Scars on Mars fade … sometimes / Comet-cluster mashup

Curiosity descent and heat shield impact. Best heat shield images are at the end.

It’s only been a couple years, but the blast marks left by the descent stage that delivered the Curiosity rover to Mars as well as it heat shield that protected it have changed markedly in appearance. But not exactly the way you’d think.

This sequence of images shows a blast zone where the sky crane from NASA's Curiosity rover mission hit the ground after setting the rover down in August 2012, and how that dark scar's appearance changed over the subsequent 30 months. Image Credit: NASA/JPL-Caltech/Univ. of Arizona

This sequence of images shows a blast zone where the sky crane from NASA’s Curiosity rover mission hit the ground after setting the rover down in August 2012, and how that dark scar’s appearance changed over the past 30 months. Credit: NASA/JPL-Caltech/Univ. of Arizona

Curiosity was carefully lowered to the Martian surface in August 2012 by a powered descent stage that blasted away bright Mars dust to expose darker material beneath. Shortly before it landed, the probe ejected its heat shield which slammed into the crust some distance away. Once Curiosity landed, the descent stage or sky crane shot away and crash landed as well. Since that time, the winds crisscrossing the Red Planet have gradually re-coated the darkened areas with bright dust.

sequence shows where the rover itself landed. Curiosity disappears after the first two of the seven frames because it drove away. Its wheel tracks heading generally east (toward the left) can be seen in subsequent frames, and they also fade over time. Credit: NASA/JPL

sequence shows where the rover itself landed. Curiosity disappears after the first two of the seven frames because it drove away. Its wheel tracks heading generally east (toward the left) can be seen in subsequent frames, and they also fade over time. Credit: NASA/JPL

You might assume that accumulating dust would erase the scars, and this was true at first. Lately however, the process appears to have reversed itself.

“We expected to see them fade as the wind moved the dust around during the months and years after landing, but we’ve been surprised to see that the rate of change doesn’t appear to be consistent,” said Ingrid Daubar, a HiRISE camera team scientist at NASA’s Jet Propulsion Laboratory who studied images of the blemishes taken by the Mars Reconnaissance Orbiter.

After fading for two years, the rate of change slowed with some areas re-darkening. Scientists are repeatedly checking the blast zones to compare their models against reality, revealing that we still don’ t fully understand how Martian dust is transported around the planet.

MarsBlast Heat shield

Five-frame sequence of the location where the spacecraft’s heat shield hit the ground. Credit: NASA/JPL-Caltech/Univ. of Arizona

Daubar’s work on this aids preparations for NASA’s next Mars lander, InSight, expected to launch in March 2016. The InSight mission will deploy a heat probe that will hammer itself a few yards, or meters, deep into the ground to monitor heat coming from the interior of the planet.

The brightness of the ground affects temperature below ground, because a dark surface warms in sunshine more than a bright one does.

Comet Siding Spring cruises past the bright globular star cluster M92 in Hercules on March 29, 2015. Credit: Rolando Ligustri

Comet Siding Spring cruises past the bright globular star cluster M92 in Hercules on March 29, 2015. Credit: Rolando Ligustri

Now that you’re brain’s completely flickered out after viewing three animations, let me share one additional photo from the weekend that has a Mars connection. It shows the comet C/2013 A1 Siding Spring passing very close in a beautiful way to the globular cluster M92 in the constellation Hercules. Siding Spring swept so close to Mars last fall it created a meteor shower in the planet’s atmosphere. Now it’s juxtaposed again, this time in the foreground of a star cluster that’s 26,700 light years from Earth.

Mars Opportunity rover falters, may be on the chopping block

Surprise landing! On January 25, 2004 the airbag-cushioned lander carrying the Opportunity rover came to rest smack in the middle of Eagle Crater. Mars Reconnaissance Orbiter photo colorized by the author. Credit: NASA/JPL-Caltech

If you have a digital camera you’re familiar with reformatting your memory card after you’ve filled it up and downloaded your images. Reformatting clears the card and allows you to write to it again. But after maybe a hundred of these digital lobotomies a card will often begin to malfunction. Now unreliable, it can’t be trusted, so you toss it and pop in a fresh one.

After climbing out of Eagle Crater, Opportunity looked back to photograph the lander. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

NASA’s now in the same situation with the flash memory drive in the Mars rover Opportunity. The drive, which stores data when the rover “sleeps” at night, is wearing out after more than 11 years on the Red Planet. As with any camera memory card there are limits to how many times you can write to and erase data.

Over the past six months NASA has had difficulties getting the rover to store commands sent from Earth. Commands, data and photos are normally stored in Opportunity flash memory or hard drive. But the rover’s has lately taken to moving some of that information into its “volatile” or RAM (random access memory) like that found in your computer.

The Opportunity Mars rover took this mosaic self-portrait in March 2014. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

When you shut down your computer, the important stuff remains on the hard drive while all the temporary settings or RAM memory’s erased. But when Opportunity powers down at night, commands and data that shouldn’t have been moved to RAM are deleted along with all the temporary stuff.

Before Christmas, mission control sent three days’ worth of commands to the rover, but memory troubles meant that only the one day’s activities were kept and completed.

Since the trouble began, the mission’s operations team has been avoiding using the flash system and is currently working on a software fix. In the meantime, they’ve been downloading everything into RAM memory every day before the rover’s nightly shuteye.

Opportunity explored the interior of Victoria Crater back in 2007-2008. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

That might not be the end of Opportunity’s woes. There’s no money in the proposed federal budget to fund the rover beyond the current budget year. Unless additional funding is found by NASA, Opportunity will bite the Martian dust sometime this fall.

The agency has the difficult task of deciding how to divide a limited amount of money between new missions and continuing to fund old ones.

Opportunity landed on Mars on January 25, 2004 and was only designed to operate for 90 days. The rover is presently sniffing around on the west rim of Endeavour Crater heading towards “Marathon Valley,” where abundant clay minerals may lie just about 984 feet (300-m) away from its present position. Then it’s off to the “Spirit of St. Louis” crater.

The aptly-named Cape Tribulation along a segment of the rim of Endeavour Crater which the rover reached in early January. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Opportunity has truly run a marathon in its 11-plus years with 26 miles of roving to its credit, the farthest any machine has driven on the surface of another world besides Earth. It snatched the record last July from the former Soviet Union’s remote controlled Lunokhod 2 rover, which ambled across 24.2 miles (39 km) of the moon back in 1973.

Gosh, it’s bleak on Mars. Photo taken by Opportunity yesterday February 3, 2015. Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

So yes, Opportunity has outlived its original design lifetime more than 44 times over. And yes, it’s starting to lose its nimble mind, but I believe the relatively small amount of money (its 2014 budget was $14 million) it would take to keep it going another year or two is well worth it if only because of the potential for additional discoveries and opportunities. Remember, only Opportunity got a decent photo of Comet Siding Spring when it passed close to Mars last fall. Once it’s shutdown, the only feet on Martian ground will be the Curiosity rover’s.

Spectacular meteor storm lights up Mars during recent comet flyby

On October 19, when Comet C/2013 A1 Siding Spring flew just 87,000 miles from Mars, dust from its tail set the sky aglow with a meteor storm. This illustration is my feeble attempt to show what you might have seen standing on Mars next to the Curiosity rover at the time. Credit: NASA (background) with additions and changes by Bob King

Oh, to have stood under the Martian sky on October 19th! As Comet Siding Spring passed just 87,000 miles (140,000 km) from the planet that night, dust in its tail slammed into the Martian atmosphere at 126,000 mph, burning up in storm of meteoric madness. “Thousands per hour fell,” said Nick Schneider, instrument lead for NASA’s MAVEN Imaging Ultraviolet Spectrograph. It must have looked like those classic illustrations of the 1833 and 1866 Leonid meteor storm back here on Earth.

Composite image of Comet Siding Spring and Mars taken by the Hubble Space Telescope. The images have been added together to create a single picture to illustrate the true distance or separation (1/20th the apparent size of the Full Moon) between the comet and Mars at closest approach.  Credit: NASA/ESA

I participated in a teleconference yesterday with principal investigators for the instruments on the Mars Reconnaissance Orbiter (MRO), MAVEN and Mars Express spacecraft pressed into service to study Comet Siding Spring during its historic flyby. The comet is a visitor from the faraway Oort Cloud, a spherical repository of billions of icy comets up to 1 light year from the Sun. Some 4-5 Oort Cloud comets swing through the inner solar system every year; this is the first one we’ve ever studied up close. It was discovered at Siding Spring Observatory in Australia by Robert McNaught on January 13, 2013.

NASA’s MAVEN uses its IUVS to perform a scan of the Martian atmosphere along its limb. Scans found enhanced levels of metals from vaporizing comet dust. Credit: NASA

“Dust slammed into the atmosphere and changed the chemistry of the upper atmosphere,” said Jim Green, director, Planetary Science Division, NASA Headquarters in Washington. Data from MAVEN’s UltraViolet Spectrograph (IUVS), which scans of Mars’ upper atmosphere in UV light to determine its chemical makeup, saw big spikes in the amount of magnesium and iron during the flyby. These elements are commonly found in meteorites.

Before and after scans by MAVEN. At left is a profile of the atmosphere before the comet’s arrival showing carbon dioxide and other gases; at right is during the comet’s pass. Check out that huge spike to the right – that from magnesium. Elevated levels to the left indicate iron. Credit: NASA

Siding Spring turned out to be much dustier than expected, prompting Green to later add: “It makes me very happy hid them (spacecraft) on the backside of Mars.” “It really saved them. Even one well-placed hit from a high-speed dust particle could damage an instrument, and Siding Spring peppered the Martian atmosphere with “several tons” of dust.

MAVEN used its mass spectrometer – an instrument that identifies elements by how much mass they have – to record a big enhancement of the elements magnesium, manganese, iron and others from comet dust in Mars’ atmosphere. Credit: NASA

Meanwhile, MAVEN’s Neutral Gas and Ion Mass Spectrometer (NGIMS), picked up major spikes in 8 different metals from ablating comet dust including sodium, magnesium, iron and nickel. Jim Green pointed out that the increase in sodium may have tinged the twilight sky with a yellow glow. That and a recent increase in the amount of dust in the atmosphere over the Curiosity rover site may be the reason the comet was so difficult to photograph from the ground.

Only hours after Comet Siding Spring’s closest approach, dust particles hitting air molecules on Mars formed a temporary ionized (electrified) layer in its lower ionosphere 50-60 miles high. Credit: ESA

So we have a very dusty comet, a big meteor storm, the atmosphere spiced up with metals from burning dust.

Anything else? Heck, yes. The European Space Agency’s Mars Express Orbiter used its radar to send out radio waves of very low frequency down through Mars atmosphere to record the state of the ionosphere, a rarified layer of air between 60-250 miles (100-400 km) high. At the comet’s closest approach, the ionosphere was normal, but 7 hours later, impacting dust had created a brand new, temporary ionization layer.

Close-ups pictures taken by the Mars Reconnaissance Orbiter of Comet Siding Spring around the time of closest approach to Mars. They show the combined light of the tiny nucleus and much larger coma or comet atmosphere. Comet dust / rocks range in size from 1/1000 of a millimeter to 1 centimeter (~1/2-inch). Credit: NASA

The high resolution camera on the MRO photographed brightness variations in the comet’s light, nailing down its rotation period to 8 hours. But size-wise, we’re a little less clear. Estimates for the comet’s nucleus range from 984 feet to 1.2 miles (300-m to 2 km). For comparison, Comet 67P/Churyumov-Gerasimenko, currently orbited by Europe’s Rosetta spacecraft, is 1.5 miles (2.4 km) across.

Color variations in this photo by CRISM indicate different sized dust particles being ejected by the comet. Credit: NASA

Yet another instrument named CRISM (Compact Reconnaissance Spectrometer for Mars) made some intriguing measurements of the coma showing distinct differences in color – red here, blue there – indicating the comet is blowing out dust particles of different sizes.

As scientists continue to analyze the data collected by the fleet of space probes, we’ll see more papers and results soon. For now, the rare opportunity to study a comet up close from another planet was an unqualified success. You can listen to the replay of the hour-long conference HERE.

Earth and Moon captured together in amazing new photo

Chang’e 5 took this splendid photo of Earth and Moon together while it passed over the lunar far side on October 28, 2014. The Moon reflects far less light than Earth and appears darker.  Click to grab a large version. Credit: CNSA / Xinhua News Agency

A friend alerted me to this wonderful photo of Earth and Moon in the same single image taken by China’s Chang’e 5 lunar test vehicle. The spacecraft is conducting an 8-day mission to the Moon and back to refine the technology needed for a planned sample return mission in 2017. Launched on October 23, this is China’s fourth volley to the Moon; the spacecraft will return to Earth on November 1 according to Xinhua News.

View of Earth taken by the Chang’e 5 test vehicle on October 28 after rounding the far side of the Moon. Australia is easy to see in the clearing. Credit: CNSA / Xinhua News Agency

As it swung high above the far side of the Moon – the hidden half of the lunar globe out of sight from Earth – the solar array monitoring camera on the craft snapped this incredible image. While not the first ever taken of the pair, it’s one of the best composed images and possibly the first to clearly feature the lunar far side along with Earth. You can easily see how much more cratered the Moon’s hidden hemisphere is. And that dark splotch? That’s Mare Moscoviense (Sea of Moscow), one of the very few dark maria or seas on the far side.

View of the Moon by Chang’e 5 on October 28 shows the dark lunar “sea” called Mare Marginis. This patch is visible along the western edge of the moon from Earth. Credit: CNSA / Xinhua News Agency

Chang’e 5 did not enter lunar orbit but kept its camera humming to shoot separate close-ups of Earth and Moon. Like seeing Earth and Moon from afar? Check these out:

Earth and Moon dance a pirouette in these images taken by the Jupiter-bound spacecraft Juno on Oct. 9, 2013

The European Space Agency’s Mars Express captured this image of Earth and the Moon on July 3, 2005 when it was 5 million miles ( 8 million km) away. Credit: ESA

Earth and Moon in 1992 as Galileo photographed the duo on its way to Jupiter. Credit: NASA

Earth is the brightest “star” in Mars’ western evening sky as seen and photographed by the Curiosity Rover on Jan. 31, 2014. Credit: NASA

A single frame from high-definition video of the full Earth over the lunar limb taken by Japan’s Kaguya spacecraft on April 6, 2008. Credit: JAXA/NHK

Earth and Moon from Mars, imaged by Mars Global Surveyor on May 8, 2003. Credit: NASA

Earth rises over the barren lunar landscape photographed by the Apollo 8 crew on December 24, 1968. Credit: NASA

Earth and Moon become a single dot in this photo taken by the Voyager 1 spacecraft from a distance of 4 billion miles (6.4 billion km) on February 14, 1990. Credit: NASA/JPL

What’s that musket ball doing on Mars?

Certainly catches the eye, doesn’t it? The spherical rock was photographed on September 11, 2014 by the Curiosity rover. It’s about a half-inch across and according to NASA scientists probably a concretion. Credit: NASA/JPL-Caltech/MSSS

It looks ever so much like an early 18th century musket ball, but the chances of soldiers traipsing around Mars a couple hundred years ago seems unlikely. Even if it’s the god of war. NASA’s Curiosity rover snapped this photo during a routine round of landscape imaging on September 11th.

There’s nothing like seeing a near-perfect sphere on another planet to make you sit up and wonder. First off, it’s not as big as you might think, measuring just under 1/2 (1 cm) in diameter or about the size of a marble. Second, we’ve seen spheres on Mars before – zillions of them!

Tiny “blueberries” in the Martian soil near the rock outcrop at Meridiani Planum called Stone Mountain. While other ideas have been proposed for their formation, water trickling through rocks to build concretions remains a strong possibility. Credit: NASA/JPL

The Mars Opportunity rover found countless spheres, nicknamed Martian “blueberries”, during  its exploration of Meridiani Planum. If you could hunker down for a look, they’d remind you of BBs from a  BB gun with diameters of .16 to .24 inches (4-6 mm). The spheres contain large amounts of hematite, an iron-bearing mineral, that most likely originated as concretions in layers of sedimentary rock that have since eroded away.

Groundwater moving through porous rocks can dissolve iron-containing minerals which then precipitate out as small, compact spheres. Concretions on Earth, such as Moqui balls and Kansas Pop Rocks, are considerably larger than the Martian variety, but that may be due to the different environments of the two planets. 

So our mystery sphere is probably a larger-than-usual concretion, freed from its rock stratum by wind and perhaps water erosion and now served up on a plate for Curiosity’s and eyes.

To view more pictures of the weird sphere, click HERE and scroll down toward the bottom for the Mastcam color images.

Planets, moon gather at dusk / Curiosity chews into Mt. Sharp

The crescent moon and Saturn twist the night away this evening September 27, 2014. Catch the pair low in the southwestern sky 1-2 hours after sunset. Further east, Mars joins Antares in conjunction. Stellarium

Space weather experts are forecasting a minor G1 geomagnetic storm with possible auroras across the northern U.S. and southern Canada this evening.

While you’re out watching for that telltale green arc in the north, take a few minutes to face the opposite direction. Low above the southwestern horizon you’ll find the crescent moon parked near the planet Saturn. It may be our last chance to see the planet with ease. Saturn’s been sinking into the west for some time. Tonight’s moon will guide you right to it.

A little more than a fist to the left or east of Saturn, Mars will be in conjunction with its colorful friend Antares (both are red-hued) only 3.1º to its north. Both star and planet shine at magnitude +1 though Mars is officially a hair brighter. Can you see the difference?

Photo from the Mars Hand Lens Imager (MAHLI) camera on Curiosity shows the first sample-collection hole drilled in Mount Sharp, the layered mountain that is the science destination of the rover’s extended mission. The hole is 0.63 inch wide and about 2.6 inches deep and photographed from 2 inches away. Click to enlarge. Credit: NASA/JPL-Caltech

This week NASA’s Mars Curiosity Rover drilled and gathered its first rock sample from the base of Mt. Sharp in Gale Crater. The target rock formation, called Confidence Hills, lies on the Pahrump Hills outcrop at the base of the mountain. The rock is a mudstone and softer than any of the rocks previously sampled by the rover.

Mudstone rock outcrop where Curiosity got its first taste of Mt. Sharp (drill hole at top), the rover’s main science target during its time on Mars. Curiosity landed on the planet in August 2012. Credit: NASA/ JPL-Caltech, colorized by Bob King

“This drilling target is at the lowest part of the base layer of the mountain, and from here we plan to examine the higher, younger layers exposed in the nearby hills,” said Curiosity Deputy Project Scientist Ashwin Vasavada of JPL. Scientists hope to get a look at the first rock to underlie Mount Sharp to get a picture of the environment at the time the mountain formed and what led to its formation. Mount Sharp is composed of layered sediments, some of which appear to have been deposited by water several billion years ago.

Fish-eye view taken with Curiosity’s front hazcam showing the drill at work on the Confidence Hills target at the base of Mount Sharp September 24, 2014. The rock surface is webbed with cracks. Click to enlarge. Credit: NASA/JPL-Caltech, colorized by Bob King

NASA will put the breaks on Curiosity now that it’s reached its prime science destination after traveling 5 miles (8 km) since touching down on Mars August 6, 2012. Next, the rover will deliver a powdered rock sample into a scoop on it arm, where the soil’s texture will be scrutinized to access whether it’s safe for further sieving, portioning and delivery into Curiosity’s internal laboratory instruments without clogging hardware.


Drum roll please … Curiosity takes first-ever pix of asteroids from Mars!

The Curiosity rover captured the first image of asteroids from the surface of Mars. Also included in the image are separate photos of Mars’ moon Deimos in a circular, exposure-adjusted inset and square insets at left from other images the same night of its second moon Phobos as well as Jupiter and Saturn. Credit: NASA/JPL-Caltech/MSSS/Texas A&M

Dang! NASA’s Curiosity rover beat me to it by just one day, spotting the asteroids Ceres and Vesta from the surface of Mars on Sunday April 20. Me? I caught them later that night from a comfortable location on Earth with a pair of 8×40 binoculars.

The rover aimed its high-resolution mast camera skyward to take the first-ever photos of the largest (Ceres) and brightest (Vesta) asteroids. Both objects are destinations of NASA’s Dawn Mission as we learned in this recent blog. The photo shows trailed images of both – it was a 12-second time exposure – and Mars’ smaller moon Deimos. The others were added to make a composite. While it looks like it was taken with a mobile phone, it’s one of very few photos taken of the night sky from another planet.

Original mastcam photo of Ceres, Vesta and much brighter Deimos, the smaller of Mars’ two moons. Credit: NASA

The two asteroids and three stars would be visible to someone of normal eyesight standing on Mars. Specks are effects of cosmic rays striking the camera’s light detector. Given that Mars is located closer to the asteroid belt than Earth, I checked the brightness of Ceres and Vesta. Interestingly, both are located in the constellation Virgo just as they are from our own planet right now, but their brightnesses differ. Vesta shines at magnitude +4 (+5.8 from Earth), making it a relatively easy naked eye object from the Martian ‘countryside’. Ceres is currently magnitude +7 from home but magnitude +5.8 and dimly visible with the naked eye from Mars.

Thinking about it a minute, it shouldn’t surprise us that both asteroids are traveling together in the same constellation as seen from both planets. Can you guess why? Remember that Mars was at opposition earlier this month and lined up with Earth on the same side of the sun. That alignment means that we both look out at virtually the same “springtime” constellations in our respective night skies AND look in nearly the same direction when viewing Ceres and Vesta. If Mars was on the opposite side of the sun, Martians would have to look in the opposite direction of the sky to see them.

Curiousity took this fisheye photo with its front hazcam on April 24, 2014 from the Kimberley showing one of the three hills, likely Mt. Remarkable. Credit: NASA/JPL-Caltech

“This imaging was part of an experiment checking the opacity of the atmosphere at night in Curiosity’s location on Mars, where water-ice clouds and hazes develop during this season,” said camera team member Mark Lemmon of Texas A&M University, College Station. “The two Martian moons were the main targets that night, but we chose a time when one of the moons was near Ceres and Vesta in the sky.”

We love it and wouldn’t complain if you guys shot more nighttime stuff. How about a sequence of images of the rising Earth or a longer time exposure showing star trails with the landscape faintly illuminated by the light of Phobos and Deimos?

Curiosity rover revels in ravishing rocks at ‘the Kimberley’

A view of Curiosity’s new digs called ‘the Kimberley’, named for a wilderness region in Western Australia. Taken on April 11 it shows tilted sandstones separated by windblown sands. The hilly rim of Gale Crater is seen in the distance. Click to enlarge. Credit: NASA/JPL-Caltech

NASA’s one-ton Curiosity rover has beamed back thousands of photos of amazing landscapes within Gale Crater since landing in August 2012. And that’s after driving only 3.8 miles, probably the distance to the nearest grocery store for many of us.

The Kimberley seen from orbit with the rover’s path highlighted. Curiosity rolled into the new location around the 589th Martian day or “sol”. Scientists selected the area based on pictures and studies made from orbit showing it to be rich in different rock types all exposed in the same location. Credit: NASA/JPL-Caltech

Earlier this month, the rover entered the Kimberley, a rise within the crater dotted with three buttes – Mounts Remarkable, Joseph and Christine – that exposes several varieties of rock scientists are eager to study. The area will be the focus of exploration for weeks to come before Curiosity resumes its journey to the slopes of Mount Sharp, a broad peak that rises 3 miles (5 km) from the crater’s floor.

Sandstones on Mars near the Kimberley photographed on March 29, 2014. Click to enlarge. Credit: NASA/JPL-Caltech

The Kimberley is strewn with some of the most beautiful sandstones yet seen on Mars. Sandstones form when water or wind carries along grains of sand until depositing them in a layer at the bottom of a stream or on the ground as in a desert. Minerals within the pore spaces between the sand grains cement the grains together to create sandstone. Sometimes layers of deposited sand can build up one atop another helping to further compact the material into stone.

Differing degrees of resistance to erosion result in a stair-stepped pattern visible in this photo taken 1/4 mile northwest of the Kimberley on Feb. 25, 2014. Steeper steps result from more resistant rock, so the flat, tan surface (foreground) is a weakly resistant sandstone. The small steps to the right center are a bit more resistant, and the steeper steps near the top of the scene are even more resistant. Click to enlarge. Credit: NASA/JPL-Caltech/MSSS

Cement materials vary greatly. Clay minerals build sandstones that crumble with a rap of a hammer and more quickly erode in the Martian winds. Quartz cement creates a tougher rock more resistant to erosion. If you’ve ever marveled at the sight of a western, canyon-filled landscape, you’re seeing the varying resistance of sandstone to erosion at work. The same thing happens on Mars:

Another spectacular view of tipped and tilted sandstones with Mt. Remarkable in the distance photographed on April 11, 2014. Click to enlarge. Credit: NASA/JPL-Caltech

“A major issue for us now is to understand why some rocks resist erosion more than other rocks, especially when they are so close to each other and are both likely to be sandstones,” said Michael Malin of Malin Space Science Systems, San Diego. Malin added that variations in cement material of sandstones could provide clues to different types of wet environmental conditions in the area’s history.

Curious furrows are seen in the foreground in this photo taken at the Kimberley on April 3, 2014. Click to enlarge. Credit: NASA/JPL-Caltech/MSSS

At Yellowknife Bay, Curiosity’s last major waypoint, erosion had exposed both sandstones and a lower layer of mudstone that was once part of an ancient lake bottom. The rover will be tooling around the Kimberley for a while – why not join the exploration by periodically checking out the Mars raw image archive?

A conglomerate rock formation at the Kimberley formed of boulders and rocks that were transported from elsewhere – by river or glacier for instance – and cemented together. Click to enlarge. Credit: NASA/JPL-Caltech/ MSSS

Curiosity wheel tracks seen from orbit / How do you drive a rover anyway?

Two parallel tracks left by the wheels of NASA’s Curiosity Mars rover cross rugged ground in this photo taken on Dec. 11, 2013 from orbit. At the time, it had driven about 2.86 miles (4.61 km) since its August 2012 landing in Gale Crater. Click to enlarge. Credit: NASA/JPL-Caltech/Univ. of Arizona

Photos taken by the Curiosity rover’s cameras often leave the impression of a wide-open, easily navigable landscape. Sure there are plenty of rocks to avoid, but the way ahead toward Mt. Sharp looks clear, right? Maybe not so much once you get an orbital perspective.

Curiosity driver Jeng Yen. Credit: NASA

NASA recently released photos taken by the Mars Reconnaissance Orbiter showing Curiosity’s zigzagging tracks across surprisingly rugged, up-and-down terrain. The rover is slowly moving from a bright dust-covered area to a region with a darker surface, where windblown sand scours the surface relatively free of dust.

Studying the images I gained a new appreciation for the work done by the Jeng Yen and the team of Curiosity drivers.

Yen, who’s worked at the Jet Propulsion Lab since 1998, has successfully developed rover models and simulation methods used by the Spirit and Opportunity rovers during their explorations of Mars. He also pilots the Curiosity rover.

Driving a robot car remotely from a distance of 117 million miles resembles playing a video game but only after you’ve done a lot of homework. After mission scientists choose a target, Yen uses pictures taken by Curiosity along with an elevation map of the region created with data gathered from the Mars orbiter to plot a safe path to the target area.

NASA’s Curiosity Mars rover (lower left) and tracks left by its driving appear in this portion of a Dec. 11, 2013, observation by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter. The wheel tracks are about 10 feet (3 m) apart. Click to enlarge. Credit: NASA/JPL-Caltech/Univ. of Arizona

Next, he creates a drive sequence of various turns and moves to follow the plotted path and then simulates the path using special software. Finally, any potential obstacles are discovered – and avoided – by examining the route with stereo imagery.

View from Curiosity’s navigational camera on Jan. 8, 2014. The open landscape is deceptive. There are slopes and other obstacles for which detailed elevation data and 3D modeling are needed to navigate the terrain safely. Click to enlarge. Credit: NASA/JPL-Caltech

Then he does it all over again and makes his request from the science and engineering teams to move to the target. If approved, Yen gets comfortable and toggles Curiosity along its chosen way. Seeing the photos stream back to Earth is the favorite part of his job.

Future Mars rover drivers? The Duluth East robotics team pilot their robot named “Archie” to pick up inner tubes and place them on pegs during a competition. Credit: Bob King

While we can be sure there’s a lot of hard work involved, Yen and colleagues must enjoy the immense satisfaction of exploring another planet in real time. With the tremendous surge recently in high school robotics programs and competitions, a career goal of becoming a rover driver on Mars or the moon can’t help but inspire.

Note: Source for information on Jeng Yen’s rover piloting skills HERE.


Mars a tough place for a country drive – Curiosity’s wheels look like heck

Close up of one of Curiosity’s wheels photographed on Dec. 22 shows plenty of dings, small holes and one big tear. Click to see the damage up close. Credit: NASA/JPL-Caltech/MSSS

More than a year’s worth of puttering around on Mars has done a number on the Curiosity rover’s six aluminum wheels. Look at all those dings, pits and holes.

Would you drive your car on this? View of Curiosity’s surroundings on Dec. 20, 2013. Credit: NASA/JPL-Caltech/MSSS

“Dents and holes were anticipated,” said Jim Erickson, project manager for the NASA Mars Science Laboratory Project, which operates Curiosity,” but the amount of wear appears to have accelerated in the past month or so. It appears to be correlated with driving over rougher terrain. The wheels can sustain significant damage without impairing the rover’s ability to drive.”

To that end, the project team is looking toward minimizing the amount of driving Curiosity will do over rugged terrain. Its recent travels have taken it over numerous sharp rocks embedded in the Martian soil as it tracks toward Gale Crater’s central peak Mt. Sharp.

Engineers ready Curiosity – and its brand new set of aluminum wheels – before launch last year. Credit: NASA

Curiosity’s wheels are 19.6 inches (50 cm) in diameter or bigger than a car tire and each has its own motor, making the rover a full-fledged “six-wheel drive” vehicle that can get itself out of many a tight spot. The rover can even do a full 360-degree turn in place. About the only thing the engineers didn’t consider was a spare.