MarsNews.com
November 12th, 2019

With Mars Methane Mystery Unsolved, Curiosity Serves Scientists a New One: Oxygen

Credits: Melissa Trainer/Dan Gallagher/NASA Goddard

For the first time in the history of space exploration, scientists have measured the seasonal changes in the gases that fill the air directly above the surface of Gale Crater on Mars. As a result, they noticed something baffling: oxygen, the gas many Earth creatures use to breathe, behaves in a way that so far scientists cannot explain through any known chemical processes.

Over the course of three Mars years (or nearly six Earth years) an instrument in the Sample Analysis at Mars (SAM) portable chemistry lab inside the belly of NASA’s Curiosity rover inhaled the air of Gale Crater and analyzed its composition. The results SAM spit out confirmed the makeup of the Martian atmosphere at the surface: 95% by volume of carbon dioxide (CO2), 2.6% molecular nitrogen (N2), 1.9% argon (Ar), 0.16% molecular oxygen (O2), and 0.06% carbon monoxide (CO). They also revealed how the molecules in the Martian air mix and circulate with the changes in air pressure throughout the year. These changes are caused when CO2 gas freezes over the poles in the winter, thereby lowering the air pressure across the planet following redistribution of air to maintain pressure equilibrium. When CO2 evaporates in the spring and summer and mixes across Mars, it raises the air pressure.

Within this environment, scientists found that nitrogen and argon follow a predictable seasonal pattern, waxing and waning in concentration in Gale Crater throughout the year relative to how much CO2 is in the air. They expected oxygen to do the same. But it didn’t. Instead, the amount of the gas in the air rose throughout spring and summer by as much as 30%, and then dropped back to levels predicted by known chemistry in fall. This pattern repeated each spring, though the amount of oxygen added to the atmosphere varied, implying that something was producing it and then taking it away.

October 8th, 2019

Curiosity rover finds an ancient oasis on Mars

Filled with briny lakes, the Quisquiro salt flat in South America’s Altiplano represents the kind of landscape that scientists think may have existed in Gale Crater, which NASA’s Curiosity rover is exploring. Credit: Maksym Bocharov

If you could travel back in time 3.5 billion years, what would Mars look like? The picture is evolving among scientists working with NASA’s Curiosity rover.

Imagine ponds dotting the floor of Gale Crater, the 100-mile-wide (150-kilometer-wide) ancient basin that Curiosity is exploring. Streams might have laced the crater’s walls, running toward its base. Watch history in fast forward, and you’d see these waterways overflow then dry up, a cycle that probably repeated itself numerous times over millions of years.

That is the landscape described by Curiosity scientists in a Nature Geoscience paper published today. The authors interpret rocks enriched in mineral salts discovered by the rover as evidence of shallow briny ponds that went through episodes of overflow and drying. The deposits serve as a watermark created by climate fluctuations as the Martian environment transitioned from a wetter one to the freezing desert it is today.

Scientists would like to understand how long this transition took and when exactly it occurred. This latest clue may be a sign of findings to come as Curiosity heads toward a region called the “sulfate-bearing unit,” which is expected to have formed in an even drier environment. It represents a stark difference from lower down the mountain, where Curiosity discovered evidence of persistent freshwater lakes.

July 11th, 2019

NASA’s Mars Curiosity rover still taking a beating from red planet rocks

The Curiosity rover’s wheel has some damage in this image from July 7. NASA/JPL-Caltech/MSSS

NASA’s Curiosity rover is equipped with tough aluminum wheels, but they’re not getting off easy on Mars. The red planet’s rocky landscape continues to take a toll on the rover, as new images of wheel damage show.

The rover used the Mars Hand Lens Imager (MAHLI) camera on the the end of its robotic arm to take a close look at its wheels on July 7. This is pretty much the rover equivalent of inspecting the bottom of your boots after going for a rocky hike.

The wheels are dented and pockmarked from traversing rough ground. What’s most concerning are the many cracks and outright holes visible across the treads.

While the damage looks scary, the wheels are actually doing a pretty good job of hanging in there.

“Although the wheels have developed some holes, the testing and modeling that have been done since early 2014 indicate that Curiosity can still travel a number of kilometers on these wheels,” Curiosity team member Roger Craig Wiens wrote in a mission update.

The rover has traveled 12.99 miles (20.91 kilometers) since reaching Mars in 2012, so the wheels should still be serviceable for quite some time.

May 28th, 2019

Curiosity Gazes Upon Noctilucent Clouds Over Gale Crater

Just imagine this scene. You’re on Mars, in Gale crater, with Curiosity. The sun has just set, and the temperature is falling rapidly. You look up. You see brilliant, wispy clouds, still sunlit even though night has fallen where you’re standing. They’re high in elevation, so the Sun can still reach them. As you stand there, skygazing, feeling increasingly chilled, the noctilucent clouds waft along in the Martian air, dimming from east to west as the Sun sets on them.

Curiosity has, in fact, been looking up after sunset recently. It’s been taking Navcam photos, and the camera’s reasonably broad field of view (45 degrees) lets it take in a lot of clouds, giving all of us back on Earth a chance to see them, too.

April 5th, 2019

Curiosity Captured Two Solar Eclipses on Mars

Curiosity Observes Phobos Eclipse: Sol 2359: This series of images shows the Martian moon Phobos as it crossed in front of the Sun, as seen by NASA’s Curiosity Mars rover on Tuesday, March 26, 2019 (Sol 2359). Image credit: NASA/JPL-Caltech/MSSS

When NASA’s Curiosity Mars rover landed in 2012, it brought along eclipse glasses. The solar filters on its Mast Camera (Mastcam) allow it to stare directly at the Sun. Over the past few weeks, Curiosity has been putting them to good use by sending back some spectacular imagery of solar eclipses caused by Phobos and Deimos, Mars’ two moons.

Phobos, which is about 7 miles (11.5 kilometers) across, was imaged on March 26, 2019 (the 2,359th sol, or Martian day, of Curiosity’s mission); Deimos, which is about 1.5 miles (2.3 kilometers) across, was photographed on March 17, 2019 (Sol 2350). Phobos doesn’t completely cover the Sun, so it would be considered an annular eclipse. Because Deimos is so small compared to the disk of the Sun, scientists would say it’s transiting the Sun.

In addition to capturing each moon crossing in front of the Sun, one of Curiosity’s Navigation Cameras (Navcams) observed the shadow of Phobos on March 25, 2019 (Sol 2358). As the moon’s shadow passed over the rover during sunset, it momentarily darkened the light.

April 1st, 2019

Mars Express matches methane spike measured by Curiosity

Mars Express results ESA/Giuranna et al (2019)

A reanalysis of data collected by ESA’s Mars Express during the first 20 months of NASA’s Curiosity mission found one case of correlated methane detection, the first time an in-situ measurement has been independently confirmed from orbit.

Reports of methane in the martian atmosphere have been intensely debated, with Mars Express contributing one of the first measurements from orbit in 2004, shortly after its arrival at the Red Planet.

The molecule attracts such attention because on Earth methane is generated by living organisms, as well as geological processes. Because it can be destroyed quickly by atmospheric processes, any detection of the molecule in the martian atmosphere means it must have been released relatively recently – even if the methane itself was produced millions or billions of years ago and lay trapped in underground reservoirs until now.

While spacecraft and telescopic observations from Earth have in general reported no or very low detections of methane, or measurements right at the limit of the instruments’ capabilities, a handful of spurious spikes, along with Curiosity’s reported seasonal variation at its location in Gale Crater, raise the exciting question of how it is being generated and destroyed in present times.

Now, for the first time, a strong signal measured by the Curiosity rover on 15 June 2013 is backed up by an independent observation by the Planetary Fourier Spectrometer (PFS) onboard Mars Express the next day, as the spacecraft flew over Gale Crater.

January 31st, 2019

‘Mars Buggy’ Curiosity Measures a Mountain’s Gravity

Side-by-side images depict NASA’s Curiosity rover (illustration at left) and a moon buggy driven during the Apollo 16 mission. Credit: NASA/JPL-Caltech

Apollo 17 astronauts drove a moon buggy across the lunar surface in 1972, measuring gravity with a special instrument. There are no astronauts on Mars, but a group of clever researchers realized they havejust the tools for similar experiments with the Martian buggy they’re operating.

In a new paper in Science, the researchers detail how they repurposed sensors used to drive the Curiosity rover and turned them into gravimeters, which measure changes in gravitational pull. That enabled them to measure the subtle tug from rock layers on lower Mount Sharp, which rises 3 miles (5 kilometers) from the base of Gale Crater and which Curiosity has been climbing since 2014. The results? It turns out the density of those rock layers is much lower than expected.

Just like a smartphone, Curiosity carries accelerometers and gyroscopes. Moving your smartphone allows these sensors to determine its location and which way it’s facing. Curiosity’s sensors do the same thing but with far more precision, playing a crucial role in navigating the Martian surface on each drive. Knowing the rover’s orientation also lets engineers accurately point its instruments and multidirectional, high-gain antenna.

By happy coincidence, the rover’s accelerometers can be used like Apollo 17’s gravimeter. The accelerometers detect the gravity of the planet whenever the rover stands still. Using engineering data from the first five years of the mission, the paper’s authors measured the gravitational tug of Mars on the rover. As Curiosity ascends Mount Sharp, the mountain adds additional gravity – but not as much as scientists expected.

“The lower levels of Mount Sharp are surprisingly porous,” said lead author Kevin Lewis of Johns Hopkins University. “We know the bottom layers of the mountain were buried over time. That compacts them, making them denser. But this finding suggests they weren’t buried by as much material as we thought.”

December 10th, 2018

NASA’s Lincoln penny on Mars shows how hard the wind blows




Image of the MAHLI calibration target before Image of the MAHLI calibration target after

The global dust storm on Mars earlier this year coated NASA’s rovers in a layer of red planet grime. A new set of images shows how the current windy season is cleaning off the Curiosity rover.

Curiosity team member and planetary scientist Abigail Fraeman posted an update to the mission blog on Wednesday with two images taken by the Mars Hand Lens Imager (MAHLI) camera on the rover’s arm.

The first image dates to Sept. 4 and shows the coin used to help calibrate Curiosity’s camera and test its performance. The penny is coated with Mars dust, a reminder of the powerful storm that knocked NASA’s Opportunity rover out of contact in June.

The second image is from Dec. 2 and shows a much cleaner penny. “Dust has certainly been blowing around in Gale Crater lately,” writes Fraeman.

November 29th, 2018

Opinion: Mars Beckons

Niv Bavarsky

The science and technology behind NASA’s latest space explorer to land on Mars are so awe-inducing that it’s hardly surprising when scientists commenting on the triumph drop their usual jargon to speak like excited schoolchildren.

“It’s nice and dirty; I like that,” was how Bruce Banerdt, the principal investigator behind the InSight mission, reacted when, shortly after setting down Monday on the flat and featureless Martian plain known as the Elysium Planitia, the lander beamed back an image speckled with red dust. “This image is actually a really good argument for why you put a dust cover on a camera. Good choice, right?”

Unlike the [rovers], InSight — Interior Exploration using Seismic Investigations, Geodesy and Heat Transport — is meant to stay in one spot and deploy instruments to measure marsquakes (yes, on Earth they’re “earthquakes”) in order to learn about what’s going on in the innards of the planet. One gizmo will take Mars’s temperature by hammering itself 16 feet below the surface. Deploying the instruments alone is expected to take two months, and the entire mission is meant to last a Martian year, roughly two Earth years.

What for? A random sampling of comments from the public suggests not everyone is convinced that digging on Mars is money well spent. But the basic answer is that whether it’s practical or not, humans will continue to explore the heavens so long as the moon, Mars and the myriad celestial bodies beyond fire our imagination and curiosity. What happened in the earliest days of the universe? How were Earth and its fellow planets formed? And the question of questions: Is there life out there?

June 19th, 2018

Curiosity Rover Stays Busy as Dust Storm Rages on Mars, Snaps Selfie

NASA / JPL-Caltech / MSSS / Seán Doran

A Radioisotope Thermoelectric Generator means NASA’s Curiosity rover always stays busy, dust or shine. Not even an intense dust storm can keep the rover down. While the Opportunity rover had to shut down, the folks responsible for Curiosity are still doing science.

Curiosity even had time to capture a selfie.

The composite image put together by Seán Doran shows what Curiosity and its dusty surroundings looked like on Sol 2082 (the date on Mars since Curiosity landed). Today is Sol 2086.

Despite looking like a single frame, the image is stitched together from many images captured by the Mars Hand Lens Imager, or MAHLI, mounted on the rover’s robotic arm. Each time a picture is captured, the robotic arm is behind the camera’s view.