Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta

Enhanced Image of Vesta Captured by Dawn on July 9, 2011. NASA's Dawn spacecraft entered orbit around Vesta on July 16, 2011. Dawn obtained the raw image of Vesta with its framing camera on July 9, 2011 - which has been enhanced and annotated. It was taken from a distance of about 26,000 miles (41,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 2.4 miles (3.8 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA. Enhanced and annotated by Ken Kremer

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NASA’s super exciting Dawn mission to the Asteroid Belt marked a major milestone in human history by becoming the first ever spacecraft from Planet Earth to achieve orbit around a Protoplanet – Vesta – on July 16. Dawn was launched in September 2007 and was 117 million miles (188 million km) distant from Earth as it was captured by Asteroid Vesta.

Dawn’s achievements thus far have already exceeded the wildest expectations of the science and engineering teams, and the adventure has only just begun ! – so say Dawn’s Science Principal Investigator Prof. Chris Russell, Chief Engineer Dr. Marc Rayman (think Scotty !) and NASA’s Planetary Science Director Jim Green in exclusive new interviews with Universe Today.

As you read these words, Dawn is steadily unveiling new Vesta vistas never before seen by a human being – and in ever higher resolution. And it’s only made possible via the revolutionary and exotic ion propulsion thrusters propelling Dawn through space (think Star Trek !). That’s what NASA, science and space exploration are all about.

Dawn is in orbit, remains in good health and is continuing to perform all of its functions,” Marc Rayman of the Jet Propulsion Laboratory, Pasadena, Calif., told me. “Indeed, that is how we know it achieved orbit. The confirmation received in a routine communications session that it has continued thrusting is all we needed.”

Image of Vesta Captured by Dawn on July 9, 2011. NASA's Dawn spacecraft obtained this image with its framing camera on July 9, 2011. It was taken from a distance of about 26,000 miles (41,000 kilometers) away from the protoplanet Vesta. Each pixel in the image corresponds to roughly 2.4 miles (3.8 kilometers). Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn entered orbit at about 9900 miles (16000 km) altitude after a nearly 4 year journey of 1.73 billion miles.

Over the next few weeks, the spacecrafts primary task is to gradually spiral down to its initial science operations orbit, approximately 1700 miles above the pock marked surface.

Vesta is the second most massive object in the main Asteroid Belt between Mars and Jupiter. Dawn is the first probe to orbit an object in the Asteroid Belt.

I asked Principal Investigator Chris Russell from UCLA for a status update on Dawn and to describe what the team can conclude from the images and data collected thus far.

“The Dawn team is really, really excited right now,” Russell replied.

“This is what we have been planning now for over a decade and to finally be in orbit around our first ‘protoplanet’ is fantastic.”

“The images exceed my wildest dreams. The terrain both shows the stress on the Vestan surface exerted by 4.5 billion years of collisions while preserving evidence [it seems] of what may be internal processes. The result is a complex surface that is very interesting and should be very scientifically productive.”

NASA's Dawn spacecraft, illustrated in this artist's concept, is propelled by ion engines to Protoplanets Vesta and Ceres. Credit: NASA/JPL

“The team is looking at our low resolution images and trying to make preliminary assessments but the final answers await the higher resolution data that is still to come.”

Russell praised the team and described how well the spacecraft was operating.

“The flight team has been great on this project and deserves a lot of credit for getting us to Vesta EARLY and giving us much more observation time than we had planned,” Russell told me.

“And they have kept the spacecraft healthy and the instruments safe. Now we are ready to work in earnest on our science observations.”

Dawn will remain in orbit at Vesta for one year. Then it will fire its ion thrusters and head for the Dwarf Planet Ceres – the largest object in the Asteroid Belt. Dawn will then achieve another major milestone and become the first spacecraft ever to orbit two celestial objects.

Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

Jim Green, Director of Planetary Science for the Science Mission Directorate (SMD) at NASA HQ in Washington, DC, summed up his feelings about Dawn in this way;

“Getting Dawn into orbit is an amazing achievement,” Green told me.

“Instead of the ‘fire the thrusters full blast’ we just sort of slid into orbit letting gravity grab the spacecraft with a light tug. This gives us great confidence that the big challenge down the road of getting into orbit around Ceres can also be accomplished just as easily.”

Sharper new images from Vesta will be published by NASA in the next day or so.

“We did take a few navigation images in this last sequence and when they get through processing they should be put on the web this week,” Russell informed. “These images are from a similar angle to the last set and with somewhat better resolution and will not reveal much new.”

However, since Dawn is now orbiting Vesta our upcoming view of the protoplanet will be quite different from what we’ve seen in the approach images thus far.

“We will be changing views in the future as the spacecraft begins to climb into its science orbit,” stated Russell.

“This may reveal new features on the surface as well as giving us better resolution. So stay tuned.”

Marc Rayman explained how and why Dawn’s trajectory is changing from equatorial to polar:

“Now that we are close enough to Vesta for its gravity to cause a significant curvature in the trajectory, our view is beginning to change,” said Rayman. “That will be evident in the pictures taken now and in the near future, as the spacecraft arcs north over the dark side and then orbits back to the south over the illuminated side.”

“The sun is over the southern hemisphere right now,” added Russell. “When we leave we are hoping to see it shine in the north.”

Dawn is an international mission with significant participation from Germany and Italy. The navigation images were taken by Dawn’s framing cameras which were built in Germany.

Exploring Vesta is like studying a fossil from the distant past that will immeasurably increase our knowledge of the beginnings of our solar system and how it evolved over time.

Dawn Infographic Poster - click to enlarge. Credit: NASA

Vesta suffered a cosmic collision at the south pole in the distant past that Dawn can now study at close range.

“For now we are viewing a fantastic asteroid, seeing it up close as we zero in on its southern hemisphere, looking at the huge central peak, and wondering how it got there,” explained Jim Green

“We know Vesta was nearly spherical at one time. Then a collision in its southern hemisphere occurred blowing off an enormous amount of material where a central peak now remains.”

That intriguing peak is now obvious in the latest Dawn images from Vesta. But what does it mean and reveal ?

“We wonder what is that peak? replied Green. “Is it part of the core exposed?

“Was it formed as a result of the impact or did it arise from volcanic action?”

“The Dawn team hopes to answer these questions. I can’t wait!” Green told me.

As a result of that ancient south pole collision, about 5% of all the meteorites found on Earth actually originate from Vesta.

Keep your eyes glued to Dawn as mysterious Vesta’s alluring secrets are unveiled.

Dawn Trajectory and Current Location in orbit at Vesta on July 18, 2011. Credit: NASA/JPL

Read my prior features about Dawn
Dawn Closing in on Asteroid Vesta as Views Exceed Hubble
Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

Dawn Closing in on Asteroid Vesta as Views Exceed Hubble

Hubble and Dawn Views of Vesta. These views of the protoplanet Vesta were obtained by NASA's Dawn spacecraft and NASA's Hubble Space Telescope. The image from Dawn, on the left, is a little more than twice as sharp as the image from Hubble, on the right. The image from Hubble, which is in orbit around the Earth, was obtained on May 14, 2007, when Vesta was 109 million miles (176 million kilometers) away from Earth. Dawn's image was taken on June 20, 2011, when Dawn was about 117,000 miles (189,000 kilometers) away from Vesta. The framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd

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A new world in our Solar System is about to be unveiled for the first time – the mysterious protoplanet Vesta, which is the second most massive object in the main Asteroid Belt between Mars and Jupiter.

NASA’s Dawn Asteroid orbiter has entered its final approach phase to Vesta and for the first time is snapping images that finally exceed those taken several years ago by the iconic Hubble Space Telescope.

“The Dawn science campaign at Vesta will unveil a mysterious world, an object that can tell us much about the earliest formation of the planets and the solar system,” said Jim Adams, Deputy Director, Planetary Science Directorate at NASA HQ at a briefing for reporters.

Vesta holds a record of the earliest history of the solar system. The protoplanet failed to form into a full planet due to its close proximity to Jupiter.

Check out this amazing NASA approach video showing Vesta growing in Dawn’s eyes. The compilation of navigation images from Dawn’s framing camera spans about seven weeks from May 3 to June 20 was released at the NASA press briefing by the Dawn science team.

Dawn’s Approach to Vesta – Video

Best View from Hubble – Video

Be sure to notice that Vesta’s south pole is missing due to a cataclysmic event eons ago that created a massive impact crater – soon to be unveiled in astounding clarity. Some of that colossal debris sped toward Earth and survived the terror of atmospheric entry. Planetary Scientists believe that about 5% of all known meteorites originated from Vesta, based on spectral evidence.

After a journey of four years and 1.7 billion miles, NASA’s revolutionary Dawn spacecraft thrusting via exotic ion propulsion is now less than 95,000 miles distant from Vesta, shaping its path through space to match the asteroid.

The internationally funded probe should be captured into orbit on July 16 at an initial altitude of 9,900 miles when Vesta is some 117 million miles from Earth.

After adjustments to lower Dawn to an initial reconnaissance orbit of approximately 1,700 miles, the science campaign is set to kick off in August with the collection of global color images and spectral data including compositional data in different wavelengths of reflected light.

Dawn Approaching Vesta
Dawn obtained this image on June 20, 2011. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/PSI and NASA/ESA/STScI/UMd

Dawn will spend a year investigating Vesta. It will probe the protoplanet using its three onboard science instruments – provided by Germany, Italy and the US – and provide researchers with the first bird’s eye images, global maps and detailed scientific measurements to elucidate the chemical composition and internal structure of a giant asteroid.

“Navigation images from Dawn’s framing camera have given us intriguing hints of Vesta, but we’re looking forward to the heart of Vesta operations, when we begin officially collecting science data,” said Christopher Russell, Dawn principal investigator, at the University of California, Los Angeles (UCLA). “We can’t wait for Dawn to peel back the layers of time and reveal the early history of our solar system.”

Because Dawn is now so close to Vesta, the frequency of imaging will be increased to twice a week to achieve the required navigational accuracy to successfully enter orbit., according to Marc Rayman, Dawn Chief Engineer at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

“By the beginning of August, it will see Vesta with more than 100 times the clarity that Hubble could ever obtain,” says Rayman.

Vesta in Spectrometer View
On June 8, 2011, the visible and infrared mapping spectrometer aboard NASA's Dawn spacecraft captured the instrument's first images of Vesta that are larger than a few pixels, from a distance of about 218,000 miles (351,000 kilometers). The image was taken for calibration purposes. An image obtained in the visible part of the light spectrum appears on the left. An image obtained in the infrared spectrum, at around 3 microns in wavelength, appears on the right. The spatial resolution of this image is about 60 miles (90 kilometers) per pixel. Credit: NASA/JPL-Caltech/UCLA/ASI/INAF

Dawn will gradually edge down closer to altitudes of 420 miles and 120 miles to obtain ever higher resolution orbital images and spectal data before spiraling back out and eventually setting sail for Ceres, the largest asteroid of them all.

Dawn will be the first spacecraft to orbit two celestial bodies, only made possible via the ion propulsion system. With a wingspan of 65 feet, it’s the largest planetary mission NASA has ever launched.

“We’ve packed our year at Vesta chock-full of science observations to help us unravel the mysteries of Vesta,” said Carol Raymond, Dawn’s deputy principal investigator at JPL.

“This is an unprecedented opportunity to spend a year at a body that we know almost nothing about,” added Raymond. “We are very interested in the south pole because the impact exposed the deep interior of Vesta. We’ll be able to look at features down to tens of meters so we can decipher the geologic history of Vesta.”

Possible Piece of Vesta
Scientists believe a large number of the meteorites that are found on Earth originate from the protoplanet Vesta. A cataclysmic impact at the south pole of Vesta, the second most massive object in the main asteroid belt, created an enormous crater and excavated a great deal of debris. Some of that debris ended up as other asteroids and some of it likely ended up on Earth. Image Credit: NASA/JPL-Caltech
Dawn Trajectory and Current Location on June 29, 2011. Credt: NASA/JPL
Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

Read my prior feature about Dawn here

NASA Researchers Find Brand New Mineral in Old Meteorite

A bright field scanning transmission electron microscope (STEM) micrograph showing a Wassonite grain in dark contrast. Credit: NASA

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It’s a brand new mineral, and it’s from space. Researchers taking a new look at an old meteorite with a high-tech electron microscope have found a new mineral, now called Wassonite, in a space rock found in Anarctica back in 1969, the Yamato 691 enstatite chondrite. The meteorite likely originated from the Asteroid Belt between Mars and Jupiter and is about 4.5 billion years old.

“Wassonite is a mineral formed from only two elements, sulfur and titanium, yet it possesses a unique crystal structure that has not been previously observed in nature,” said Keiko Nakamura-Messenger, a NASA scientist who headed the research team.

Wassonite now joins the list of 4,500 official minerals, approved by the International Mineralogical Association. It was named after meteorite researcher John T. Wasson, from the University of California, Los Angeles (UCLA).

But there could be more unknown minerals inside the meteorite. The researchers found Wassonite surrounded by additional minerals that have not been seen before, and the team is continuing their investigations.

The amount of Wassonite in the rock is less than one-hundredth the width of a human hair or 50×450 nanometers wide. Without NASA’s transmission electron microscope, which is capable of isolating the Wassonite grains and determining their chemical composition and atomic structure, the mineral would have been impossible to see.

In 1969, members of the Japanese Antarctic Research Expedition discovered nine meteorites on the blue ice field of the Yamato Mountains in Antarctica. This was the first significant recovery of Antarctic meteorites and represented samples of several different types. As a result, the United States and Japan conducted systematic follow-up searches for meteorites in Antarctica that recovered more than 40,000 specimens, including extremely rare Martian and lunar meteorites.

“More secrets of the universe can be revealed from these specimens using 21st century nano-technology,” said Nakamura-Messenger.

“Meteorites, and the minerals within them, are windows to the formation of our solar system,” said Lindsay Keller, space scientist at NASA’s Johnson Space Center in Houston, who was the principal investigator of the microscope used to analyze the Wassonite crystals. “Through these kinds of studies we can learn about the conditions that existed and the processes that were occurring then.”

For more information see this NASA pdf. which provides more images and details about the Wassonite detection.

Claim of Alien Life in Meteorites Needs Further Review

Image of permineralized remains in the one of the meteorites studied by Richard Hoover. Credit: Journal of Cosmology

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A recent paper published by a NASA scientist claims the discovery evidence of fossil bacteria in a rare subclass of carbonaceous meteorite. The claims are extraordinary, and were the paper published somewhere other than the Journal of Cosmology, (and given an “exclusive preview” on Fox News) more people might be taking this seriously. But, even so, the topic went viral over the weekend.

Titled “Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites” and written by NASA scientist Dr. Richard Hoover of the Marshall Space Flight Center, the paper makes the bold claim that meteorites found in France and Tanzania in the 1800s (the Alais, Ivuna, and Orgueil CI1 meteorites) have clear evidence pointing to space-dwelling microbes, with inferences of panspermia — the theory that microbes brought to Earth in comets and meteorites could have started life on our planet. “The implications,” says an online synopsis of the paper, “are that life is everywhere, and that life on Earth may have come from other planets.”

The paper states: “Filaments found in the CI1 meteorites have also been detected that exhibit structures consistent with the specialized cells and structures used by cyanobacteria for reproduction (baeocytes, akinetes and hormogonia), nitrogen fixation (basal, intercalary or apical heterocysts) and attachment or motility (fimbriae).”

Dr. Chris McKay, a planetary scientist and astrobiologist at NASA Ames Research Center, pointed out to Universe Today that Hoover’s claims are “extraordinary, because of the ecological setting implied. Cyanobacteria live in liquid water and are photosynthetic.”

McKay said finding heterocysts (cells formed by some filamentous cyanobacteria) would certainly be indicative of life from an actively thriving environment. “The implication of these results is that the meteorite hosted a liquid water environment in contact with sunlight and high oxygen,” he told Universe Today in an email.

Several scientists from various fields have written commentaries on this, (see astronomer Phil Plait’s take, biologist PZ Myers (from my alma mater) and microbiologist Rosie Redfield (who refuted the “arsenic life” finding late last year), and there’s tons more about this available, and Alan Boyle at MSNBC’c Cosmic Log is keeping a running update) but everyone seems to agree that verifying that the structures — rods and spheres seen in rock — are actually fossilized bacteria is very difficult to do.

Image at 1000 X of multiple filaments and sheaths embedded in Orgueil meteorite. Credit: Journal of Cosmology

There have been previous reports of bacteria in meteorites, but most have turned out to be contamination or misunderstanding of the microscopic structures within rocks (remember the Alan Hills Meteorite claim from 1996 –which is still widely controversial.) It turns out that Dr. Hoover has reported fossil bacteria previously, but none have actually been proven. And, it also turns out that Hoover’s paper was submitted to the Astrobiology Journal in 2007, but the review was never completed.

“Richard Hoover is a careful and accomplished microscopist so there is every reason to believe that the structures he sees are present and are not due to contamination,” McKay said. “If these structures had been reported from sediments from a lake bottom there would be no question that they were classified correctly as biological remains.”

There are two possibilities, McKay said. “One, the structures are not biological but are chance shapes. In a millimeter square area of meteorite there are million possible 1 micron squares. Perhaps any diversity of shapes can be found if searching is extensive.”

Or the second possibility, McKay said is that “the environments on meteorites are, or were, radically different from what we would expect. There are suggestions for how meteorite parent bodies could have sustained interior liquid water. But not in a way that could have the liquid water exposed to sunlight. It also seems unlikely that high oxygen concentrations would be implied.”

There’s also the question of why Hoover would choose to publish in the somewhat dubious Journal of Cosmology, an open access, but supposedly peer-reviewed online journal, which has come under fire for errors found in some of their articles, and for the rather sensational claims made by some of the papers published within.

But word also was released by the Journal of Cosmology that they will cease publication in May 2011. In a press release titled, “Journal of Cosmology To Stop Publishing–Killed by Thieves and Crooks,” (posted by journalist David Dobbs), the press release said that the “JOC threatened the status quo at NASA,” and that “JOC’s success posed a direct threat to traditional subscription based science periodicals, such as “science” magazine; just as online news killed many newspapers. Not surprisingly, JOC was targeted by science magazine and others who engaged in illegal, criminal, anti-competitive acts to prevent JOC from distributing news about its online editions and books.”

UPDATE: NASA has released a statement on Hoover’s paper, saying that “NASA cannot stand behind or support a scientific claim unless it has been peer-reviewed or thoroughly examined by other qualified experts. This paper was submitted in 2007 to the International Journal of Astrobiology. However, the peer review process was not completed for that submission. NASA also was unaware of the recent submission of the paper to the Journal of Cosmology or of the paper’s subsequent publication. Additional questions should be directed to the author of the paper.” – Dr. Paul Hertz, chief scientist of NASA’s Science Mission Directorate in Washington

But Hoover’s work is generating a huge buzz.

The journal’s editor in chief, Rudy Schild of the Harvard-Smithsonian Centre for Astrophysics, said Hoover is a “highly respected scientist and astrobiologist with a prestigious record of accomplishment at NASA. Given the controversial nature of his discovery, we have invited 100 experts and have issued a general invitation to over 5,000 scientists from the scientific community to review the paper and to offer their critical analysis.”

“No other paper in the history of science has undergone such a thorough analysis, and no other scientific journal in the history of science has made such a profoundly important paper available to the scientific community, for comment, before it is published,” Schild added. Those commentaries will be published March 7 through March 10, and can be found here.

Certainly, further review of Hoover’s work needs to be conducted.

Incoming! New Camera Network Tracks Fireballs

http://science.nasa.gov/science-news/science-at-nasa/2011/01mar_meteornetwork/

How often have you seen a meteor streak across the sky and wondered where it came from and what it was? A new network of smart cameras that NASA is setting up will hopefully help answer those questions for as many fireballs as possible, at least in the US.

“If someone calls me and asks ‘What was that?’ I’ll be able to tell them,” said William Cooke, head of NASA’s Meteoroid Environment Office. With the new camera network, Cooke and his team hope to have a record of every big meteoroid that enters the atmosphere over the certain parts of the U.S. “Nothing will burn up in those skies without me knowing about it!” he added.

And the exciting part is that Cooke is looking to partner with schools, science centers, and planetaria willing to host his cameras.

It is estimated that every day about 100 tons of meteoroids — fragments of dust and gravel and sometimes even big rocks – enter the Earth’s atmosphere. But surprisingly, not much is known about the origin of all this stuff.

Groups of these smart cameras in the new meteor network will be able to automatically triangulate the fireballs’ paths, and special software will be able to compute their orbits.

In other U.S. meteor networks, someone has to manually look at all the cameras’ data and calculate the orbits – a painstaking process.

“With our network, our computers do it for us – and fast,” said Cooke.

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The network’s first three cameras, each about the size of a gumball machine, are already up and running. Cooke’s team will soon have 15 cameras deployed east of the Mississippi River, with plans to expand nationwide.

How can you get involved? Here is the criteria for the locations Cooke is currently looking for:

1. Location east of the Mississippi River
2. Clear horizon (few trees)
3. Few bright lights (none close to camera)
4. Fast internet connection

The smart meteor network uses ASGARD (All Sky and Guided Automatic Realtime Detection) software, developed at the University of Western Ontario, which hosts the Southern Ontario Meteor Network, which took the video at the top of this article. The software processes the visual information and performs the triangulation needed to determine the orbits and origins of the fireballs.

The cameras can also provide information on where any potential meteorites may have landed, which is great for meteorite hunters and scientists. Getting a piece of a space rock is like a free sample return mission.

NASA's Smart Meteor Network is catching more than fireballs. Click on the image to see a movie where a bird stops to rest on one of the cameras in Georgia.

All cameras in the network send their fireball information to Cooke and to a public website. Teachers can contact Cooke at [email protected] to request teacher workshop slides containing suggestions for classroom use of the data. Students can learn to plot fireball orbits and speeds, where the objects hit the ground, how high in the atmosphere the fireballs burn up, etc.

But anyone can try meteor watching on their own, without being part of the network.

“Go out on a clear night, lie flat on your back, and look straight up,” Cooke said. “It will take 30 to 40 minutes for your eyes to become light adapted, so be patient. By looking straight up, you may catch meteor streaks with your peripheral vision too. You don’t need any special equipment — just your eyes.”

Then – if you are lucky to see some bright fireballs — you can check the fireball website to find out more information about what you saw.

Source: Science@NASA

Martian Meteorite Reveals Ancient Water Flows, Methane

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).

Souce: University of Leicester

Researchers Discover 2nd Largest Impact Crater in Australia

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.

Source: Queensland University press release, conference paper abstract, interview with Dr. Andrew Glikson

Oppy’s New Meteorite Find (in 3-D!)

'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

Read more about the rock at JPL’s website.

Antarctic Micrometeorites Provide Clues to Solar System Formation

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.

Meteorite Recovered from April 14 Fireball

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.

Sources: Astro Bob, Rocks From Space, NASA’s NEO office, JPL