ScienceCasts: Collision Course? A Comet Heads for Mars
A comet is heading for Mars, and there is a chance that it might hit the Red Planet in October 2014. An impact wouldn’t necessarily mean the end of NASA’s Mars program. But it would transform the program along with Mars itself.

via ScienceAtNASA

spaceplasma:

Meteorites on Mars

The sky falls on Mars, too, just as it does sometimes on Earth. In its long crosscountry drive over the pool table expanse of Meridiani Planum, Mars Exploration Rover Opportunity has encountered more than a dozen meteorites, all of them iron or stony-iron in composition.

Meteorites found on Mars are curiosities, but they can be something more than that, as a  paper in the Journal of Geophysical Research points out. A team of scientists led by James Ashley (Arizona State University) notes that because we have samples on Earth of the same kinds of meteorites found there, scientists can use the weathering seen on the Martian examples to probe bygone Martian climates.

The paper details three of Opportunity’s Mars meteorites, dubbed Block Island, Shelter Island, and Mackinac Island. Block Island was found by Opportunity on sol (Mars day) 1961 (July 31, 2009), Shelter Island on sol 2022 (October 1, 2009), and Mackinac Island on sol 2034 (October 14, 2009).Scientists are naming rocks of scientific interest after islands on earth.

 What’s most distinctive about these meteorites is that they show evidence for repeated episodes of weathering. For example, Block Island (an iron meteorite) shows two dramatically different faces: one smoothed, probably by sandblasting, and the other deeply pitted, probably by acidic corrosion. The corrosion likely occurred as thin films of water encountered iron sulfide minerals commonly found in iron meteorites.

Both Block Island and Shelter Island show evidence for multi-stage weathering. Close examination of their surfaces show that both have lost through weathering the fusion crusts that meteorites commonly develop as they speed through the atmosphere. Then exposure to water (or probably ice) created an oxydized (rusted) outer layer. This in turn has been largely scoured away by wind erosion.

There’s no way at present to determine how long those meteorites rested on the surface before Opportunity rolled by. But the weathering is unlikely to have happened recently, given Mars’ current arid, cold climate. Yet scientists know that over the last half million years at least, the planet’s spin axis has changed its tilt with respect to the Martian orbit. This has produced periods when snow and ice have come down from the polar regions and accumulated near the equator, probably including Meridiani Planum.

Credit: NASA/JPL

rhamphotheca:

Collision Course? A Comet Heads for Mars

by Dr. Tony Phillips

Over the years, the spacefaring nations of Earth have sent dozens of probes and rovers to explore Mars. Today there are three active satellites circling the red planet while two rovers, Opportunity and Curiosity, wheel across the red sands below.  Mars is dry, barren, and apparently lifeless.

Soon, those assets could find themselves exploring a very different kind of world.

“There is a small but non-negligible chance that Comet 2013 A1 will strike Mars next year in October of 2014,” says Don Yeomans of NASA’s Near-Earth Object Program at JPL.  “Current solutions put the odds of impact at 1 in 2000.”

The nucleus of the comet is probably 1 to 3 km in diameter, and it is coming in fast, around 56 km/s (125,000 mph). “It if does hit Mars, it would deliver as much energy as 35 million megatons of TNT,” estimates Yeomans…

(read more: NASA)

NASA’s Mars Spacecraft Go Solo Next Month

An unfavorable planetary alignment will force NASA’s fleet of robotic Mars explorers to be a lot more self-sufficient next month.

Mission controllers won’t send any commands to the agency’s various Mars spacecraft for much of April, because the sun will lie between Earth and the Red Planet during that time. Our star can disrupt and degrade interplanetary communications in such an alignment, which is known as a Mars solar conjunction, so spacecraft handlers won’t take any chances.

“Receiving a partial command could confuse the spacecraft, putting them in grave danger,” NASA officials explain in a video posted Tuesday (March 19) by the agency’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

Transmissions from Earth to the Mars rover Curiosity are slated to be suspended from April 4 to May 1, officials said. No commands will be sent to Curiosity’s older rover cousin Opportunity or NASA’s Mars-orbiting craft — Mars Odyssey and the Mars Reconnaissance Orbiter (MRO) — from April 9 to April 26.

Both rovers will continue to do stationary science work throughout the conjunction period, relying on commands sent up to them beforehand.

“We are doing extra science planning work this month to develop almost three weeks of activity sequences for Opportunity to execute throughout conjunction,” Opportunity mission manager Alfonso Herrera of JPL said in a statement.

MRO and Mars Odyssey will continue science observations as well, though on a more limited basis. The orbiters will also continue their role as rover communication links, receiving data from Opportunity and Curiosity.

Odyssey will send information — its own observations and the rovers’ data — Earthward throughout the conjunction period, though the mission team anticipates some dropouts, so Odyssey will send the data again later as needed.

MRO will take a different tack, storing everything from April 4 until after conjunction. The spacecraft’s operators estimate it will have about 52 gigabits of data onboard when it’s cleared to transmit to Earth again on May 1.

Mars solar conjunctions occur every 26 months, so all of the spacecraft have dealt with them except Curiosity, which landed on the Red Planet last August. Opportunity has been through five conjunctions since arriving on Mars in January 2004, but Odyssey is even more experienced.

“This is our sixth conjunction for Odyssey,” Chris Potts of JPL said in a statement. Potts is mission manager for Odyssey, which has been orbiting Mars since 2001. “We have plenty of useful experience dealing with them, though each conjunction is a little different.”

theatlantic:

In Focus: 9 Years on Mars

NASA’s Mars rover Opportunity just celebrated its ninth anniversary on Mars - a mission that was originally meant to last just 90 days. Although recently eclipsed in the news by its bigger brother Curiosity, Opportunity is still going strong and making valuable scientific discoveries. Launched into space in 2003, Opportunity bounced to a hole-in-one landing in a small crater on Mars’ Meridiani Planum on January 25, 2004. It has since spent 3,212 Martian days, or sols, on the surface, slowly moving from target to target, exploring craters, meteorites, unusual rock formations, and finding evidence of past water activity. Over the past 108 months, Opportunity has driven a total of 35.48 kilometers (22.05 miles) across Mars — not bad for a mission designed to last only three months. 

See more. [Images: NASA]

Finding Life in All the Unlikely, Unexpected Places

image: Just one of several weather stations set up at Chott El Jerid, a Tunisian saltpan, measuring temperature, humidity, ultraviolet radiation, wind direction and velocity.
credit: Felipe Goméz/Europlanet

From orbit and on the ground, Mars looks inhospitable. But it doesn’t look much different than the freezing Antarctic plains, sun-baked saltpans in Tunisia or Spain’s corrosively acidic Rio Tinto, according to a few explorers from the Centro de Astrobiología (CAB) in Madrid, who today presented some of their findings of life during a press conference at the European Planetary Science Congress.

The biggest difference, however, is that life still thrives in these extreme locales on Earth.

“The big questions are: what is life, how can we define it and what the requirements for supporting life?” asks project leader Dr. Felipe Goméz. “To understand the results we receive back from missions like Curiosity, we need to have detailed knowledge of similar environments on Earth. Metabolic diversity on Earth is huge. We have found a range of complex chemical processes that allow life to survive in unexpected places.”

Over the past four years, Goméz and his colleagues have checked Earth’s most inhospitable locales; the Chott el Jerid saltpan in Tunisia, the Atacama Desert in Chile, Rio Tinto in southern Spain and Deception Island in Antarctica.

While visiting Chott el Jerid, the team tracked huge changes in environmental conditions throughout the day but it was a small rise in surface temperature after dusk that caught their eye. “We found that this is caused by water condensing on the surface and hydrating salts which releases heat in an exothermic reaction,” he said in the press release. This is very interesting from the perspective of the REMS instrument on Curiosity — it gives us a way to follow when liquid water might be present on the surface.”

The team also built a three-dimensional picture of the subsurface in the saltpan by measuring the electrical properties of the soil. While drilling several meters into the subsurface at Chott el Jerid and in the Atacama Desert, researchers found bacteria at depth that was completely isolated from the surface. The researchers found not only bacteria, but also single-celled halophilic organisms that are able to oxidize metabolites under both aerobic and anaerobic conditions.

Along the surface of Chott El Jerid, which is made up of very pure sodium chloride with a trace of other salts, the team found small pieces of organic matter within the salt crystals. Once analyzed, they found populations of halophilic, salt-loving, dormant bacteria. In the laboratory, they were able to rehydrate the samples and bring the bacteria back to life, Goméz said.

Another unexpected find occurred while studying outcrops of the mineral jarosite at Rio Tinto in Spain. Jarosite, found on the surface of Mars by the Mars Exploration Rover Opportunity, forms only in the presence of water that contains high concentrations of metals, such as iron. The outcrops at Rio Tinto also are extremely corrosive. Yet, sandwiched between layers in the salt crusts, the team found photosynthetic bacteria. Unexpectedly, iron in the salt crust seems to protect bacteria from ultraviolet radiation, Goméz said. Samples of bacteria with iron present were exposed with high levels of ultraviolet radiation. They survived while bacteria samples without iron were destroyed.

“What the bacteria we found in Rio Tinto show is that the presence of ferric compounds can actually protect life. This could mean that life formed earlier on Earth than we thought. These effects are also relevant for the formation of life on the surface of Mars,” says Goméz. The team also found that salt provides stable conditions that can allow life to survive in very hard environments.

“Within salts, the temperature and humidity are protected from fluctuations and the doses of ultraviolet radiation are very low,” explained Goméz. “In the laboratory, we placed populations of different bacteria between layers of salt a few millimetres thick and exposed them to Martian conditions. Nearly 100% of deinoccocus radiodurans, a hardy type of bacteria survived being irradiated. But fascinatingly, about 40% of acidithiobacillus ferrooxidans – a very fragile variety of bacteria – also survived when protected by a salt crust.”

The findings have implications not only for studying possible life on Mars, but also for the development of life on early Earth.

Source: European Planetary Science Congress (EPSC) 2012 Press Release
Image Details: Photosynthetic bacteria at Rio Tinto. Credit: Felipe Goméz

pennyfournasa:

The true meaning of “off-roading.”

http://www.space.com/79-distances-driven-on-other-worlds.html

NASA’s Opportunity Rover Begins Year 10 on Mars

The older, smaller cousin of NASA’s huge Mars rover Curiosity is quietly celebrating a big milestone today (Jan. 24) — nine years on the surface of the Red Planet.

NASA’s Opportunity rover landed on Mars the night of Jan. 24, 2004 PST (just after midnight EST on Jan. 25), three weeks after its twin, Spirit, touched down. Spirit stopped operating in 2010, but Opportunity is still going strong, helping scientists better understand the Red Planet’s wetter, warmer past.

“No one could’ve imagined how good the exploration and scientific discovery would be for this vehicle, looking from the perspective of nine years ago,” said John Callas, Opportunity’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “It’s been a phenomenal accomplishment.”

The headline-stealing Curiosity rover, for its part, touched down on Aug. 5, 2012, marking the next step in Mars exploration. The car-size Curiosity weighs about 1 ton — five times more than either Spirit or Opportunity.

Long-lived rovers
Spirit and Opportunity were originally supposed to spend three months searching for evidence of past water activity on the Red Planet. The golf-cart-size robots found plenty of such signs at their separate landing sites, showing that Mars was not always the cold and arid planet we know today. [Most Amazing Discoveries by Spirit and Opportunity]

For example, in 2007 Spirit uncovered an ancient hydrothermal system in Gusev Crater, suggesting that two key ingredients for life as we know it — liquid water and an energy source — were both present in some parts of Mars long ago.

And Opportunity is currently inspecting clay deposits along the rim of Mars’ huge Endeavour Crater. Clays form in relatively neutral (as opposed to acidic or basic) water, so the area may once have been capable of supporting primitive microbial life, researchers say.

“This is our first glimpse ever at conditions on ancient Mars that clearly show us a chemistry that would’ve been suitable for life at the Opportunity site,” Opportunity principal investigator Steve Squyres, of Cornell University, said of the discovery at a conference last month.

The rovers rolled far beyond their 90-day warranties. Spirit finally stopped communicating with Earth in March 2010, after getting mired in soft sand and failing to maneuver into a position that would allow it to slant its solar panels toward the sun over the 2009-2010 Martian winter. NASA declared the rover dead in 2011.

But Opportunity keeps chugging along. It has put 22.03 miles (35.46 kilometers) on its odometer since landing on Mars — just 1 mile (1.6 km) off the all-time record for most ground covered on the surface of another world. The Soviet Union’s unmanned Lunokhod 2 rover holds that mark, traveling 23 miles (37 km) on the moon back in 1973.

The great engineering that allowed Spirit and Opportunity to keep roving for so long is a big part of the six-wheeled robots’ legacy, mission team members say.

“These are magnificently designed machines,” Callas told SPACE.com. “We really have greatly expanded the exploration envelope by having a vehicle that can not only last so long but stay in very good health over that time, such that we can continue exploring.”

Still in good health
While Opportunity is showing signs of its advanced age, such as an arthritic robotic arm, the rover remains in good shape overall.

“Its health right now is miraculously good,” Callas said.

Still, the rover team is treating every day as a gift at this point, knowing that Opportunity could conk out at pretty much any time. Indeed, the sun will rise one day without a message from Opportunity, and its handlers will have to face the rover’s death and the end of an amazing mission.

“It’s going to be hard; it’ll be the end of a great era,” Callas said. “But we’ll have to remember that we’ve had such a good run.”

NASA to Release ‘Changing Face of Mars’ Documentary

The recent acceleration of interest in space, fueled by commercial entities like SpaceX, Virgin Galactic, and emerging asteroid mining companies has opened the door to what appears to be a new era in science and technology.

Although NASA has grounded its space shuttles, and new deep space manned missions aren’t planned to take place until 2021, the agency’s Mars Curiosity rover program has kept it at the forefront of public interest. Now, NASA plans to further stoke that public interest by releasing a feature length documentary film.

Produced by NASA’s Jet Propulsion Laboratory (JPL), The Changing Face of Mars: Beginnings of the Space Age takes viewers on a journey that begins with myths about the Red Planet rooted in science fiction, to the first Mars probe in 1964 (the Mariner 4), to its latest research and missions to survey the planet’s surface for signs of water, and perhaps even microbial life. Helmed by Emmy award-winning director Blaine Baggett, who also happens to be the director of education and communication at JPL, the film uses archival footage and interviews with NASA engineers and scientists to offer a behind-the-scenes view of the agency’s history as well as its future plans for uncovering Mars’ secrets.

Just yesterday, NASA recognized the nearly decade-long presence of its Mars rover Opportunity on the planet, releasing a color panoramic image of the Matijevic Hill area photographed by the robotic vehicle.

“What’s most important is not how long [Opportunity] has lasted or even how far it has driven, but how much exploration and scientific discovery Opportunity has accomplished,” said John Callas, manager of NASA’s Mars Exploration Rover Project.

John Casani, the former chief engineer at JPL, will host the 90-minute film’s premiere tonight at the California Institute of Technology Pasadena. The free event will also allow visitors to view a full-scale model of the Curiosity rover. There’s no word on when the film will be distributed to the general public, but in the meantime you can watch the trailer above.

pennyfournasa:

While NASA’s Curiosity Rover is absorbing all the spotlight, it’s easy to forget it’s not the only rover roaming the Martian surface.  NASA’s Opportunity Rover is embarking on it’s 10th year of exploration, despite only being tasked to operate for 3 months.

http://hosted.ap.org/dynamic/stories/U/US_SCI_MARS_ROVER

Want To Continue Mars Exploration? Tell Congress To Double NASA’s Budget:
http://www.penny4nasa.org/take-action/

Watery Science ‘Jackpot’ Discovered by Curiosity

Image: Curiosity found widespread evidence for flowing water in the highly diverse, rocky scenery shown in this photo mosaic from the edge of Yellowknife Bay on Sol 157 (Jan 14, 2013). The rover will soon conduct 1st Martian rock drilling operation at flat, light toned rocks at the outcrop called “John Klein”, at center. ‘John Klein’ drill site and ‘Sheep Bed’ outcrop ledges to right of rover arm are filled with numerous mineral veins and spherical concretions which strongly suggest precipitation of minerals from liquid water. ‘Snake River’ rock formation is the linear chain of rocks protruding up from the Martian sand near rover wheel. Credit: NASA/JPL-Caltech/Ken Kremer/Marco Di Lorenzo

The Curiosity rover hit the science “jackpot” and has discovered widespread further evidence of multiple episodes of liquid water flowing over ancient Mars billions of years ago when the planet was warmer and wetter, scientists announced. The watery evidence comes in the form of water bearing mineral veins, cross-bedded layering, nodules and spherical sedimentary concretions.

Any day now the robot will be instructed to drill directly into veined rocks where water once flowed, the team announced at a media briefing this week.

Delighted researchers said Curiosity surprisingly found lots of evidence for light-toned chains of linear mineral veins inside fractured rocks littering the highly diverse Martian terrain – using her array of ten state-of-the-art science instruments. Veins form when liquid water circulates through fractures and deposit minerals, gradually filling the insides of the fractured rocks over time.

Sometime in the next two weeks or so, NASA’s car sized rover will carry out history’s first ever drilling inside a Martian rock that was “percolated” by liquid water – an essential prerequisite for life as we know. A powdered sample will then be delivered to the robots duo of analytical chemistry labs (CheMin & SAM) to determine its elemental composition and ascertain whether organic molecules are present.

The drill target area is named “John Klein” outcrop, in tribute to a team member who was the deputy project manager for Curiosity at JPL for several years and who passed away in 2011.

“We identified a potential drill target and are preparing to do drill activities in the next two weeks. We are ready to go,” said Richard Cook, the project manager of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“Drilling [into a rock] is the most significant engineering activity since landing. It is the most difficult aspect of the surface mission, interacting with an unknown surface terrain, and has never been done on Mars. We will go slowly. It will take some time to deliver samples to CheMin and SAM and will be a great set of scientific measurements.”

Image caption: Mineral veins of calcium sulfate discovered by Curiosity at ‘Sheepbed’ Outcrop. These veins form when water circulates through fractures, depositing minerals along the sides of the fracture, to form a vein. These vein fills are characteristic of the stratigraphically lowest unit in the “Yellowknife Bay” area where Curiosity is currently exploring and were imaged on Sol 126 (Dec. 13, 2012) by the telephoto Mastcam camera. Image has been white-balanced. Credit: NASA/JPL-Caltech/MSSS

“The scientists have been let into the candy store,” said Cook referring to the unexpected wealth of science targets surrounding the rover at this moment.

Curiosity is just a few meters away from ‘John Klein’ and will drive to the site shortly from her location inside ‘Yellowknife Bay’ beside the ‘Snake River’ rock formation. To see where Curiosity is in context with ‘John Klein’ and “Snake River’, see our annotated context mosaic (by Ken Kremer & Marco Di Lorenzo) as the rover collects data at a rock ledge.

The white colored veins were discovered over the past few weeks- using the high resolution mast- mounted imaging cameras and ChemCam laser firing spectrometer -at exactly the vicinity where Curiosity is currently investigating ; around a shallow basin called Yellowknife Bay and roughly a half mile away from the landing site inside Gale Crater.

“This lowest unit that we are at in Yellowknife Bay, the very farthest thing we drove to, turns out to be kind of the ‘jackpot’ unit here,” said John Grotzinger, the mission’s chief scientist of the California Institute of Technology. “It is literally shot through with these fractures and vein fills.”

Image caption: ‘John Klein’ Site Selected for Curiosity’s Drill Debut. This view shows the patch of veined, flat-lying rock selected as the first drilling site. The rover’s right Mast Camera equipped with a telephoto lens, was about 16 feet (5 meters) away from the site when it recorded this mosaic on sol 153 (Jan. 10, 2013). The area is shot full of fractures and veins, with the intervening rock also containing concretions, which are small spherical concentrations of minerals. Enlargement A shows a high concentration of ridge-like veins protruding above the surface. Some of the veins have two walls and an eroded interior. Enlargement B shows that in some portions of this feature, there is a horizontal discontinuity a few centimeters or inches beneath the surface. The discontinuity may be a bed, a fracture, or potentially a horizontal vein. Enlargement C shows a hole developed in the sand that overlies a fracture, implying infiltration of sand down into the fracture system. Image has been white-balanced. Credit: NASA/JPL-Caltech/MSSS

Shortly after landing the team took a calculated gamble and decided to take a several months long detour away from the main destination of the towering, sedimentary mountain named Mount Sharp, and instead drive to an area dubbed ‘Glenelg’ and home to ‘Yellowknife Bay’, because it sits at the junction of a trio of different geologic terrains. Glenelg exhibits high thermal inertia and helps put the entire region in better scientific context. The gamble has clearly payed off.

“We chose to go there because we saw something anomalous, but wouldn’t have predicted any of this from orbit,” said Grotzinger.

The Chemistry and Camera (ChemCam) instrument found elevated levels of calcium, sulfur and hydrogen. Hydrogen is indicative of water.

The mineral veins are probably comprised of calcium sulfate – which exists in several hydrated (water bearing) forms.

“The ChemCam spectra point to a composition very high in calcium. These veins are likely composed of hydrated calcium sulfate, such as bassinite or gypsum, depending on the hydration state,” said ChemCam team member Nicolas Mangold of the Laboratoire de Planétologie et Géodynamique de Nantes in France. “On Earth, forming veins like these requires water circulating in fractures and occur at low to moderate temperatures.”

The newly found veins appear quite similar to analogous veins discovered in late 2011 by NASA’s Opportunity rover – Curiosity’s older sister – inside Endeavour crater and nearly on the opposite side of Mars. See our Opportunity vein mosaic featured at APOD on Dec. 11, 2011 to learn more about veined rocks.

“What these vein fills tell us is water moved and percolated through these rocks, through these fracture networks and then minerals precipitated to form the white material which ChemCam has concluded is very likely a calcium sulfate, probably hydrated in origin,” Grotzinger explained.

“So this is the first time in this mission that we have seen something that is not just an aqueous environment, but one that also results in precipitation of minerals, which is very attractive to us.”

Yellowknife Bay and the ‘John Klein’ drilling area outcrop are chock full of mineral veins and sedimentary concretions.

“When you put all this together it says that basically these rocks were saturated with water. There may be several phases to this history of water, but that’s still to be worked out.”

“This has been really exciting and we can’t wait to start drilling,” Grotzinger emphasized.

Curiosity can drill about 2 inches (5 cm) into rocks. Ultimately a powdered sample about half an aspirin tablet in size will be delivered to SAM and CheMin after a few weeks. All rover systems and instruments are healthy, said Cook.

Grotzinger said that Curiosity will be instructed to drive over the veins to try and break them up and expose fresh surfaces for analysis. Then she will drill directly into a vein and hopefully catch some of the surrounding material as well.

“This will reveal the mineralogy of the vein filling material and how many hydrated mineral phases are present. The main goal is this will give us an assessment of the habitability of this environment.”

As the rover has driven down the shallow depression to deeper stratigraphic layers, the units are older in time. After the first drill sample is fully analyzed, Grotzinger told me that the team will reevaluate whether to drill into a second rock.

The team doesn’t yet know whether the flowing water from which the veins precipitated was a more neutral pH or more acidic. “It’s too early to tell. We need to drill into the rock to tell and determine the mineralogy,” Grotzinger told me. Neutral water is more hospitable to life.

How long the episodes of water flowed is not yet known and it’s a complex history. But the water was at least hip to ankle deep at times and able to transport and round the gravel.

Image caption: Curiosity’s Traverse into Different Terrain. This image maps the traverse of NASA’s Mars rover Curiosity from “Bradbury Landing” to “Yellowknife Bay,” with an inset documenting a change in the ground’s thermal properties with arrival at a different type of terrain. Credit: NASA/JPL-Caltech/Univ. of Arizona/CAB(CSIC-INTA)/FMI

Drilling goes to the heart of the mission and will mark a historic feat in planetary exploration – as the first time that an indigenous sample has been cored from the interior of a rock on another planet and subsequently analyzed by chemical spectrometers to determine its elemental composition and determine if organic molecules are present .

The high powered hammering drill is located on the tool turret at the end of the car-sized robots 7 foot (2.1 meter) long mechanical arm . It is the last of Curiosity’s ten instruments that remains to be checked out and put into action.

Curiosity landed on the Red Planet five months ago inside Gale Crater to investigate whether Mars ever offered an environment favorable for microbial life, past or present and is now nearly a quarter of the way through her two year prime mission.

Curiosity might reach the base of Mount Sharp by the end of 2013, which is about 6 miles (10 km) away as the Martian crow flies.

Image Caption: Calcium-Rich Veins in Martian Rocks. This graphic shows close-ups of light-toned veins in rocks in the “Yellowknife Bay” area of Mars together with analyses of their composition. The top part of the image shows a close-up of the rock named “Crest,” taken by the remote micro-imager (RMI) on Curiosity’s Chemistry and Camera (ChemCam) instrument above the analysis of the elements detected by using ChemCam’s laser to zap the target. The spectral profile of Crest’s light-colored vein is shown in red, while that of a basaltic calibration target of known composition is shown in black. The bottom part of the image shows ChemCam’s close-up of the rock named “Rapitan” with the analysis of its elemental composition. The spectral profile of Rapitan’s light-colored vein is shown in blue, while that of a basaltic calibration target of known composition is shown in black. These results suggest the veins are unlike typical basaltic material. They are depleted in silica and composed of a calcium-bearing mineral.
Credit: NASA/JPL-Caltech/LANL/CNES/IRAP/LPGNantes/CNRS

distant-traveller:

Clays on Mars: More plentiful than expected

A new study co-authored by the Georgia Institute of Technology indicates that clay minerals, rocks that usually form when water is present for long periods of time, cover a larger portion of Mars than previously thought. In fact, Assistant Professor James Wray and the research team say clays were in some of the rocks studied by Opportunity when it landed at Eagle crater in 2004. The rover only detected acidic sulfates and has since driven about 22 miles to Endeavour Crater, an area of the planet Wray pinpointed for clays in 2009.

The project, which was led by Eldar Noe Dobrea of the Planetary Science Institute, identified the clay minerals using a spectroscopic analysis from the Mars Reconnaissance Orbiter. The research shows that clays also exist in the Meridiani plains that Opportunity rolled over as it trekked toward its current position.

The clay signatures near Eagle crater are very weak, especially compared to those along the rim and inside Endeavour crater. It is believed that clays could have been more plentiful in the past, but Mars’ volcanic, acidic history has probably eliminated some of them.

“It was also surprising to find clays in geologically younger terrain than the sulfates,” said Dobrea. Current theories of Martian geological history suggest that clays, a product of aqueous alteration, actually formed early on when the planet’s waters were more alkaline. As the water acidified due to volcanism, the dominant alteration mineralogy became sulfates. “This forces us to rethink our current hypotheses of the history of water on Mars,” he added.

Even though Opportunity has reached an area believed to contain rich clay deposits, the odds are still stacked against it. Opportunity was supposed to survive for only three months. It’s still going strong nine years later, but the rover’s two mineralogical instruments don’t work anymore. Instead, Opportunity must take pictures of rocks with its panoramic camera and analyze targets with a spectrometer to try and determine the composition of rock layers.

Image credit: NASA/JPL

Opportunity Rover Finds Mars Minerals that Formed in Life-Friendly Water

image 1: Opportunity image of light, flat rocks containing clay and mysterious darker rocks jutting through them. NASA/JPL-Caltech/ Cornell Univ./Arizona State Univ
image 2: Image: The mysterious ‘newberries’ that Opportunity is now exploring. NASA/JPL-Caltech/Cornell Univ./ USGS/Modesto Junior College

While attention has been focused on the Mars rover Curiosity, NASA’s other active Mars rover, Opportunity, has quietly been going about its business and may have stumbled across an intriguing new geologic puzzle. Opportunity has begun examining ancient clays on Mars that would have formed in the presence of water with neutral acidity, a condition favorable for life as we know it.

“This is our first glimpse ever at an ancient Mars where conditions would be suitable for life,” said astronomer Steve Squyres of Cornell University, the lead scientist for Opportunity’s mission, here at the American Geophysical Union conference on Dec 4.

Previous minerals that Opportunity and its defunct twin Spirit had found thus far on Mars would have required extremely harsh conditions to form, something akin to battery acid, and not very conducive to life. The clays that the rover is now exploring would have been created billions of years earlier in water with a neutral pH. “These clays point to water you could drink,” said Squyres.

Since it landed on Mars in 2004, Opportunity has roved more than 22 miles. After nine years on Mars, the rover is getting a bit old, with a squeaky right front wheel and a creaky arm joint, though is overall in good condition. Last year, the probe arrived at Endeavor crater, where it discovered the most unambiguous evidence for water on ancient Mars ever found.

Scientists directed Opportunity to Endeavor crater to study the clays, which had been spotted earlier from orbit. Roving around one of the half-buried rims of the crater, Opportunity found a small hill that Squyres described as the “sweet spot” where clays are known to be present. The rover took photos showing two types of rocks.

The dominant material is light-toned, flat-lying, and easily eroded by Martian wind. This is the rock that contains the clays and shows a chemistry typical of Martian material. But Opportunity also found a fin sticking up through the dominant rocks made of another material that is dark, grey, and more resistant to erosion.

“What we have stumbled upon is what is turning out to be one of the most delightful geologic puzzles we have ever found on Mars,” said Squyres.

When they drove up to the fin, the science team found it covered in a dense concentration of spherical bubbles quite similar looking to the iron-containing Martian “blueberries” that Opportunity has seen before. But when they looked at the chemical composition of these spheres, scientists found they contained no iron.

“It’s something totally different, and I’ve started calling them ‘newberries’,” said Squyres.

The team doesn’t yet know what these newberries are made of and will spend the next few months investigating them. They could be mineral concretions, impact ejecta spherules, or volcanic hailstones. Squyres said that researchers will also examine the clays to determine what conditions on early Mars would have been like. He said many questions remained and Opportunity had a lot of work ahead of it.

“It’s like we’ve been exploring Mars for nine years, and now Mars has given us a final exam,” said Squyres.

i don’t know if anyone realizes how big this week is for umm…history, life, everything? pay attention…

via giantfreakinrobot…

Tuesday, the deep recesses of space and the ocean take center stage. Gorgeous images and fascinating information gleaned from the Van Allen probes will be shared. There will be a briefing on the Mars rover Opportunity’s investigation of “Matijevic Hill,” on the rim of the Endeavour Crater, covering the possible presence of clay materials. James Cameron name-drop. His DEEPSEA CHALLENGE expedition gets its due, as the designers and crew, along with Cameron himself, will go in-depth about all details of the vehicle, and Cameron’s lone journey to Earth’s deepest point. Enjoy the light-hearted comedy associated with discovering clandestine nuclear-bomb-testing areas, and how climate change has affected our nation’s rampant wildfires.

Wednesday’s subjects appear drab in comparison, but are no less important. The GRAIL moon gravity mapping mission of spacecraft Ebb and Flow will give us the most high-def images of any celestial body ever. An updated, cloud-free Earth at Night photo will be revealed, as well as other photos from moonless nights, when only “airglow” and starlight are visible light sources. The Arctic’s decline in snow and rise in melting ice, without fluctuating temperatures, will be discussed, as will earthquakes occurring outside of faultlines and the amount of carbon caught up in the atmosphere above much of the western U.S.

Thursday only has two panels, and both are introspective. Should the Age of Man actually be an Age of Man? The definition and process of defining an epoch will be reviewed, as will considerations for the possible beginnings to our current era. Finally, scientists will look at the effects from the guilty verdicts of the Italian scientists involved in the L’Aquila Earthquake case, and they will discuss a change in thought over the responsibilities of those involved with natural hazards studies.

i certainly do not agree with the light-heartedness of this write-up, considering the crazy reality we exist in that allows us to even speak about the scientific ventures currently taking place, but i believe you get the point. if you’ve been following even half of the above scientific research & projects, i’m sure you’re as amped as i am right now.

big things coming people. big things.

Can Humans Live on Mars?

Image 1: Curiosity is taking the first ever radiation measurements from the surface of another planet in order to determine if future human explorers can live on Mars – as she traverses the terrain of the Red Planet. Curiosity is looking back to her rover tracks and the foothills of Mount Sharp and the eroded rim of Gale Crater in the distant horizon on Sol 24 (Aug. 30, 2012). This panorama is featured on PBS NOVA ‘Ultimate Mars Challenge’ documentary which premiered on PBS TV on Nov. 14. RAD is located on the rover deck in this colorized mosaic stitched together from Navcam images by the image processing team of Ken Kremer & Marco Di Lorenzo. Credit: NASA / JPL-Caltech / Ken Kremer / Marco Di Lorenzo

Image 2: Longer-Term Radiation Variations at Gale Crater. This graphic shows the variation of radiation dose measured by the Radiation Assessment Detector on NASA’s Curiosity rover over about 50 sols, or Martian days, on Mars. (On Earth, Sol 10 was Sept. 15 and Sol 60 was Oct. 6, 2012.) The dose rate of charged particles was measured using silicon detectors and is shown in black. The total dose rate (from both charged particles and neutral particles) was measured using a plastic scintillator and is shown in red. Credit: NASA/JPL-Caltech/ SwRI

Image 3: Curiosity Self Portrait with Mount Sharp at Rocknest ripple in Gale Crater. Curiosity used the Mars Hand Lens Imager (MAHLI) camera on the robotic arm to image herself and her target destination Mount Sharp in the background. Mountains in the background to the left are the northern wall of Gale Crater. This color panoramic mosaic was assembled from raw images snapped on Sol 85 (Nov. 1, 2012). Credit: NASA/JPL-Caltech/MSSS/Ken Kremer/Marco Di Lorenzo

Image 4: Daily Cycles of Radiation and Pressure at Gale Crater. This graphic shows the daily variations in Martian radiation and atmospheric pressure as measured by NASA’s Curiosity rover. As pressure increases, the total radiation dose decreases. When the atmosphere is thicker, it provides a better barrier with more effective shielding for radiation from outside of Mars. At each of the pressure maximums, the radiation level drops between 3 to 5 percent. The radiation level goes up at the end of the graph due to a longer-term trend that scientists are still studying. Credit: NASA/JPL-Caltech/SwRI

Metallic robots constructed by ingenious humans can survive on Mars. But what about future human astronauts?

NASA’s plucky Mars Exploration Rover Opportunity has thrived for nearly a decade traversing the plains of Meridiani Planum despite the continuous bombardment of sterilizing cosmic and solar radiation from charged particles thanks to her radiation hardened innards.

How about humans? What fate awaits them on a bold and likely year’s long expedition to the endlessly extreme and drastically harsh environment on the surface of the radiation drenched Red Planet - if one ever gets off the ground here on Earth? How much shielding would people need?

Answering these questions is one of the key quests ahead for NASA’s SUV sized Curiosity Mars rover – now 100 Sols, or Martian days, into her 2 year long primary mission phase.

Preliminary data looks promising.

Curiosity survived the 8 month interplanetary journey and the unprecedented sky crane rocket powered descent maneuver to touch down safely inside Gale Crater beside the towering layered foothills of 3 mi. (5.5 km) high Mount Sharp on Aug. 6, 2012.

Now she is tasked with assessing whether Mars and Gale Crater ever offered a habitable environment for microbial life forms – past or present. Characterizing the naturally occurring radiation levels stemming from galactic cosmic rays and the sun will address the habitability question for both microbes and astronauts. Radiation can destroy near-surface organic molecules.

Researchers are using Curiosity’s state-of-the-art Radiation Assessment Detector (RAD) instrument to monitor high-energy radiation on a daily basis and help determine the potential for real life health risks posed to future human explorers on the Martian surface.

“The atmosphere provides a level of shielding, and so charged-particle radiation is less when the atmosphere is thicker,” said RAD Principal Investigator Don Hassler of the Southwest Research Institute in Boulder, Colo. See the data graphs herein.

“Absolutely, the astronauts can live in this environment. It’s not so different from what astronauts might experience on the International Space Station. The real question is if you add up the total contribution to the astronaut’s total dose on a Mars mission can you stay within your career limits as you accumulate those numbers. Over time we will get those numbers,” Hassler explained.

The initial RAD data from the first two months on the surface was revealed at a media briefing for reporters on Thursday, Nov. 15 and shows that radiation is somewhat lower on Mars surface compared to the space environment due to shielding from the thin Martian atmosphere.

RAD hasn’t detected any large solar flares yet from the surface. “That will be very important,” said Hassler.

“If there was a massive solar flare that could have an acute effect which could cause vomiting and potentially jeopardize the mission of a spacesuited astronaut.”

“Overall, Mars’ atmosphere reduces the radiation dose compared to what we saw during the cruise to Mars by a factor of about two.”

RAD was operating and already taking radiation measurements during the spacecraft’s interplanetary cruise to compare with the new data points now being collected on the floor of Gale Crater.

Mars atmospheric pressure is a bit less than 1% of Earth’s. It varies somewhat in relation to atmospheric cycles dependent on temperature and the freeze-thaw cycle of the polar ice caps and the resulting daily thermal tides.

“We see a daily variation in the radiation dose measured on the surface which is anti-correlated with the pressure of the atmosphere. Mars atmosphere is acting as a shield for the radiation. As the atmosphere gets thicker that provides more of a shield. Therefore we see a dip in the radiation dose by about 3 to 5%, every day,” said Hassler.

There are also seasonal changes in radiation levels as Mars moves through space.

The RAD team is still refining the radiation data points.

“There’s calibrations and characterizations that we’re finalizing to get those numbers precise. We’re working on that. And we’re hoping to release that at the AGU [American Geophysical Union] meeting in December.”

Radiation is a life limiting factor to habitability. RAD is the first science instrument to directly measure radiation from the surface of a planet other than Earth.

“Curiosity is finding that the radiation environment on Mars is sensitive to Mars weather and climate,” Hassler concluded.

Unlike Earth, Mars lost its magnetic field some 3.5 billion years ago – and therefore most of it’s shielding capability from harsh levels of energetic particle radiation from space.

Much more data will need to be collected by RAD before any final conclusions on living on Mars, and for how long and in which type habitats, can be drawn.