A view of the interior of a meteorite from Mars shows a vein through which water has flowed. Credit: University of Leicester
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Scientists say a close-up look inside rare meteorite fragments from Mars shows evidence that impacts created flowing water near the surface of the Red Planet. At look at five different meteorite samples, including what is thought the be one of the very first Martian meteorite ever found on Earth, shows veins resulting from the impact and serpentine mineralization, which is associated with the production of methane.
PhD student Hitesh Changela and Dr. John Bridges from the University of Leicester used electron microscopes to study the structure and composition of five nakhlite meteorites, including one that was found in 1911 in El-Nakhla in Egypt (the meteorites were named after the location in which they were found). The meteorites had been housed in Natural History Museum, London, and the scientists sliced minute slivers of rock from the samples, about 0.1 microns thick.
By comparing the five meteorites, they showed the presence of veins created during an impact on Mars. Changela and Bridges suggest that this impact was associated with a 1-10 km diameter impact crater, and buried ice melted during this impact, creating flowing water which then deposited clay, serpentine minerals, carbonate and a gel deposit in the veins.
The scientists say their findings tie in with the recent water-related geological discoveries of clay and carbonate on the surface of Mars made by NASA and ESA orbiting spacecraft and the Mars Exploration rovers.
Nanometre scale atomic lattice spacings (measured by high resolution TEM) in serpentine. Credit: University of Leicester
“We are now starting to build a realistic model for how water deposited minerals formed on Mars,” said Bridges, “showing that impact heating was an important process. The constraints we are establishing about temperature, pH and duration of the hydrothermal action help us to better understand the evolution of the Mars surface. This directly ties in with the current activities of landing site selection for Mars rovers and Mars Sample Return. With models like this we will better understand the areas where we think that water was once present on Mars.”
Since serpentine mineralization is associated with the production of methane, the scientists say further research on the meteorites could help show how the methane was produced. A mission heading to Mars in 2016, the Trace Gas Orbiter, will help search for and understand the origin of any methane — a potential biomarker — in Mars’ atmosphere.
Findings from the research have been published in Meteoritics and Planetary Science (Dec. 2010 issue, vol 45).
This map indicates geological units in the region of Mars around a smaller area where Opportunity has driven from early 2004 through late 2010. The blue-coded unit encompassing most of the southern half of the mapped region is ancient cratered terrain. In the northern region, it is overlain by younger sediments of the Meridiani Plains, punctuated by the even younger Bopulu impact. At Endeavour Crater, in the upper right near the gold line of Opportunity's traverse, ancient cratered terrain is exposed around the crater rim. Locations where orbital observations have detected clay minerals are indicated at the western edge of Endeavour and at two locations in the southern portion of the map. The mineral mapping was done by Sandra Wiseman and Ray Arvidson of Washington Universty in St. Louis based on observations by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) on NASA's Mars Reconnaissance Orbiter.
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NASA is using its powerful science surveyor orbiting more than 241 kilometers above Mars to target the surface explorations of the long lived Opportunity rover to compelling science targets on the ground. Opportunity is currently on a long term trek to the giant crater named Endeavour, some 22 kilometers in diameter, which shows significant signatures of clays and water bearing sulfate minerals which formed in the presence of flowing liquid water billions of years ago.
An armada of orbiters and rovers from Earth are carrying out a coordinated attack plan to unlock the mysteries of the red planet, foremost being to determine whether life ever arose on Mars.
On Dec. 15 (Sol 2450), Opportunity arrived at Santa Maria crater which is just 6 km distant from the western rim of Endeavour. Over the past 2 years, the rover has traversed more than two thirds of the 19 km distance from Victoria crater -her last big target – to Endeavour.
High resolution spectral and imaging mappers aboard NASA’s Mars Reconnaissance Orbiter (MRO) are enabling researchers on the rover team to prioritize targets and strategically guide Opportunity to the most fruitful locations for scientific investigations.
The on board CRISM mapping spectrometer has detected clay minerals, or phyllosilicates, at multiple locations around Endeavour crater including the western rim closest to Opportunity. CRISM is the acronym for Compact Reconnaissance Imaging Spectrometer for Mars. Images from MRO’s HiRISE camera are utilized to scout out the safest and most efficient route. See maps above and below.
“This is the first time mineral detections from orbit are being used in tactical decisions about where to drive on Mars,” said Ray Arvidson of Washington University in St. Louis. Arvidson is the deputy principal investigator for the Spirit and Opportunity rovers and a co-investigator for CRISM.
Clay minerals are a very exciting scientific find because they can form in more neutral and much less acidic aqueous environments which are more conducive to the possibility for the formation of life. They have never before been studied up close by science instruments on a landed mission.
Opportunity may soon get a quick taste of water bearing sulfate minerals at Santa Maria because spectral data from CRISM suggest the presence of sulfate deposits at the southeast rim of the crater. Opportunity has previously investigated these sulfate minerals at other locations along her circuitous traverse route – but which she discovered without the help of orbital assets.
“We’ve just pulled up to the rim of Santa Maria, and the workload is very high,” Steve Squyres informed me. Squyres, of Cornell University, is the Principal Scientific Investigator for NASA’s Spirit and Opportunity Mars rovers.
Opportunity drove to within about 5 meters of the crater rim on Dec. 16 (Sol 2451). JPL Mars rover driver Scott Maxwell tweeted this message ; “Today’s NAVCAM mosaic of Santa Maria Crater. Woo-hoo! Glorious and beautiful!” and this twitpic
Orbital Observations at Santa Maria Crater.
Opportunity just arrived at the western side of Santa Maria Crater, some 90 meters wide, on 15 December 2010. Researchers are using data collected by a powerful mineral mapping spectrometer (CRISM) aboard NASA’s Mars Reconnaissance Orbiter (MRO) to direct the route which Opportunity is traversing on Mars during the long term journey to Endeavour crater. Spectral observations recorded by CRISM indicates the presence of water-bearing sulfate minerals at the location shown by the red dot on the southeast rim crater whereas the crater floor at the blue dot does not. This image was taken by the the High Resolution Imaging Science Experiment (HiRISE) camera also on MRO. Credit: NASA/JPL-Caltech/Univ. of Arizona
The rover will conduct an extensive science campaign at Santa Maria by driving to different spots over the next several weeks and gathering data to compare observations on the ground to those from CRISM in orbit.
Opportunity Navcam camera view of Santa Maria Crater just 5 m from the rim on Sol 2451, Dec. 16, 2010. Click to enlarge
Santa Maria crater appears to be relatively fresh and steep walled and was likely created by a meteor strike only a few million years ago. Endeavour is an ancient crater with a discontinuous rim that is heavily eroded at many points. By exploring craters, scientists can look back in time and decipher earlier geologic periods in Mars history.
Scientists believe that the clay minerals stem from an earlier time period in Martian history and that the sulfate deposits formed later. Mars has experiences many episodes of wet environments at diverse locations in the past and climate-change cycles persist into the present era.
After the upcoming Solar Conjunction in February 2011, Opportunity will depart eastwards for the last leg of the long march to Endeavour. She heads for a rim fragment dubbed Cape York which spectral data show is surrounded by exposures of water bearing minerals. Cape York is not yet visible in the long distance images because it lies to low. See maps below.
Thereafter, Opportunity alters direction and turns south towards her next goal –
Cape Tribulation – which is even more enticing to researchers because CRISM has detected exposures of the clay minerals formed in the milder environments more favorable to life. Cape Tribulation has been clearly visible in rover images already taken months ago in early 2010.
Opportunity could reach Endeavour sometime in 2011 if she can continue to survive the harsh environment of Mars and drive at her current accelerated pace. Opportunity arrived at Mars in January 2004 for a planned 90 day mission. The rover has far surpassed all expectations and will soon celebrate 7 earth years of continuous operations on the red planet. Virtually all the data from Spirit and Opportunity are relayed back to Earth via NASA’s Mars Odyssey orbiter.
Opportunity used its panoramic camera in a super-resolution technique to record this view of the horizon on Sol 2298 (July 11, 2010) which shows the western rim of Endeavour Crater, including the highest ridge informally named “Cape Tribulation”. CRISM data revealed exposures of clay minerals at Cape Tribulation.
Opportunity’s Path on Mars Through Sol 2436
The red line shows where Opportunity has driven from the place where it landed in January 2004 — inside Eagle Crater, at the upper left end of the track — to where it reached on the 2,436th Martian day, or sol, of its work on Mars (Nov. 30, 2010). The map covers an area about 15 kilometers (9 miles) wide. North is at the top. Subsequent drives brought Opportunity to Santa Maria Crater, which is about 90 meters (295 feet) in diameter. After investigating Santa Maria the rover heads for Endeavour Crater. The western edge of 22-kilometer-wide (14-mile-wide) Endeavour is in the lower right corner of this map. Some sections of the discontinuous raised rim and nearby features are indicated with informal names on the map: rim segments “Cape York” and “Solander Point”; a low area between them called “Botany Bay”; “Antares” crater, which formed on sedimentary rocks where the rim was eroded down; and rim fragment “Cape Tribulation,” where orbital observations have detected clay minerals. The base map is a mosaic of images from the Context Camera on NASA’s Mars Reconnaissance Orbiter.
The Cooper Basin hides an impact crater that was recently discovered by geothermal energy researchers. The crater may be the second largest discovered in Australia. Image Credit: Southern Australia Dept. of Transport, Energy and Infrastructure
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Geothermal energy researchers from the University of Queensland in Australia have identified what may be the second largest meteorite impact crater in Australia. Dr. Tonguç Uysal of the University of Queensland and Dr. Andrew Glikson of Australian National University identified rock structures that appear to have formed because of the shock of a meteorite impact. Their discovery was made while doing geothermal energy research in the Cooper Basin, which lies on the border between Queensland and South Australia.
The meteorite that caused the impact was likely 8 to 12 km in diameter (5 to 7.5 miles), Dr. Glikson said in an interview. It is also possible that a cluster of smaller meteorites impacted the region, so further testing is needed to pin down the exact nature of the impactor. The impact likely occurred over 300 million years ago, and the shock of the impact altered rock in a zone 80 km (50 miles) in diameter.
Dr. Glikson said, “Dr Uysal is studying the geochemistry and isotopes of granites from the basement below the Cooper Basin and observed potential shock lamella in the quartz grains.” Distinctive features of a shock due to a violent event such as a volcanic eruption, meteorite impact or earthquake are preserved in the rock surrounding such an event. In the case of the Cooper Basin impact, “penetrative intracrystalline planar deformation features” – essentially microscopic lines oriented in the same direction – were discovered in quartz grains. Additionally, the magnetic orientation of some of the rocks is slightly altered, further evidence of an impact event.
The impact structure itself may extend 10,000 square kilometers ( 3,850 square miles) and 524 meters (1,700 feet) deep, though Dr. Glikson said that further studies of the area include, “Studies of the geophysical structure of the basement below the Cooper Basin aimed at defining the impact structure.”
There is significant interest in the Cooper Basin as a source of geothermal energy, and there are several oil and gas companies currently mining the region, which is an important on-shore repository of petroleum. The impact event is likely the reason why this region is such a hotspot for geothermal activity.
“Large impacts result in a hydrothermal cell (boiling of ground water) which effect redistribution and re-concentration of K [potassium], Th [thorium] and U [uranium] upwards in the crust, hence elevated generation of heat from crustal zones enriched in the radiogenic elements,” Dr. Glikson explained.
The recent discovery of this impact crater makes it the second largest in Australia, second only to the Woodleigh impact structure (120 km in diameter), which was produced by an asteroid 6 to 12 km (4 to 8 miles) across, about 360 million years ago.
Dr. Glikson and Dr. Uysal will be presenting their findings at the upcoming Australian Geothermal Energy Conference in Adelaide, which runs from the 16th – 19th of November. They also plan to have their results published in a peer-reviewed journal, Dr. Glikson said. You can read a preliminary abstract of their conference paper here.
'Oileán Ruaidh' - the new rock found by the Opportunity rover. It could be another meteorite. Credit: NASA/JPL-Caltech/Cornell University. 3-D by Stuart Atkinson
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The Opportunity rover has done it again — found another strange-looking rock sitting on Meridiani Planum, and it looks like another meteorite. “The dark color, rounded texture and the way it is perched on the surface all make it look like an iron meteorite,” said Matt Golombek from the MER science team. Unofficially named “Oileán Ruaidh” (pronounced ay-lan ruah), which is the Gaelic name (translated: Red Island) for an island off the coast of northwestern Ireland. The rock is about the size of a toaster: 45 centimeters (18 inches) wide from the angle at which it was first seen. Stu Atkinson has posted some enhanced images of the rock on his website, Road to Endeavour, which I have nabbed and posted here. Thanks Stu! The 3-D version above looks awesome with the red/green glasses. And look for more detailed images of the rock on his site soon, as Opportunity comes in for a closer look. UPDATE: As promised, Stu has provided an enhanced close-up of this rock, below.
Close up of a rock on Mars, possibly another meteorite. Credit: NASA/JPL/Cornell, enhanced by Stu Atkinson
Here’s an extreme close-up of Oileán Ruaidh, and it certainly has that “iron meteorite” look about it. It almost looks like the head of a craggy old snapping turtle!
Opportunity's panoramic camera's view of a dark rock that may be an iron meteorite. Image Credit: NASA/JPL-Caltech/Cornell University, enhanced by Stuart Atkinson
The extraction of clean snow from a trench near the CONCORDIA Antarctic station. Image courtesy of J. Duprat CSNSM-CNRS
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Researchers sifting through the pristine, cold snow in Antarctica have found micrometeorites that contain a bit of a surprise. The two micrometeorites, known as particles 19 and 119, contain extremely large amounts of carbon as well as excesses of deuterium. While this high organic content usually comes from distant interstellar space where molecular clouds gather to form new stars, other clues say these space rocks likely formed in our own solar system. This contradicts long-held notions that that all organic matter with extreme deuterium excesses have interstellar origins. Additionally, the meteorites could provide information about the protplanetary disk that formed our solar system.
(A) Backscattered scanning electron micrograph of particle 119. The carbon-rich areas appear dark (arrows); the bright inclusions are dominated by Fe-Ni sulfides and silicates. (B) High-resolution TEM image of particle 19. (C) Bright-field TEM image of particle 19. The lacey carbon film (13) is indicated as black arrows; the crystalline phases are Mgrich olivines (ol), Mg-rich pyroxenes (px), and Fe-Ni sulfides (S); OM, organic matter. Glassy aggregates (GEMS candidates) are highlighted in black squares (13). Image courtesy of Science/AAAS
Jean Duprat and colleagues working at the CONCORDIA polar station located in central Antarctica recovered the two micrometeorites from 40 to 55 year-old snow. In investigating their make-up to determine where they came from, the researchers identified crystalline materials embedded in particles 19 and 119 that indicate that they formed close to our sun, and much more recently than predicted.
Their findings imply that these well-preserved micrometeorites contain a record of the cold regions of our sun’s ancient proto-planetary disk, which eventually led to the formation of our solar system.
More studies of these and other meteorites could possibly reveal details of the first deliveries of organic materials to the primitive Earth.
The findings have been published in this week’s edition of Science.
Christopher and Evan Boudreaux hold the first recovered meteorite from the April 14, 2010 Wisconsin fireball. The first stone was recovered 22 hours after the fall. Credit: Terry Boudreax, shared by Michael Johnson from Rocks From Space
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Via the Astro Bob and Rocks From Space websites comes news that the first meteorite has been recovered from the spectacular fireball that was seen over seven states on April 14, 2010. Brothers Christopher and Evan Boudreaux from southern Wisconsin located a piece of what was likely a meter-wide space rock, according to NASA’ Near Earth Object office. Astro Bob said that pieces of meteorite from Wednesday night’s amazing fireball appear to have fallen over the Livingston, Wisconson area between Platteville and Avoca. If you’re in that area, maybe you’ll have time to do a little meteorite hunting this weekend. But always get permission before going on any private property.
The image above, as well as a close-up of the meteorite, below, are courtesy of Michael Johnson, who hosts the Rocks From Space website Johnson said that according to Mike Farmer, a professional meteorite hunter, the meteorite appears to be an H chondrite.
The first recovered meteorite from the April 14, 2010 fireball. Photo by Terry Boudreaux (c) 2010, via Rocks From Space, used by permission.
Astro Bob indicated there is a meteorite for sale on e-Bay claiming to be from the April 14 fall, but it is not, so beware.
According to NASA’s NEO office, data collected by scientists at NASA’s Marshall’s Space Flight Center in Huntsville, Alabama indicate the parent body of the fireball was not associated with the Gamma Virginids meteor shower, which was taking place at the time the fireball entered the atmosphere. Instead, the small space rock more than likely originated from somewhere in the asteroid belt.
The head of the NEO office, Don Yeomans, said that when the fireball disintegrated high in the atmosphere, it released energy equivalent to the detonation of approximately 20 tons of TNT.
“Knowing the size of this small asteroid helps us determine the frequency of such occurrences,” Yeomans said. “Asteroids this size are expected to enter Earth’s atmosphere about once a month.”
Here’s a mash-up of webcams, dashboard-cams etc. that captured the fireball.
A Murchison meteorite specimen at the National Museum of Natural History in Washington DC.
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New analysis of the famous Murchison meteorite that crash-landed in Australia over 40 years ago shows the space rock contains millions of previously unidentified organic compounds. Researchers say the meteorite, which is over 4.65 billion old – and likely older than our Sun — offers evidence that the early solar system likely had a higher molecular diversity than Earth, and may offer clues to the origins of life on our planet.
Pair of grains from the Murchison meteorite.
Philippe Schmitt-Kopplin from the Institute for Ecological Chemistry in Neuherberg, Germany and his colleagues examined the carbon-rich meteorite with high-resolution structural spectroscopy and found signals representing more than 14,000 different elementary compositions, including 70 amino acids in a sample of the meteorite.
Schmitt-Kopplin said that given the ways in which organic molecules with the same composition can be arranged in space, the meteorite should contain several million different organic chemicals.
The Murchison meteorite landed near a town of the same name in 1969. Witnesses saw a bright fireball which separated into three fragments before disappearing, leaving a cloud of smoke. About 30 seconds later, a tremor was heard. Many specimens were found over an area larger than 13 square km, with individual masses up to 7 kg; one, weighing 680 g, broke through a barn roof and fell in some hay. The total collected mass exceeds 100 kg.
Earlier analysis of the space rock revealed the presence of a complex mixture of large and small organic chemicals.
The meteor probably passed through primordial clouds in the early solar system, picking up organic chemicals. The authors of the paper suggest that tracing the sequence of organic molecules in the meteorite may allow them to create a timeline for the formation and alteration of the molecules within it.
Reports of a possible meteorite impact in Mexico are popping up on various places around the net. Via Twitter, this translated article said a bright light “accompanied by a roar which swayed buildings and houses” was reported in towns in the bordering states of Puebla and Hidalgo, at about 18:30 local time on Wednesday, Feb. 10, and is being attributed to a meteorite. The article includes reports of a bridge collapsing and a 30-meter crater causing “tension among people.”
We’ll confirm if this is an actual meteorite hit as soon as more details become available. The Bad Astronomer has also posted about this, so check his site for updates, too.
Here’s a map of the region where the reports are originating.
A map showing Ahuazotepec Municipality, Puebla, bordering Cuautepec, Hidalgo, Mexico. Credit: Google Maps
So far, no images or video have surfaced of the huge fireball that was reported in the skies over Ireland on February 3, 2010. The Daily Mail posted a video, but it appears to be one from a year ago, maybe earlier. They write that meteorite hunters are on the look-out for fallen space rocks in Ireland, and David Moore of Astronomy Ireland is quoted as saying that meteorites likely landed on Irish soil and not at sea, as many witnesses who saw it along the coast said it was traveling inland.
We’re seeing reports popping up on the internet of a huge fireball spotted over Ireland at around 6pm local time on Feb. 3, 2010. There was a video posted to You Tube which claimed to be footage of the event, but it now seems that was old footage, so we have removed the embedded video. (We’ll post any new verified images or videos when they become available.) Any Irish readers out there see anything? The Irish Times said members of the public throughout the country have been reporting sightings of the fireball. The Times quoted Tommy David Moore from Astronomy Ireland: “A major explosion happened in the sky over Ireland. We think it’s a fireball, that’s a rock from space the earth has slammed into and they burn up as huge shooting stars. This one appears to have lit up the whole country. The phones here in Astronomy Ireland are going crazy.” Continue reading “Huge Fireball Reported Over Ireland”
