars Science Laboratory Project, which developed and operates Curiosity.

posted 07-11-2016 05:25 PM               

Curiosity Mars Rover Resumes Full Operations

NASA's Curiosity Mars rover is resuming full operations today, following work by engineers to investigate why the rover put itself into a safe standby mode on July 2. The rover team brought Curiosity out of safe mode on July 9.

The most likely cause of entry into safe mode has been determined to be a software mismatch in one mode of how image data are transferred on board. Science activity planning for the rover is avoiding use of that mode, which involves writing images from some cameras' memories into files on the rover's main computer. Alternate means are available for handling and transmitting all image data.

posted 07-21-2016 07:24 PM               

NASA Mars Rover Can Choose Laser Targets on Its Own

NASA's Mars rover Curiosity is now selecting rock targets for its laser spectrometer — the first time autonomous target selection is available for an instrument of this kind on any robotic planetary mission.

Above: NASA's Curiosity Mars rover autonomously selects some targets for the laser and telescopic camera of its ChemCam instrument. For example, on-board software analyzed the Navcam image at left, chose the target indicated with a yellow dot, and pointed ChemCam for laser shots and the image at right. Credits: NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/IAS

Using software developed at NASA's Jet Propulsion Laboratory, Pasadena, California, Curiosity is now frequently choosing multiple targets per week for a laser and a telescopic camera that are parts of the rover's Chemistry and Camera (ChemCam) instrument. Most ChemCam targets are still selected by scientists discussing rocks or soil seen in images the rover has sent to Earth, but the autonomous targeting adds a new capability.

During Curiosity's nearly four years on Mars, ChemCam has inspected multiple points on more than 1,400 targets by detecting the color spectrum of plasmas generated when laser pulses zap a target — more than 350,000 total laser shots at about 10,000 points in all. ChemCam's spectrometers record the wavelengths seen through a telescope while the laser is firing. This information enables scientists to identify the chemical compositions of the targets. Through the same telescope, the instrument takes images that are of the highest resolution available from the rover's mast.

AEGIS software, for Autonomous Exploration for Gathering Increased Science, had previously been used on NASA's Mars Exploration Rover Opportunity, though less frequently and for a different type of instrument. That rover uses the software to analyze images from a wide-angle camera as the basis for autonomously selecting rocks to photograph with a narrower-angle camera. Development work on AEGIS won a NASA Software of the Year Award in 2011.

"This autonomy is particularly useful at times when getting the science team in the loop is difficult or impossible — in the middle of a long drive, perhaps, or when the schedules of Earth, Mars and spacecraft activities lead to delays in sharing information between the planets," said robotics engineer Tara Estlin, the leader of AEGIS development at JPL.

The most frequent application of AEGIS uses onboard computer analysis of images from Curiosity's stereo Navigation Camera (Navcam), which are taken routinely at each location where the rover ends a drive. AEGIS selects a target and directs ChemCam pointing, typically before the Navcam images are transmitted to Earth. This gives the team an extra jump in assessing the rover's latest surroundings and planning operations for upcoming days.

To select a target autonomously, the software's analysis of images uses adjustable criteria specified by scientists, such as identifying rocks based on their size or brightness. The criteria can be changed depending on the rover's surroundings and the scientific goals of the measurements.

Another AEGIS mode starts with images from ChemCam's own Remote Micro-Imager, rather than the Navcam, and uses image analysis to hone pointing of the laser at fine-scale targets chosen in advance by scientists. For example, scientists might select a threadlike vein or a small concretion in a rock, based on images received on Earth. AEGIS then controls the laser sharpshooting.

"Due to their small size and other pointing challenges, hitting these targets accurately with the laser has often required the rover to stay in place while ground operators fine tune pointing parameters," Estlin said. "AEGIS enables these targets to be hit on the first try by automatically identifying them and calculating a pointing that will center a ChemCam measurement on the target."

From the top of Curiosity's mast, the instrument can analyze the composition of a rock or soil target from up to about 23 feet (7 meters) away.

"AEGIS brings an extra opportunity to use ChemCam, to do more, when the interaction with scientists is limited," said ChemCam Science Operation Lead Olivier Gasnault, at the Research Institute in Astrophysics and Planetology (IRAP), of France's National Center for Scientific Research (CNRS) and the University of Toulouse, France. "It does not replace an existing mode, but complements it."

The U.S. Department of Energy's Los Alamos National Laboratory in New Mexico leads the U.S. and French team that jointly developed and operates ChemCam. IRAP is a co-developer and shares operation of the instrument with France's national space agency (CNES), NASA and Los Alamos.

The Curiosity mission is using ChemCam and other instruments on the rover as the vehicle investigates geological layers on lower Mount Sharp. The rover's extended mission is analyzing evidence about how the environment in this part of Mars changed billions of years ago from conditions well suited to microbial life — if life ever existed on Mars — to dry, inhospitable conditions.

posted 10-03-2016 07:52 PM               

NASA's Curiosity Rover Begins Next Mars Chapter

After collecting drilled rock powder in arguably the most scenic landscape yet visited by a Mars rover, NASA's Curiosity mobile laboratory is driving toward uphill destinations as part of its two-year mission extension that commenced Oct. 1.

The destinations include a ridge capped with material rich in the iron-oxide mineral hematite, about a mile-and-a-half (two-and-a-half kilometers) ahead, and an exposure of clay-rich bedrock beyond that.

These are key exploration sites on lower Mount Sharp, which is a layered, Mount-Rainier-size mound where Curiosity is investigating evidence of ancient, water-rich environments that contrast with the harsh, dry conditions on the surface of Mars today.

"We continue to reach higher and younger layers on Mount Sharp," said Curiosity Project Scientist Ashwin Vasavada, of NASA's Jet Propulsion Laboratory, Pasadena, California. "Even after four years of exploring near and on the mountain, it still has the potential to completely surprise us."

Hundreds of photos Curiosity took in recent weeks amid a cluster of mesas and buttes of diverse shapes are fresh highlights among the more than 180,000 images the rover has taken since landing on Mars in August 2012. Newly available vistas include the rover's latest self-portrait from the color camera at the end of its arm and a scenic panorama from the color camera at the top of the mast.

"Bidding good-bye to 'Murray Buttes,' Curiosity's assignment is the ongoing study of ancient habitability and the potential for life," said Curiosity Program Scientist Michael Meyer at NASA Headquarters, Washington. "This mission, as it explores the succession of rock layers, is reading the 'pages' of Martian history -- changing our understanding of Mars and how the planet has evolved. Curiosity has been and will be a cornerstone in our plans for future missions."

The component images of the self-portrait were taken near the base of one of the Murray Buttes, at the same site where the rover used its drill on Sept. 18 to acquire a sample of rock powder. An attempt to drill at this site four days earlier had halted prematurely due to a short-circuit issue that Curiosity had experienced previously, but the second attempt successfully reached full depth and collected sample material. After departing the buttes area, Curiosity delivered some of the rock sample to its internal laboratory for analysis.

This latest drill site -- the 14th for Curiosity -- is in a geological layer about 600 feet (180 meters) thick, called the Murray formation. Curiosity has climbed nearly half of this formation's thickness so far and found it consists primarily of mudstone, formed from mud that accumulated at the bottom of ancient lakes. The findings indicate that the lake environment was enduring, not fleeting. For roughly the first half of the new two-year mission extension, the rover team anticipates investigating the upper half of the Murray formation.

"We will see whether that record of lakes continues further," Vasavada said. "The more vertical thickness we see, the longer the lakes were present, and the longer habitable conditions existed here. Did the ancient environment change over time? Will the type of evidence we've found so far transition to something else?"

The "Hematite Unit" and "Clay Unit" above the Murray formation were identified from Mars orbiter observations before Curiosity's landing. Information about their composition, from the Compact Reconnaissance Imaging Spectrometer aboard NASA's Mars Reconnaissance Orbiter, made them high priorities as destinations for the rover mission. Both hematite and clay typically form in wet environments.

Vasavada said, "The Hematite and the Clay units likely indicate different environments from the conditions recorded in older rock beneath them and different from each other. It will be interesting to see whether either or both were habitable environments."

NASA approved Curiosity's second extended mission this summer on the basis of plans presented by the rover team. Additional extensions for exploring farther up Mount Sharp may be considered in the future. The Curiosity mission has already achieved its main goal of determining whether the landing region ever offered environmental conditions that would have been favorable for microbial life, if Mars has ever hosted life. The mission found evidence of ancient rivers and lakes, with a chemical energy source and all of the chemical ingredients necessary for life as we know it.

posted 12-06-2016 07:32 AM               

Curiosity Rover Team Examining New Drill Hiatus

NASA's Curiosity Mars rover is studying its surroundings and monitoring the environment, rather than driving or using its arm for science, while the rover team diagnoses an issue with a motor that moves the rover's drill.

Curiosity is at a site on lower Mount Sharp selected for what would be the mission's seventh sample-collection drilling of 2016. The rover team learned Dec. 1 that Curiosity did not complete the commands for drilling. The rover detected a fault in an early step in which the "drill feed" mechanism did not extend the drill to touch the rock target with the bit.

"We are in the process of defining a set of diagnostic tests to carefully assess the drill feed mechanism. We are using our test rover here on Earth to try out these tests before we run them on Mars," Curiosity Deputy Project Manager Steven Lee, at NASA's Jet Propulsion Laboratory in Pasadena, California, said Monday. "To be cautious, until we run the tests on Curiosity, we want to restrict any dynamic changes that could affect the diagnosis. That means not moving the arm and not driving, which could shake it."

Two among the set of possible causes being assessed are that a brake on the drill feed mechanism did not disengage fully or that an electronic encoder for the mechanism's motor did not function as expected. Lee said that workarounds may exist for both of those scenarios, but the first step is to identify why the motor did not operate properly last week.

The drill feed mechanism pushes the front of the drill outward from the turret of tools at the end of Curiosity's robotic arm. The drill collects powdered rock that is analyzed by laboratory instruments inside the rover. While arm movements and driving are on hold, the rover is using cameras and a spectrometer on its mast, and a suite of environmental monitoring capabilities.

At the rover's current location, it has driven 9.33 miles (15.01 kilometers) since landing inside Mars' Gale Crater in August 2012. That includes more than half a mile (more than 840 meters) since departing a cluster of scenic mesas and buttes — called "Murray Buttes" — in September 2016. Curiosity has climbed 541 feet (165 meters) in elevation since landing, including 144 feet (44 meters) since departing Murray Buttes.

The rover is climbing to sequentially higher and younger layers of lower Mount Sharp to investigate how the region's ancient climate changed, billions of years ago. Clues about environmental conditions are recorded in the rock layers. During its first year on Mars, the mission succeeded at its main goal by finding that the region once offered environmental conditions favorable for microbial life, if Mars has ever hosted life. The conditions in long-lived ancient freshwater Martian lake environments included all of the key chemical elements needed for life as we know it, plus a chemical source of energy that is used by many microbes on Earth.

Curiosity's drill, as used at all 15 of the rock targets drilled so far, combines hammering action and rotating-bit action to penetrate the targets and collect sample material. The drilling attempt last week was planned as the mission's first using a non-percussion drilling method that relies only on the drill's rotary action. Short-circuiting in the percussion mechanism has occurred intermittently and unpredictably several times since first seen in February 2015.

"We still have percussion available, but we would like to be cautious and use it for targets where we really need it, and otherwise use rotary-only where that can give us a sample," said Curiosity Project Scientist Ashwin Vasavada at JPL.

posted 12-13-2016 08:48 PM               

Mars Rock-Ingredient Stew Seen as Plus for Habitability

NASA's Curiosity rover is climbing a layered Martian mountain and finding evidence of how ancient lakes and wet underground environments changed, billions of years ago, creating more diverse chemical environments that affected their favorability for microbial life.

Above: This pair of drawings depicts the same location at Gale Crater on at two points in time: now and billions of years ago. Water moving beneath the ground, as well as water above the surface in ancient rivers and lakes, provided favorable conditions for microbial life, if Mars has ever hosted life.

Hematite, clay minerals and boron are among the ingredients found to be more abundant in layers farther uphill, compared with lower, older layers examined earlier in the mission. Scientists are discussing what these and other variations tell about conditions under which sediments were initially deposited, and about how groundwater moving later through the accumulated layers altered and transported ingredients.

Effects of this groundwater movement are most evident in mineral veins. The veins formed where cracks in the layers were filled with chemicals that had been dissolved in groundwater. The water with its dissolved contents also interacted with the rock matrix surrounding the veins, altering the chemistry both in the rock and in the water.

"There is so much variability in the composition at different elevations, we've hit a jackpot," said John Grotzinger, of Caltech in Pasadena, California. He and other members of Curiosity's science team presented an update about the mission Tuesday, Dec. 13, in San Francisco during the fall meeting of the American Geophysical Union. As the rover examines higher, younger layers, researchers are impressed by the complexity of the lake environments when clay-bearing sediments were being deposited, and also the complexity of the groundwater interactions after the sediments were buried.

'Chemical Reactor'

"A sedimentary basin such as this is a chemical reactor," Grotzinger said. "Elements get rearranged. New minerals form and old ones dissolve. Electrons get redistributed. On Earth, these reactions support life."

Whether Martian life has ever existed is still unknown. No compelling evidence for it has been found. When Curiosity landed in Mars' Gale Crater in 2012, the mission's main goal was to determine whether the area ever offered an environment favorable for microbes.

The crater's main appeal for scientists is geological layering exposed in the lower portion of its central mound, Mount Sharp. These exposures offer access to rocks that hold a record of environmental conditions from many stages of early Martian history, each layer younger than the one beneath it. The mission succeeded in its first year, finding that an ancient Martian lake environment had all the key chemical ingredients needed for life, plus chemical energy available for life. Now, the rover is climbing lower on Mount Sharp to investigate how ancient environmental conditions changed over time.

"We are well into the layers that were the main reason Gale Crater was chosen as the landing site," said Curiosity Deputy Project Scientist Joy Crisp of NASA's Jet Propulsion Laboratory, in Pasadena, California. "We are now using a strategy of drilling samples at regular intervals as the rover climbs Mount Sharp. Earlier we chose drilling targets based on each site's special characteristics. Now that we're driving continuously through the thick basal layer of the mountain, a series of drill holes will build a complete picture."

Four recent drilling sites, from "Oudam" this past June through "Sebina" in October, are each spaced about 80 feet (about 25 meters) apart in elevation. This uphill pattern allows the science team to sample progressively younger layers that reveal Mount Sharp's ancient environmental history.

Changing Environments

One clue to changing ancient conditions is the mineral hematite. It has replaced less-oxidized magnetite as the dominant iron oxide in rocks Curiosity has drilled recently, compared with the site where Curiosity first found lakebed sediments. "Both samples are mudstone deposited at the bottom of a lake, but the hematite may suggest warmer conditions, or more interaction between the atmosphere and the sediments," said Thomas Bristow of NASA Ames Research Center, Moffett Field, California. He helps operate the Chemistry and Mineralogy (CheMin) laboratory instrument inside the rover, which identifies minerals in collected samples.

Chemical reactivity occurs on a gradient of chemical ingredients' strength at donating or receiving electrons. Transfer of electrons due to this gradient can provide energy for life. An increase in hematite relative to magnetite indicates an environmental change in the direction of tugging electrons more strongly, causing a greater degree of oxidation in iron.

Another ingredient increasing in recent measurements by Curiosity is the element boron, which the rover's laser-shooting Chemistry and Camera (ChemCam) instrument has been detecting within mineral veins that are mainly calcium sulfate. "No prior mission has detected boron on Mars," said Patrick Gasda of the U.S. Department of Energy's Los Alamos National Laboratory, Los Alamos, New Mexico. "We're seeing a sharp increase in boron in vein targets inspected in the past several months." The instrument is quite sensitive; even at the increased level, boron makes up only about one-tenth of one percent of the rock composition.

'Dynamic System'

Boron is famously associated with arid sites where much water has evaporated away -- think of the borax that mule teams once hauled from Death Valley. However, environmental implications of the minor amount of boron found by Curiosity are less straightforward than for the increase in hematite.

Scientists are considering at least two possibilities for the source of boron that groundwater left in the veins. Perhaps evaporation of a lake formed a boron-containing deposit in an overlying layer, not yet reached by Curiosity, then water later re-dissolved the boron and carried it down through a fracture network into older layers, where it accumulated along with fracture-filling vein minerals. Or perhaps changes in the chemistry of clay-bearing deposits, such as evidenced by the increased hematite, affected how groundwater picked up and dropped off boron within the local sediments.

"Variations in these minerals and elements indicate a dynamic system," Grotzinger said. "They interact with groundwater as well as surface water. The water influences the chemistry of the clays, but the composition of the water also changes. We are seeing chemical complexity indicating a long, interactive history with the water. The more complicated the chemistry is, the better it is for habitability. The boron, hematite and clay minerals underline the mobility of elements and electrons, and that is good for life."

posted 03-21-2017 04:42 PM               

Break in Raised Tread on Curiosity Wheel

Two of the raised treads, called grousers, on the left middle wheel of NASA's Curiosity Mars rover broke during the first quarter of 2017, including the one seen partially detached at the top of the wheel in this image from the Mars Hand Lens Imager (MAHLI) camera on the rover's arm.

This image was taken on March 19, 2017, as part of a set used by rover team members to inspect the condition of the rover's six wheels during the 1,641st Martian day, or sol, of Curiosity's work on Mars.

Holes and tears in the wheels worsened significantly during 2013 as Curiosity was crossing terrain studded with sharp rocks on the route from near its 2012 landing site to the base of Mount Sharp. Team members have used MAHLI systematically since then to watch for when any of the zig-zag shaped grousers begin to break. The last prior set of wheel-inspection images from before Sol 1641 was taken on Jan. 27, 2017, (Sol 1591) and revealed no broken grousers.

Longevity testing with identical aluminum wheels on Earth indicates that when three grousers on a given wheel have broken, that wheel has reached about 60 percent of its useful life. Curiosity has driven well over 60 percent of the amount needed for reaching all the geological layers planned as the mission's science destinations, so the start of seeing broken grousers is not expected to affect the mission's operations.

As with other images from Curiosity's cameras, all of the wheel-inspection exposures are available in the raw images collections.

Curiosity's six aluminum wheels are about 20 inches (50 centimeters) in diameter and 16 inches (40 centimeters) wide. Each of the six wheels has its own drive motor, and the four corner wheels also have steering motors.

posted 02-28-2018 03:27 PM               

Sol 1973: Go for Drilling!

Curiosity is officially go for drilling the "Lake Orcadie" target! After more than a year's wait for the drill to come back online, the rover planners and engineers are confident and ready to proceed with a test of a new drilling method in the coming days.

Because there is only so much data volume and rover power to go around, performing drill activities must temporarily come at the expense of scientific investigations (although you'd be pressed to find a disappointed science team member this week, as the drilling campaign will bring loads of new scientific data!). As a result, with the exception of some environmental observations by the Rover Environmental Monitoring Station (REMS) instrument, today's plan does not have any targeted scientific observations within it. Today will instead be dedicated to drill preload activities and imaging for engineering and rover planning purposes in preparation for a full test of the revised drilling operations.

The name "Lake Orcadie" refers to an ancient lake that was once located in Scotland and is now a series of sedimentary deposits preserved in the geologic record. The Lake Orcadie sediments in Scotland helped geologists to reconstruct the environmental history of the Devonian period on Earth, when fish began to diversify. Considering this target will be the first drill location on Vera Rubin Ridge (VRR), perhaps these new data will help inform us as to what sort of geologic and environmental conditions were present during this time in the history of Gale crater.

posted 06-05-2018 07:58 AM               

Mars Curiosity's Labs Are Back in Action

NASA's Curiosity rover is analyzing drilled samples on Mars in one of its onboard labs for the first time in more than a year.

Above: The drill bit of NASA's Curiosity Mars rover over one of the sample inlets on the rover's deck. The inlets lead to Curiosity's onboard laboratories. This image was taken on Sol 2068 by the rover's Mast Camera (Mastcam). (NASA/JPL-Caltech/MSSS)

"This was no small feat. It represents months and months of work by our team to pull this off," said Jim Erickson, project manager of the Mars Science Laboratory mission, which is led by NASA's Jet Propulsion Laboratory in Pasadena, California. The Curiosity rover is part of the MSL mission. "JPL's engineers had to improvise a new way for the rover to drill rocks on Mars after a mechanical problem took the drill offline in December 2016."

The rover drilled its last scheduled rock sample in October 2016.

On May 20, a technique called "feed extended drilling" allowed Curiosity to drill its first rock sample since October 2016; on May 31, an additional technique called "feed extended sample transfer" successfully trickled rock powder into the rover for processing by its mineralogy laboratory. Delivery to its chemistry laboratory will follow in the week ahead.

Testing of both the new drilling method and sample delivery will continue to be refined as Curiosity's engineers study their results from Mars. But this is a major milestone for the mission, said Ashwin Vasavada of JPL, the mission's project scientist.

"The science team was confident that the engineers would deliver -- so confident that we drove back to a site that we missed drilling before. The gambit paid off, and we now have a key sample we might have never gotten," Vasavada said. "It's quite remarkable to have a moment like this, five years into the mission. It means we can resume studying Mount Sharp, which Curiosity is climbing, with our full range of scientific tools."

The new sample transfer technique allows Curiosity to position its drill over two small inlets on top of the rover's deck, trickling in the appropriate amount of rock powder for the onboard laboratories to do their analyses.

This delivery method had already been successfully tested at JPL. But that's here on Earth; on Mars, the thin, dry atmosphere provides very different conditions for powder falling out of the drill.

"On Mars we have to try and estimate visually whether this is working, just by looking at images of how much powder falls out," said John Michael Moorokian of JPL, the engineer who led development of the new sample delivery method. "We're talking about as little as half a baby aspirin worth of sample."

Too little powder, and the laboratories can't provide accurate analyses. Too much, and it could overfill the instruments, clogging parts or contaminating future measurements. A successful test of the delivery method on May 22 led to even further improvements in the delivery technique.

Part of the challenge is that Curiosity's drill is now permanently extended. That new configuration no longer gives it access to a special device that sieves and portions drilled samples in precise amounts. That device, called the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA), played an important role in delivering measured portions of sample to the laboratories inside the rover.

posted 06-07-2018 01:05 PM               

NASA Finds Ancient Organic Material, Mysterious Methane on Mars

NASA's Curiosity rover has found new evidence preserved in rocks on Mars that suggests the planet could have supported ancient life, as well as new evidence in the Martian atmosphere that relates to the search for current life on the Red Planet. While not necessarily evidence of life itself, these findings are a good sign for future missions exploring the planet's surface and subsurface.

The new findings – "tough" organic molecules in three-billion-year-old sedimentary rocks near the surface, as well as seasonal variations in the levels of methane in the atmosphere – appear in the June 8 edition of the journal Science.

Organic molecules contain carbon and hydrogen, and also may include oxygen, nitrogen and other elements. While commonly associated with life, organic molecules also can be created by non-biological processes and are not necessarily indicators of life.

"With these new findings, Mars is telling us to stay the course and keep searching for evidence of life," said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters, in Washington. "I'm confident that our ongoing and planned missions will unlock even more breathtaking discoveries on the Red Planet."

"Curiosity has not determined the source of the organic molecules," said Jen Eigenbrode of NASA's Goddard Space Flight Center in Greenbelt, Maryland, who is lead author of one of the two new Science papers. "Whether it holds a record of ancient life, was food for life, or has existed in the absence of life, organic matter in Martian materials holds chemical clues to planetary conditions and processes."

Although the surface of Mars is inhospitable today, there is clear evidence that in the distant past, the Martian climate allowed liquid water – an essential ingredient for life as we know it – to pool at the surface. Data from Curiosity reveal that billions of years ago, a water lake inside Gale Crater held all the ingredients necessary for life, including chemical building blocks and energy sources.

"The Martian surface is exposed to radiation from space. Both radiation and harsh chemicals break down organic matter," said Eigenbrode. "Finding ancient organic molecules in the top five centimeters of rock that was deposited when Mars may have been habitable, bodes well for us to learn the story of organic molecules on Mars with future missions that will drill deeper."

Seasonal Methane Releases

In the second paper, scientists describe the discovery of seasonal variations in methane in the Martian atmosphere over the course of nearly three Mars years, which is almost six Earth years. This variation was detected by Curiosity's Sample Analysis at Mars (SAM) instrument suite.

Water-rock chemistry might have generated the methane, but scientists cannot rule out the possibility of biological origins. Methane previously had been detected in Mars' atmosphere in large, unpredictable plumes. This new result shows that low levels of methane within Gale Crater repeatedly peak in warm, summer months and drop in the winter every year.

"This is the first time we've seen something repeatable in the methane story, so it offers us a handle in understanding it," said Chris Webster of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, lead author of the second paper. "This is all possible because of Curiosity's longevity. The long duration has allowed us to see the patterns in this seasonal 'breathing.'"

Finding Organic Molecules

To identify organic material in the Martian soil, Curiosity drilled into sedimentary rocks known as mudstone from four areas in Gale Crater. This mudstone gradually formed billions of years ago from silt that accumulated at the bottom of the ancient lake. The rock samples were analyzed by SAM, which uses an oven to heat the samples (in excess of 900 degrees Fahrenheit, or 500 degrees Celsius) to release organic molecules from the powdered rock.

SAM measured small organic molecules that came off the mudstone sample – fragments of larger organic molecules that don't vaporize easily. Some of these fragments contain sulfur, which could have helped preserve them in the same way sulfur is used to make car tires more durable, according to Eigenbrode.

The results also indicate organic carbon concentrations on the order of 10 parts per million or more. This is close to the amount observed in Martian meteorites and about 100 times greater than prior detections of organic carbon on Mars' surface. Some of the molecules identified include thiophenes, benzene, toluene, and small carbon chains, such as propane or butene.

In 2013, SAM detected some organic molecules containing chlorine in rocks at the deepest point in the crater. This new discovery builds on the inventory of molecules detected in the ancient lake sediments on Mars and helps explains why they were preserved.

Finding methane in the atmosphere and ancient carbon preserved on the surface gives scientists confidence that NASA's Mars 2020 rover and ESA's (European Space Agency's) ExoMars rover will find even more organics, both on the surface and in the shallow subsurface.

These results also inform scientists' decisions as they work to find answers to questions concerning the possibility of life on Mars.

"Are there signs of life on Mars?" said Michael Meyer, lead scientist for NASA's Mars Exploration Program, at NASA Headquarters. "We don't know, but these results tell us we are on the right track."

This work was funded by NASA's Mars Exploration Program for the agency's Science Mission Directorate (SMD) in Washington. Goddard provided the SAM instrument. JPL built the rover and manages the project for SMD.

posted 01-28-2019 07:54 PM               

Curiosity Says Farewell to Mars' Vera Rubin Ridge

NASA's Curiosity rover has taken its last selfie on Vera Rubin Ridge and descended toward a clay region of Mount Sharp. The twisting ridge on Mars has been the rover's home for more than a year, providing scientists with new samples - and new questions - to puzzle over.

Above: A selfie taken by NASA's Curiosity Mars rover on Sol 2291 (January 15) at the "Rock Hall" drill site, located on Vera Rubin Ridge. (NASA/JPL-Caltech)

On Dec. 15, Curiosity drilled its 19th sample at a location on the ridge called Rock Hall. On Jan. 15, the spacecraft used its Mars Hand Lens Imager (MAHLI) camera on the end of its robotic arm to take a series of 57 pictures, which were stitched together into this selfie. The "Rock Hall" drill hole is visible to the lower left of the rover; the scene is dustier than usual at this time of year due to a regional dust storm.

Curiosity has been exploring the ridge since September of 2017. It's now headed into the "clay-bearing unit," which sits in a trough just south of the ridge. Clay minerals in this unit may hold more clues about the ancient lakes that helped form the lower levels on Mount Sharp.

posted 02-22-2019 04:07 PM               

After a Reset, Curiosity Is Operating Normally

NASA's Curiosity rover is busy making new discoveries on Mars. The rover has been climbing Mount Sharp since 2014 and recently reached a clay region that may offer new clues about the ancient Martian environment's potential to support life.

Curiosity encountered a hurdle last Friday, when a hiccup during boot-up interrupted its planned activities and triggered a protective safe mode. The rover was brought out of this mode on Tuesday, Feb. 19, and is otherwise operating normally, having successfully booted up over 30 times without further issues.

Throughout the weekend, Curiosity was sending and receiving technical data, communicating with the team in order to help them pinpoint the cause of the issue.

"We're still not sure of its exact cause and are gathering the relevant data for analysis," said Steven Lee, Curiosity's deputy project manager at NASA's Jet Propulsion Laboratory in Pasadena, California. JPL leads the Curiosity mission. "The rover experienced a one-time computer reset but has operated normally ever since, which is a good sign," he added. "We're currently working to take a snapshot of its memory to better understand what might have happened."

Out of an abundance of caution, Lee said, science operations will remain on hold until the issue is better understood.

"In the short term, we are limiting commands to the vehicle to minimize changes to its memory," Lee said. "We don't want to destroy any evidence of what might have caused the computer reset. As a result, we expect science operations will be suspended for a short period of time."

Curiosity is one of two NASA spacecraft actively studying the Martian surface. InSight, a stationary lander, reached the planet on Nov. 26; Opportunity, which ran for more than 14 years, has completed its mission.

Curiosity has been exploring a region — dubbed "Glen Torridon" — where clay minerals can be seen from orbit. Clay minerals, which form in water, are especially interesting to the rover's science team. The rover was designed specifically to study ancient environments that could have supported life, and water plays a key role in determining that.

While the engineers address the computer reset, the science team will continue studying the images and other data that have been collected from Glen Torridon. A potential drill location has been sighted just 656 feet (200 meters) away.

"The science team is eager to drill our first sample from this fascinating location," said JPL's Ashwin Vasavada, Curiosity's project scientist. "We don't yet understand how this area fits into the overall history of Mount Sharp, so our recent images give us plenty to think about."

posted 08-05-2019 05:17 PM               

New Finds for Mars Rover, Seven Years After Landing

NASA's Curiosity rover has come a long way since touching down on Mars seven years ago. It has traveled a total of 13 miles (21 kilometers) and ascended 1,207 feet (368 meters) to its current location. Along the way, Curiosity discovered Mars had the conditions to support microbial life in the ancient past, among other things.

Above: This panorama of a location called "Teal Ridge" was captured on Mars by the Mast Camera, or Mastcam, on NASA's Curiosity rover on June 18, 2019, the 2,440th Martian day, or sol, of the mission. (NASA/JPL-Caltech/MSSS)

And the rover is far from done, having just drilled its 22nd sample from the Martian surface. It has a few more years before its nuclear power system degrades enough to significantly limit operations. After that, careful budgeting of its power will allow the rover to keep studying the Red Planet.

Curiosity is now halfway through a region scientists call the "clay-bearing unit" on the side of Mount Sharp, inside of Gale Crater. Billions of years ago, there were streams and lakes within the crater. Water altered the sediment deposited within the lakes, leaving behind lots of clay minerals in the region. That clay signal was first detected from space by NASA's Mars Reconnaissance Orbiter (MRO) a few years before Curiosity launched.

"This area is one of the reasons we came to Gale Crater," said Kristen Bennett of the U.S. Geological Survey, one of the co-leads for Curiosity's clay-unit campaign. "We've been studying orbiter images of this area for 10 years, and we're finally able to take a look up close."

Rock samples that the rover has drilled here have revealed the highest amounts of clay minerals found during the mission. But Curiosity has detected similarly high amounts of clay on other parts of Mount Sharp, including in areas where MRO didn't detect clay. That's led scientists to wonder what is causing the findings from orbit and the surface to differ.

The science team is thinking through possible reasons as to why the clay minerals here stood out to MRO. The rover encountered a "parking lot full of gravel and pebbles" when it first entered the area, said the campaign's other co-lead, Valerie Fox of Caltech. One idea is that the pebbles are the key: Although the individual pebbles are too small for MRO to see, they may collectively appear to the orbiter as a single clay signal scattered across the area. Dust also settles more readily over flat rocks than it does over the pebbles; that same dust can obscure the signals seen from space. The pebbles were too small for Curiosity to drill into, so the science team is looking for other clues to solve this puzzle.

Curiosity exited the pebble parking lot back in June and started to encounter more complex geologic features. It stopped to take a 360-degree panorama at an outcrop called "Teal Ridge." More recently, it took detailed images of "Strathdon," a rock made of dozens of sediment layers that have hardened into a brittle, wavy heap. Unlike the thin, flat layers associated with lake sediments Curiosity has studied, the wavy layers in these features suggest a more dynamic environment. Wind, flowing water or both could have shaped this area.

Both Teal Ridge and Strathdon represent changes in the landscape. "We're seeing an evolution in the ancient lake environment recorded in these rocks," said Fox. "It wasn't just a static lake. It's helping us move from a simplistic view of Mars going from wet to dry. Instead of a linear process, the history of water was more complicated."

Curiosity is discovering a richer, more complex story behind the water on Mount Sharp - a process Fox likened to finally being able to read the paragraphs in a book - a dense book, with pages torn out, but a fascinating tale to piece together.

posted 01-21-2020 11:05 AM               

Sols 2649-2652: Curiosity Loses Its Attitude

Written by Dawn Sumner, Planetary Geologist at University of California Davis

Knowing where our bodies are helps us move through the world. We know if we are standing or sitting, if our arms are out or by our sides (or for some people, not there at all). This body awareness is essential for staying safe.

Rovers also need to know where their bodies are relative to their surroundings. Curiosity stores its body attitude in memory, things like the orientation of each joint, which instrument on the end of its arm is pointing down, and how close APXS is to the ground. It also stores its knowledge of the environment, things like how steep the slope is, where the big rocks are, and where the bedrock sticks out in a dangerous way.

Curiosity evaluates this information before any motor is activated to make sure the movement can be executed safely. When the answer is no — or even maybe not — Curiosity stops without turning the motor. This conservative approach helps keep Curiosity from hitting its arm on rocks, driving over something dangerous, or pointing an unprotected camera at the sun. These safety checks require an accurate knowledge of the rover position within its environment and are an essential part of good engineering practice. They have kept Curiosity safe over the years.

Partway through its last set of activities, Curiosity lost its orientation. Some knowledge of its attitude was not quite right, so it couldn't make the essential safety evaluation. Thus, Curiosity stopped moving, freezing in place until its knowledge of its orientation can be recovered.

Curiosity kept sending us information, so we know what happened and can develop a recovery plan. That is exactly what we did today [Jan. 20, 2020]: The engineers on the team built a plan to inform Curiosity of its attitude and to confirm what happened. We want Curiosity to recover its ability to make its safety checks, and we also want to know if there is anything we can do to prevent a similar problem in the future. This approach helps keep our rover safe.