Opportunity's shadow aims eastward to the rim of Endeavour crater
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The rover Opportunity captured a view into Endeavour crater as a low Sun cast a long shadow in this image, acquired back on March 9.
Endeavour is a large crater — 14 miles (22 km) wide, it’s about the same area as the city of Seattle. Opportunity arrived at its edge in August of 2011 after several years of driving across the Meridiani Plains.
Opportunity is currently the only operational manmade object on the surface of Mars… or any other planet besides Earth, for that matter. It’s a distinction it will hold until the arrival of Mars Science Laboratory at Gale Crater this August.
The scene is presented in false color to emphasize differences in materials such as dark dunes on the crater floor. This gives portions of the image an aqua tint.
Opportunity took most of the component images on March 9, 2012, while the solar-powered rover was spending several weeks at one location to preserve energy during the Martian winter. It has since resumed driving and is currently investigating a patch of windblown Martian dust near its winter haven.
Opportunity and its rover twin, Spirit, completed their three-month prime missions on Mars in April 2004. Both rovers continued for years of bonus, extended missions. Both have made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life. Spirit stopped communicating in 2010. Since landing in the Meridiani region of Mars in January 2004, Opportunity has driven 21.4 miles (34.4 kilometers).
Image credit: NASA/JPL-Caltech/Cornell/Arizona State University
Opportunity's traverse map from Sol 2951 (May 13 on Earth) and shows the entirety of the rover's travels to that point. Image Credit: NASA/JPL/Cornell/University of Arizona
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After spending 19 weeks working in one place during the Martian winter in Meridian Planum, the Opportunity Mars rover is now roving once again. During the winter, available solar power was too low for driving, but on May 8th (here on Earth), Opportunity took its first drive since Dec. 26, 2011. She drove about 3.67 meters (12 feet) northwest and downhill.
“We’re off the Greeley Haven outcrop onto the sand just below it,” said rover driver Ashley Stroupe of JPL. “It feels good to be on the move again.”
During the period while the rover was stationary, she wasn’t just sleeping. Engineers sent commands for Oppy to use the spectrometers and microscopic imager on its robotic arm to inspect more than a dozen targets within reach on the outcrop. Radio Doppler signals from the stationary rover during the winter months served an investigation of the interior of Mars by providing precise information about the planet’s rotation, a study that scientists were hoping to do with the Spirit rover, but unfortunately she fell silent before they could do the experiment.
Opportunity drove about 12 feet (3.67 meters) on May 8, 2012, after spending 19 weeks working in one place while solar power was too low for driving during the Martian winter. The winter worksite was on the north slope of an outcrop called Greeley Haven. The rover used its rear hazard-avoidance camera after nearly completing the May 8 drive, capturing this view looking back at the Greeley Haven. The dark shape in the foreground is the shadow of Opportunity's solar array. The view is toward the southeast. Image Credit: NASA/JPL-Caltech
So how is Opportunity’s power supply? As long as the rover stays tilted northward towards the Sun – about 8 degrees is all that’s needed – she will have sufficient power to take short drives.
But unless wind removes some dust from her solar arrays, allowing more sunlight to reach the solar cells, the rover will need to work during the next few weeks at locations with no southward slope. “We’ll head south as soon as power levels are adequate to handle the slopes where we’ll go,” said Mars Exploration Rover Deputy Project Scientist Diana Blaney of JPL.
“Our next goal is a few meters farther north on Cape York, at a bright-looking patch of what may be dust,” said Opportunity science-team member Matt Golombek of JPL. “We haven’t been able to see much dust in Meridiani. This could be a chance to learn more about it.”
Beyond the dust patch, the team intends to use Opportunity to study veins in bedrock around the northern edge of Cape York. A vein inspected before winter contained gypsum deposited long ago by mineral-laden water flowing through a crack in the rock.
As you remember, Opportunity has been going strong for over 9 years now, exploring the Meridiani region of Mars since landing in January 2004. It arrived at the Cape York section of the rim of Endeavour Crater in August 2011, and has been studying rock and soil targets on Cape York since then.
The transition between Acidalia Planitia and Tempe Terra from the Mars Express High-Resolution Stereo Camera (HRSC). Credit ESA/DLR/FU Berlin (G. Neukum)
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ESA’s Mars Express orbiter has sent back images revealing terrain that seems to have been sculpted by flowing water, lending further support to the hypothesis that Mars had liquid water on its surface at some point.
The region seen above in a HRSC image is along the border of the Acidalia Planitia region, a vast, dark swath of Mars’ northern hemisphere so large that it’s visible from Earth.
In 1877 the Italian astronomer Giovanni Schiaparelli named the region after a mythical fountain, where the three Graces of Greek mythology were said to have bathed.
Although there may not be any fountains or ancient Immortals within Acidalia Planitia, there may have been water — enough to carve serpentine channels and steep scallops along the edges of wide valleys, much in the same way that the Grand Canyon was carved by the Colorado River.
In the HRSC image some of the etched valleys extend outwards from craters, implying that they were created by water emptying out from within the craters. In addition, sediments present within older craters indicate that they were once filled with water, likely for an extended time.
Acidalia Planitia in a broader context. (NASA MGS MOLA Science Team)
With images like these, so reminiscent of similar features found here on Earth, it’s hard to discount that Mars once had liquid water upon its surface; perhaps some of it still remains today in pockets beneath the ground!
Cooling lava on Mars can form patterns like snail shells when the lava is pulled in two directions at once. Such patterns, rare on Earth, have never before been seen on Mars. This image, with more than a dozen lava coils visible, shows an area in a volcanic region named Cerberus Palus that is about 500 meters (1640 feet) wide. Credit: NASA
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Strange coiling spiral patterns have been found on Mars surface by a graduate student who was doing what many of us enjoy: looking through the high-resolution images from the HiRISE camera on the Mars Reconnaissance Orbiter. Similar features have been seen on Earth, but this is the first time they have been identified on Mars. However, on Mars, these features, called lava coils, are supersized. “On Mars the largest lava coil is 30 meters across – that’s 100 feet,” said Andrew Ryan from Arizona State University. “That’s bigger than any known lava coils on Earth.”
The lava coils resemble snail or nautilus shells. Ryan has found about 269 of these lava coils just in one region on Mars, Cerberus Palus. 174 of them swirl in a clockwise-in orientation, 43 are counterclockwise, and 52 of the features remain unclassified due to resolution limits.
A small lava coil on pahoehoe flow, Kilauea Volcano, Hawai`i(see the pocket knife for scale.) Credit: W.W. Chadwick
On Earth, lava coils can be found on the Big Island of Hawaii, mainly on the surface of ropey pahoehoe lava flows. They usually form along slow-moving shear zones in a flow; for example, along the margins of a small channel, and the direction of the flow can be determined from a lava coil.
“The coils form on flows where there’s a shear stress – where flows move past each other at different speeds or in different directions,” said Ryan. “Pieces of rubbery and plastic lava crust can either be peeled away and physically coiled up – or wrinkles in the lava’s thin crust can be twisted around.”
Similarly, Ryan said scientists have documented the formation of rotated pieces of oceanic crust at mid-ocean ridge spreading centers.
Newer lava lying between two older plates of rough, hardened lava was still hot and plastic enough to form coils and spirals when the plates slid past one another. This image shows an area about 360 meters (1200 feet) wide in Cerberus Palus. Credit: NASA
But Ryan and the co-author on the paper, Phil Christiansen, Principal Investigator for the Thermal Emission Imaging Spectrometer on the Mars Odyssey spacecraft, are certain water has nothing to do with the formation of the lava coils on Mars.
“There are no known mechanisms to naturally produce spiral patterns in ice-rich environments on the scale and frequency observed in this area,” they wrote in their paper. “It is also unlikely that ice-rich patterned regolith, which takes decades to centuries to develop, could fracture and drift. The lava coils and drifting polygonal and platy-ridge lava crust described above are therefore most consistent with known volcanic analogs, rather than ice-related processes.”
These features are probably quite young, formed 1.5 to 200 million years ago in Mars’ late Amazonian period when the planet was volcanically active.
Proof that Mars is an ever-changing world: a view from the Mars Reconnaissance Orbiter in 2010 showed tracks from a rolling boulder; in an image of the same region 1 Mars year later the tracks have dissapeared. Credit: NASA/JPL/University of Arizona
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More proof that Mars is an ever-changing world: In 2010, the Mars Reconnaissance Orbiter’s HiRISE camera spotted evidence that a boulder had rolled down an incline in a crater. The boulder left a visible track in the Martian regolith big enough to be spotted by MRO. But just one Martian year later, the tracks are gone, erased from existence.
“This is most likely due to the fine bright dust that is transported in the atmosphere falling down and re-covering the dark markings,” wrote Ross A. Beyer on the HiRISE site.
Beyer said the boulder tracks are much darker because as the boulders roll “they set off miniature dust avalanches. The bright, fine dust slides away, leaving a darker, larger grained dust underneath.”
How do boulders start moving on Mars? The boulders were disturbed in some way, breaking them loose from the crater edge, and there are two different possibilities. One, is that a meteorite impact or other tremor shook the boulder loose. Another possibility, as in the case of avalanches MRO has seen on Mars, the spring thawing of frozen carbon dioxide which forms during the Martian winter can cause rocks and debris to break loose from a cliff or incline.
Mars is certainly not the dead world we once thought it was, and the power of HiRISE keeps revealing a changing, unpredicatable landscape.
After NASA was forced to back out the joint ExoMars mission with the European Space Agency due to budget constraints, ESA went looking for help with the planned multi-vehicle Mars mission. Now, reportedly the Head of Roscosmos Vladimir Popovkin met with Director General of the ESA, Jean-Jacques Dordain last week, and the two signed a memorandum of understanding to work together to make ExoMars a reality.
“The sides consider this project feasible and promising,” Popovkin’s spokeswoman Anna Vedishcheva was quoted in Ria Novosti. “The sides are to sign the deal by year-end.”
Russia’s participation in the project was also approved by the space council of the Russian Academy of Sciences.
The ExoMars program was slated to send an orbiter to Mars in 2016 and a rover in 2018, but after NASA pulled out of its part of the bargain — of providing several science instruments and an Atlas launch vehicle – ESA knew they could not do the entire mission on their own. Last fall, when it was becoming apparent that NASA’s ability to participate was in jeopardy, Dordain extended an invitation to Russia, and in turn Roscosmos officials hinted they might be interested in joining, offering to provide the use of their Proton rockets for the launches. The two space agencies then had preliminary talks at the Ariane 5 launch at Kourou, French Guiana in March, 2012.
Russian space agency chief Vladimir Popovkin said that Russia’s financing of ExoMars could be partially covered by insurance payments of 1.2 billion rubles (about $40.7 million) for the lost Phobos-Grunt sample return mission that would have gone to the Martian moon Phobos.
Artist concept of the ExoMars/Trace Gas Orbiter mission. Credit: NASA
The details of the new ExoMars partnership are yet to be worked out, but the ESA/NASA partnership would have sent the Trace Gas Orbiter to the Red Planet in 2016 to search for atmospheric methane — a potential signature for microbial life – as well as an advanced astrobiology rover to drill into the surface in 2018, with the hopes of determining if life ever evolved on Mars.
Unsurprisingly, the potential deal with Russia comes as a huge relief to European space scientists who have spent years working on ExoMars. Journalist Paul Sutherland quoted UK scientist John Zarnecki of the Open University, as saying, “It looks like the cavalry has come riding over the horizon to save us, but this time they are dressed in Russian uniforms. There will be a lot scientists in universities and research institutes throughout Europe who will be very relieved to hear this news. Otherwise it seemed that several years work preparing instruments for this mission was going to go down the drain.”
The folk at JPL have kindly put together an animation of the gigantic Martian dust devil spotted by the Mars Reconnaissance Orbiter. The dust devil is roughly 20 kilometers (12 miles) high, churning through the Amazonis Planitia region of northern Mars, and this shows what the tall but thin dust devil would look like if you were observing it as you hovered around in your Mars helicopter or balloon.
Computer-generated perspective of the Tractus Catene pit chains. Credit: ESA/DLR/FU Berlin (G. Neukum)
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Recent images from ESA’s Mars Express spacecraft reveal long rows of crater-like depressions lining the flanks of ancient Martian volcanoes located in the planet’s vast Tharsis region. Rather than being the result of impact events, these “pit chains” were likely caused by underground lava flows — and could be a prime location for look for life.
Like similar features found on Earth, lava tubes on Mars are the result of rivers of magma that carved channels beneath the surface. When these channels empty out, a hollow tube is left. If the roof of a particularly large tube is near the surface the roof can eventually collapse, creating a surface depression… or, in some cases, opening up to the surface entirely.
Even though volcanism on Mars isn’t currently active — the last eruptions probably took place at least over a million years ago — the features left by volcanic activity are still very much present today and likely well-preserved beneath the Martian surface.
Shielded from harsh solar and cosmic radiation, the interior of such lava tubes could provide a safe haven for microbial life — especially if groundwater had found its way inside at some point.
Even though the surface of Mars can receive 250 times the radiation levels found on Earth, the layers of soil and rock surrounding the tubes can provide adequate protection for life, whether it be ancient Martian microbes or future explorers from Earth.
A wider image of the Tractus Catena region showing the large shield volcano Ascraeus Mons. Credits: ESA/DLR/FU Berlin (G. Neukum)
Of course, water and protection from radiation aren’t the only factors necessary for life. There also needs to be some source of heat. Fortunately, the pit chains imaged by Mars Express happen to be within one of the most volcano-laden areas of the Red Planet, a region called the Arcadia quadrangle. Within this area exist some of the largest volcanoes on Mars — and the Tractus Catena pits are located right in the middle of them.
If a heat source were ever to have been beneath the surface of Mars, there would be a good chance it would have been here.
And if our own planet is any measure of such things, where there’s heat and water there is often some form of life — however extreme the conditions may be.
“I’d like to see us land ON a volcano,” Dr. Tracy Gregg, a volcanologist with the University of Buffalo, had once told Universe Today back in 2004. “Right on the flanks. Often the best place to look for evidence of life on any planet is near volcanoes.”
“That may sound counterintuitive, but think about Yellowstone National Park , which really is nothing but a huge volcano,” Gregg elaborated. “Even when the weather in Wyoming is 20 below zero, all the geysers, which are fed by volcanic heat, are swarming with bacteria and all kinds of happy little things cruising around in the water. So, since we think that the necessary ingredients for life on Earth were water and heat, we are looking for the same things on Mars.”
As far as any remaining geothermal activity still happening beneath the Martian surface?
“I strongly suspect there are still molten (or at least mushy) magma bodies beneath the huge Tharsis volcanoes,” Gregg had said. (Read the full article here.)
On Earth, lava tubes, caves and underground spaces of all kinds harbor life, often specialized forms that are found no place else. Could this be (or have once been) the case on Mars as well? Only future exploration will tell. Until then, places like Tractus Catena will remain on scientists’ short list of places to look.
Last month, we were excited to share an image of a twister on Mars that lofted a twisting column of dust more than 800 meters (about a half a mile) high. We now know that’s nothin’ — just peanuts, chump change, hardly worth noticing. The Mars Reconnaissance Orbiter has now spotted a gigantic Martian dust devil roughly 20 kilometers (12 miles) high, churning through the Amazonis Planitia region of northern Mars. The HiRISE camera (High Resolution Imaging Science Experiment) captured the event on March 14, 2012. Scientists say that despite its height, the plume is just 70 meters (70 yards) wide.
Yikes! After seeing trucks thrown about by the tornadoes in Dallas yesterday, it makes you wonder how the MER rovers and even the Curiosity rover would fare in an encounter with a 20-km high twister.
The image was taken during late northern spring, two weeks short of the northern summer solstice, a time when the ground in the northern mid-latitudes is being heated most strongly by the sun.
Dust devils are spinning columns of air, made visible by the dust they pull off the ground. Unlike a tornado, a dust devil typically forms on a clear day when the ground is heated by the sun, warming the air just above the ground. As heated air near the surface rises quickly through a small pocket of cooler air above it, the air may begin to rotate, if conditions are just right.
Obviously, conditions were more than just right to create such a whopper.
Low Density Supersonic Decelerator prototype. Credit: NASA
Landing large payloads on Mars — large enough to bring humans to the Red Planet’s surface — is still beyond our capability. “There’s too much atmosphere on Mars to land heavy vehicles like we do on the moon, using propulsive technology completely,” said Rob Manning, Chief Engineer for the Mars Exploration Directorate, in an article we wrote a few years ago about the problems of landing on Mars “and there’s too little atmosphere to land like we do on Earth. Mars atmosphere provides an ugly, grey zone.”
The best hope on the horizon for making the human missions to Mars possible are supersonic decelerators that are now being developed. This new technology will hopefully be able to slow larger, heavier landers from the supersonic speeds of atmospheric entry to subsonic ground-approach speeds. NASA’s Low Density Supersonic Decelerator (LDSD) program is testing out some of these new devices and recently performed a trial run on a rocket sled test to replicate the forces a supersonic spacecraft would experience prior to landing. The sled tests will see how inflatable and parachute decelerators work to slow spacecraft prior to landing and allow NASA to increase landed payload masses, as well as improve landing accuracy and increase the altitude of safe landing-sites.
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Three devices are being developed: two different sizes of supersonic inflatable aerodynamic decelerators and super-huge parachutes. The supersonic inflatable decelerators are very large, durable, balloon-like pressure vessels that inflate around the entry vehicle and slow it from Mach 3.5 or greater to Mach 2. These decelerators are being developed in 6-meter-diameter and 9-meter-diameters.
The large parachute is 30 meters in diameter, and it will further slow the entry vehicle from Mach 2 to subsonic speeds. All three devices will be the largest of their kind ever flown at speeds several times greater than the speed of sound.
Together, these new drag devices can increase payload delivery to the surface of Mars from our current capability of 1.5 metric tons to 2 to 3 metric tons, depending on which inflatable decelerator is used in combination with the parachute. They will increase available landing altitudes by 2-3 kilometers, increasing the accessible surface area we can explore. They also will improve landing accuracy from a margin of 10 kilometers to just 3 kilometers. All these factors will increase the capabilities and robustness of robotic and human explorers on Mars.
NASA is now testing these devices on rocket sleds and later will conduct tests high in Earth’s stratosphere, simulating entry into Mars’ thin atmosphere. The first supersonic flight tests are set for 2013 and 2014.
