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.
One of the “weirdest and least understood” areas of Mars, the enormous Hellas Impact Basin contains strange flowing landforms that bespeak of some specialized and large-scale geologic process having taken place. The HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter recently captured the image above, showing what’s being called “lava lamp terrain” — stretched and contorted surface that looks like overworked modeling clay or pulled taffy… or, with a bit of imagination, the melted, mesmerizing contents of a party light from another era.
At 1,400 miles (2,300 km) across, Mars’ Hellas Basin is one of the largest impact craters in the entire Solar System. Its vast interior sinks to a depth of about 23,000 feet (7152 meters) below Mars’ average surface elevation (Martian “sea level”, if you will) and thus its floor is often shrouded by haze and dust, making visual imaging difficult.
The “lava lamp” terrain is just one of many different types of landforms that are found in the basin, although many of these banded features are found in the northwest area — which is also the deepest part of the basin. If there had been water in the region at some point in the planet’s history, it would have concentrated there.
Although the texture at first appears as if it could be volcanic in origin, it’s thought that flowing water or ice may actually be the source.
Researchers are currently working to determine how the Hellas Basin became so smoothly sculpted. Nicolas Thomas, Professor of Experimental Physics at the University of Bern, Switzerland, told Universe Today:
“There are a lot of very interesting images from this area and we are trying to get more data (including stereo) to understand better what’s going on and to try to establish what process is responsible for the numerous bizarre features we see. We are hoping to make some more progress in the next few months.”
Example of banded terrain. Compare the relatively fresh appearance of the bands with the older terrain seen to the left of this sub-image. (NASA/JPL/University of Arizona/N. Thomas et al.)
“Together with the observations of isolated areas and the lack of obvious caldera(s), it is difficult to envisage a volcanic origin for these features and we currently tend towards a mechanism involving ice,” Thomas stated in an abstract of a presentation given at the Europlanet Conference in 2010.
Read the full abstract here, and see this and more high-resolution images from Mars on the HiRISE website.
Curiosity Mars Science Laboratory (MSL) Spacecraft Cruising to Mars. Guided by the stars, Curiosity has reached the halfway point of its interplanetary cruise phase from the Earth to Mars in between launch on Nov. 26, 2011 and final approach in August 2012. MSL will use the stars to navigate. The spacecraft includes a disc-shaped solar powered cruise stage (on the left) attached to the aeroshell (right). Curiosity and the descent stage are tucked inside the aeroshell. Along the way to Mars, the cruise stage will perform six trajectory correction maneuvers (TCM’s) to adjust the spacecraft's path toward its final, precise landing site on Mars. Credit: NASA/JPL-Caltech
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As of today, NASA’s car sized Curiosity rover has reached the halfway point in her 352 million mile (567 million km) journey to Mars – No fooling on April 1, 2012.
It’s T Minus 126 days until Curiosity smashes into the Martian atmosphere to brave the hellish “6 Minutes of Terror” – and, if all goes well, touch down inside Gale Crater at the foothills of a Martian mountain taller than the tallest in the continental United States – namely Mount Rainier.
Curiosity will search for the ingredients of life in the form of organic molecules – the carbon based molecules which are the building blocks of life as we know it. The one-ton behemoth is packed to the gills with 10 state of the art science instruments including a 7 foot long robotic arm, scoop, drill and laser rock zapper.
The Curiosity Mars Science laboratory (MSL) rover was launched from sunny Florida on Nov. 26, 2011 atop a powerful Atlas V rocket for an 8.5 month interplanetary cruise from the Earth to Mars and is on course to land on the Red Planet early in the morning of Aug. 6, 2012 EDT and Universal Time (or Aug. 5 PDT).
Curiosity’s Position in Space on April 1, 2012 - Halfway to Mars
This roadmap shows Curiosity's flight path through the Solar System - From Earth to Mars during the 8.5 month interplanetary cruise. Credit: NASA/JPL-Caltech
On March 26, engineers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., successfully ignited the spacecrafts thrusters for the second of six planned trajectory correction maneuvers (TCM’s) to adjust the robot’s flight path during the long journey to achieve a pinpoint landing beside the Martian mountain.
“It is satisfying to get the second maneuver under our belts and know we are headed in the right direction,” said JPL’s Erisa Hines, systems lead for the maneuver. “The cruise system continues to perform very well.”
This maneuver was one-seventh as much as the flight’s first course adjustment, on Jan. 11. The cruise stage is equipped with eight thrusters grouped into two sets of four that fire as the entire spacecraft spins at two rotations per minute. The thruster firings change the velocity of the spacecraft in two ways – along the direction of the axis of rotation and also perpendicular to the axis. Altogether there were more than 60 pulsing maneuvers spaced about 10 seconds apart.
“The purpose is to put us on a trajectory to the point in the Mars atmosphere where we need to be for a safe and accurate landing,” said Mau Wong, maneuver analyst at JPL.
Atlas V rocket and Curiosity Mars rover poised at Space Launch Complex 41 at Cape Canaveral, Florida prior to Nov. 26, 2011 liftoff. Credit: Ken Kremer
Marking another crucial milestone, the flight team has also powered up and checked the status of all 10 MSL science instruments – and all are nominal.
“The types of testing varied by instrument, and the series as whole takes us past the important milestone of confirming that all the instruments survived launch,” said Betina Pavri of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., science payload test engineer for the mission. “These checkouts provide a valuable calibration and characterization opportunity for the instruments, including camera dark images and a measurement of zero pressure in the vacuum of space for the rover weather station’s pressure sensor.”
Ever since it was the first of MSL’s science instruments to be switched on three months ago, the Radiation Assessment Detector (RAD) has been collecting valuable measurements about the potentially lethal radiation environment in space and acting as a stunt double for determining the potential health effects on future human travelers to Mars.
RAD has been collecting data on the recent wave of extremely powerful solar flares erupting from the sun.
Curiosity has another 244 million kilometers to go over the next 4 months.
All hopes ride on Curiosity as America’s third and last generation of Mars rovers.
Devastating and nonsensical funding cuts to NASA’s Planetary Science budget have forced NASA to cancel participation in the 2018 ExoMars lander mission that had been joint planned with ESA, the European Space Agency. ESA now plans to forge ahead with Russian participation.
Stay tuned
Simulated view to Mars over the shoulder of Curiosity on 1 April 2012 - from current location halfway to the Red Planet. Credit: NASA/JPL-Caltech
Outflow channel in the Tharsis region on Mars. Credit: NASA/JPL/University of Arizona
Large features on Mars called outflow channels have been a point of contention among planetary scientists. “Most Mars scientists accept that outflow channels were carved by water, but alternate hypotheses persist, especially that lava carved the outflow channels,” said Alfred McEwen Principal Investigator of the HiRISE camera on the Mars Reconnaissance Orbiter. McEwen said that water is still the preferred mechanism and he doubts that all the channels could have been created by lava flows.
But in what could be seen as a type of compromise, he offered a new theory for the outflow channels, based on observations by HiRISE: the channels were originally carved by huge water flows on ancient Mars and later were partially filled in by lava.
“This sequence of events provides a better explanation,” McEwen said.
Large outflow channels can be 10 km or more in width and may be hundreds of kilometers long. From orbital images, they appear to be huge, dry river beds, carved by very large volumes of running water.
While these features are too large to have been caused by flooding from rainfall, other explanations have been offered. One model involves large amounts of water frozen as permafrost in the soil and when a major source of local heating occurred, such as volcanic activity, there was melting and catastrophic flooding.
However, other explanations don’t involve water at all, but suggest flowing lava created these channels.
Speaking at the 2012 Lunar and Planetary Science Conference last week, McEwen mentioned specifically one proponent of the lava hypothesis, David Leverington from Texas Tech University, who proposed last year that slippery, low-viscosity lavas created the channels. Leverington says the lava hypothesis offers a simpler explanation that fits well within a wider geological framework of Mars and compares well with similar channel-like features on the Moon and Venus.
“He makes some good points,” McEwen said, “and argues for a form of Occam’s Razor. But we have been searching extensively with HiRISE and finding things that satisfy Leverington’s challenges.”
McEwen said the abundant evidence of water carving the channels is too hard to dismiss. Several examples of outflow channels show deposits from water-based flooding that lava flow can’t explain; additionally, there is ample evidence of bedrock erosion by water on Mars.
McEwen also said crater dating areas of several outflow channels show that the channels themselves are older than the lava flow.
Part of Athabasca Valles, draped in lava. Credit: NASA/JPL/University of Arizona
“In the Athabasca Valles channels, MRO data showed that lava completely filled the channels and even overflow in places,” he said. “The lava can actually make channels look young.”
Uzboi Valles offers the best counterexample to Leverington’s hypothesis, McEwen said. “No lava fills in this highlands channel, and the channel preserves local layered alluvial deposits and shorelines. So that means we cannot explain all outflows channels from lava erosion.”
McEwen and his team suggest that large floods may have occurred in the Hesperian to early Amazonian, ending about 1 to 1.5 billion years ago, carving the channels. Then, later came the lava flows that formed Mars’ broad plains and sand dunes that we now see – which also filled in some of the outflow channels.
Bedrock Exposures in Uzboi Vallis. Credit: NASA/JPL/University of Arizona
But McEwen said the debate about these channels is good science. “Did water create these channels? That is a good question,” he said. “We shouldn’t just assume the answer is yes. But we propose water must have carved at least some of the channels, and that water outflow is the main mechanism. If you disagree with anything I’ve said, go to the HiRISE website’s “HiWish” page to suggest areas for further imaging of these features. I’ve been disappointed how few members of the science community have used this tool,” he said.
Clouds give a fuzzy view of ice-topped dunes on Mars. Credit: NASA/JPL/University of Arizona
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The science team from the HiRISE camera on the Mars Reconnaissance Orbiter wanted to take another look at a region of icy sand dunes on Mars to look for seasonal changes as spring is now arriving on the Red Planet’s northern hemisphere. But the view was obstructed by clouds, creating this unusual hazy view.
“This happens occasionally. We’ve found that weather forecasting on Mars is just as challenging — if not more — than on Earth,” said HiRISE team member Candy Hansen, who I nabbed in the hallway during the Lunar and Planetary Science Conference today, to ask about this unique image. “The clouds are likely made of water ice crystals, and the dunes have a coating of CO2 ice that is just starting to sublimate away as the Sun’s rays are getting stronger in this region.”
Hansen said these are dark barchan, or crescent-shaped dunes. During the winter, this region was completely covered with carbon dioxide ice, but now just the the tops of the dune have ice; also visible are what looks like white cracks, which is ice protected in shallow grooves on the ground. HiRISE will likely check back on this region later during the Martian summer to provide the science team with a seasonal sequence portfolio of images of the region, a benefit of having a mission in orbit for several years. MRO and HiRISE are workhorses, having been in orbit since March of 2006.
