News and Updates

10/20/2011

Arizona State University is home to the world’s largest university-based meteorite collection. Consisting of specimens from more than 1,650 separate meteorite falls, today’s ASU Center for Meteorite Studies collection is significantly larger than the almost 700 specimens that seeded the cache 50 years ago. Through careful curation and management, as well as the addition of enviable analytical capabilities, the collection blossomed and the center evolved into an intellectual hub for research on meteorites and other planetary materials.

It was 1958, when Arizona State College became Arizona State University. Accompanying the name change was the goal of strengthening the research activities of the young university. Research coordinator George A. Boyd, tasked with bolstering the research program, played an important role in bringing meteorite research to ASU.

Two separate events helped lead ASU down the path of meteorite research. First, the Soviet Union launched Sputnik in October 1957, putting space at the forefront of American consciousness. Second, Harvey H. Nininger, the famous meteorite hunter and self-taught meteoriticist, sold a portion of his collection to the British Natural History Museum in 1958. The sale marked a loss for the state, as the museum housing Nininger's extensive collection had been originally located near Barringer Meteorite Crater in northern Arizona and then, later, in Sedona, Arizona.

Boyd was familiar with Nininger's collection and recognized its importance to both Arizona and to ASU's pursuit of research in an up-and-coming discipline. Boyd, working with the chair of ASU’s chemistry department, Clyde A. Crowley, and ASU President Grady Gammage, solicited a grant from the National Science Foundation (NSF) to purchase the remainder of Nininger's collection and bring it to ASU. To strengthen its proposal, ASU offered supporting funds from both the ASU Foundation and Herbert G. Fales, the vice president of International Nickel Company, who was familiar with Nininger through his own interest in meteorites.

The NSF recognized the importance of keeping the remainder of Nininger's collection in the United States and accepted ASU’s proposal on June 8, 1960.

“This was always in the plans and wishes of Nininger that we got the collection from him,” explains ASU Emeritus Professor Carleton B. Moore, founding director of the center.

Recruiting Moore to ASU was a well-researched, multi-step process. Boyd and George M. Bateman, the chair of the division of physical sciences, initiated the search for a director responsible for curating, managing and studying the collection. They consulted with Harrison S. Brown, a geochemistry professor at the California Institute of Technology, who was one of the few scientists in the nation actively studying meteorites, to find a worthy candidate. Brown was also familiar with Nininger and his collection; he had obtained samples for study from Nininger and had also visited Nininger's museums with his students. Brown recommended one of those students, Moore, for the directorship. Acting on behalf of ASU, Fales flew to Wesleyan University where Moore was teaching at the time, to recruit him. Moore agreed to take the position.

In spring 1961, the initial activities of the Center for Meteorite Studies, christened by new ASU President G. Homer Durham, commenced at ASU under the direction of Moore.

“When I came there were very few of us that knew anything about meteorites,” says Moore, who was 29 years old when he began his career at ASU. “At that time, it was mostly chemists who studied meteorites.”

In keeping with the fact that the most well-established scientists studying meteorites at the time were chemists, the care of the collection and promotion of its study was designated to ASU’s chemistry department.

“In the beginning, we just had a small room in the C-wing basement and everything was in steel cases; that’s where they put the meteorites before I came. And then chemistry abandoned a lecture room between the C wing and the B wing and we were given part of that for the meteorites,” says Moore. “We eventually moved again to where the vault is now.”

One of the NSF grant’s stipulations required that ASU would make specimens available to researchers around the world. Many worried that the new university would buckle under the demands, and the collection might be lost. To allay concerns, the NSF required the center to have an oversight advisory committee that consisted of representatives appointed by the National Academy of Sciences, NSF, Smithsonian, state of Arizona and American Museum of Natural History.

“Many in big schools weren't sure a place like ASU could take care of the specimens. They thought it was crazy sending this valuable meteorite collection here,” explains Moore.

Moore and his team successfully demonstrated that it was indeed possible to provide research materials to qualified users without degrading the collection. Since then the center has become a model for museums, which previously merely displayed meteorites, to follow suit and open their collections freely for research pursuits.

Peter Buseck, now a Regent’s Professor in ASU’s School of Earth and Space Exploration, was among the first ASU professors to actively put the center’s collection to use for scientific study. His diverse research portfolio has contained meteorite-related topics since soon after his arrival at ASU in 1963, and has involved dozens of students and postdoctoral researchers who contributed and continue to contribute significantly to meteorite science.

Bringing the Moon to ASU

Over the years, under the watchful eye of Moore, the collection grew exponentially through purchases, exchanges and donations.

The center’s own research reputation also flourished under Moore’s direction. Moore himself played a leading role in ASU’s efforts of building up the young university’s research portfolio, acquiring 35 research grants in materials science and geology from NASA, NSF and the U.S. Geological Survey from 1963-1987.

“I went to a meeting of meteorite curators in London in 1962 and there Howard Axon encouraged me to be interested in carbon,” says Moore. “This led me to be in the first groups to unambiguously identify amino acids in the Murchison and then Murray meteorites.”

Moore not only analyzed carbon in meteorites but in other types of extraterrestrial specimens as well.

The experience and success of the center's team in studying meteorites led to Moore’s inclusion on the team of scientists assigned to analyze Moon rocks returned from 1969 to 1972 by Apollo astronauts. At that time, the center was the only facility with proven analytical capabilities in place for measuring the low abundances of carbon and other volatile elements in rocks, so Moore flew to Houston to pick up the Apollo 11 samples and brought them back to ASU for analysis. These analyses, along with discussions with Jack Larimer, who was hired by the center with a joint appointment in ASU’s geology department, helped Moore and his team understand the sources of lunar carbon. The ASU team ultimately analyzed more than 200 lunar samples.

This work bolstered the reputation of the center as a research facility, and also set the stage for the study of other types of planetary materials by ASU researchers in the future.

“I hired Ron Greeley, who in turn hired Phil Christensen,” says Moore. “The center really did what it was supposed to – it started all this space research.”

Yielding major scientific contributions was not the center’s only focus. Since its inception, the center has focused on educational and public outreach activities. In 1967, the center opened a museum in the Bateman Physical Sciences C-wing.

“Chemistry expanded and that gave us meteorite space so Chuck Lewis and I made that little museum,” says Moore. The museum initiated by Moore is still in operation, but the majority of meteorites are catalogued and stored in a secure room, in boxes, on shelves and in drawers. “Outreach is not new; we’ve been doing it for a long, long time.”

The next generation

After more than 40 years of dedicated service, Moore retired from ASU in 2003 but to this day he actively participates in the center’s education and public outreach activities, and numerous public speaking engagements that reach hundreds of educators, students and members of the public each year.

“The number of specimens in the collection never went down,” says Moore. “It was part of the obligation: We should never lose anything, we should never waste anything.”

Former NASA administrator Laurie Leshin was a professor in the ASU department of geological sciences and an ASU alumna, when she was named the new director after Moore retired. In 2006, Meenakshi “Mini” Wadhwa, then curator of meteoritics at The Field Museum of Natural History in Chicago, was named director of the center and professor in the School of Earth and Space Exploration in ASU’s College of Liberal Arts and Sciences.

Through careful management and grants and contributions, ASU’s meteorite collection has prospered and has lived up to all the hopes and aspirations expressed when it was established. Today, the collection is actively used for geological, planetary, and space science research at ASU and throughout the world. There’s every reason to predict that the center will continue to build upon it enviable reputation.

 

Caption: Carleton Moore served as the first director of ASU’s Center for Meteorite Studies. His research on lunar samples acquired from NASA’s Apollo missions in the 1970’s were particularly well-publicized and set the stage for significant work in planetary geology and astrophysics by subsequent ASU faculty. Photo by: University Archives Photographs, Arizona State University Libraries

 

(Nikki Cassis)

 

 

10/20/2011

Meteorites in Arizona State University’s Center for Meteorite Studies have names ranging from Abbott to Zmaitkiemis, representing samples collected from every part of the world, each associated with a unique anecdote or distinctive fact. As well as a treasury of useful and interesting rocks, the center contains a cache of fascinating stories that span decades and the globe.

Beginning with a purchase of almost 700 samples from amateur meteorite hunter H. H. Nininger in 1960, the collection has grown by way of purchases, exchanges, and gifts, and now contains in excess of 10,000 samples from more than 1,650 different meteorite falls.

The treasures stored in the meteorite vault delight many senses. Some samples are smooth, others are rough. They come in all shapes and sizes and possess interesting traits. The largest is a 550-kilogram sample called Bondoc that came from a meteorite that originally weighed close to one ton. Some meteorites are black or brown, others are reddish, and a few are green. Johnston, an achondrite meteorite, contains the mineral orthopyroxene that gives it a gorgeous light green hue. One meteorite even has a smell; Murchison, which fell in Australia in 1969, contains 4.5 billion year old sulfur-rich organic compounds that give the rock its distinctive odor.

Carleton Moore, the center’s founding director, chose to organize the samples in a unique way.

“At most places, like the Smithsonian, the meteorites are sorted alphabetically, but I arranged them by types,” says Moore. “If you come in and you want to see, say, achondrites, they’re all together, so you don’t have to run around to find them.”

Scientists sort meteorites into three main groups: stony, iron, and stony iron. The most common type is the stony meteorite, and the most common type of stony meteorite is called a chondrite.

“Among the chondrites [in our collection], one of the most amazing ones is from Arizona, the Holbrook meteorite, which fell in 1912, east of Holbrook, Arizona,” says Moore.

Because somebody saw the Holbrook meteorite fall to earth rather than just finding them without witnessing the shower, the Holbrook samples are classified as a fall, not a find. Falls produce more pristine samples than finds, which makes them more valuable for research.

The Holbrook meteorite is just one member of an extensive collection of Arizona meteorites. Another is Canyon Diablo, the nickel-iron meteorite responsible for forming Meteor Crater.

Most meteorites found on Earth come from the asteroid belt, but some from the Moon and Mars exist as well. These rare samples constitute a small but important part of the center’s collection.

ASU’s first meteorite from Mars was the Nakhla meteorite, a sample from ASU’s initial acquisition. The center was unaware of its unique origin until research in the 1980s showed that gases trapped in certain rare meteorites (similar to Nakhla) matched those in Mars’ atmosphere, and the CMS could boast its first meteorite from Mars. Other martian meteorites in the center’s collection include pieces of the historical falls of Shergotty, a 5 kilogram (11 pound) sample that fell in Sherghati, India, in 1865, and Zagami, a 18 kilogram (40 pound) sample that fell in the Katsina province of Nigeria in 1962.

One of the center’s most historically important meteorites is L’Aigle, a chondrite which fell in France in 1803. This shower of thousands of stones from the sky finally convinced people that meteorites fall from space. France was also where Ensisheim was found, another chondrite meteorite that fell in 1492 and that represents the second oldest meteorite recovered from a witnessed and recorded fall.

Moore’s favorite meteorite is called Kediri and, although the sample is neither from the Moon nor Mars, it does have a special connection to ASU and to Moore.

In 1972, a Dutch scientist from the University of Nijmegen, to whom Moore had lent meteorite samples in the past, contacted Moore about P. J. Maureau, a Dutch physician who was trying to find a home for a meteorite sample in his possession. Moore expressed interest, and began corresponding directly with Dr. Maureau.

Through a series of letters, Maureau related the meteorite’s story to Moore. In 1940, a friend of Maureau’s witnessed a meteorite fall while on his rubber plantation in Java, Indonesia, and collected about 70 pieces from the shower. He kept the largest, which he later gave to Maureau as a gift when he saw his friend’s interest.

The meteorite’s sale took more than a year, as the Dutch government learned about the sample and wanted to keep a large portion of it in a national museum. Thanks to Maureau’s persistence, the sample finally came to the CMS in 1973.

Maurea’s health was deteriorating when he first contacted Moore, and he died of stomach cancer two years later. When the sale was finally completed, Moore received letters from Maureau’s wife and son that expressed how much the successful transfer of the meteorite meant to Maureau.

“He loved this rock so much, he wanted it to go to a nice home,” says Moore. “And he identified us, ASU, as the nice home.”

Now home to a vast array of meteorites, the center lends its samples to scientists throughout the world, playing a pivotal role in preserving meteorites for current and future study. Specimens are carefully stored in archival quality materials and particularly delicate meteorites are housed in climate-controlled storage to maintain ideal conditions so they are preserved for future generations.

“Every year, chemists and geologists and physicists come up with new techniques to study meteorites, and we have to make sure that some of these meteorites are around for 500 or more years,” says Moore. “This is a tremendous obligation for ASU. Down the road, someone might want to see that meteorite.”

The center is constantly growing its collection in support of its research and education mission. Laurence Garvie, the center’s collection manager, is actively involved in the classification of newly discovered meteorites, portions of which are then archived in the center’s collection. Other new specimens are acquired through purchases as well as exchanges with other institutions, museums and meteorite collectors. Among the more important recent acquisitions are some rare meteorites such as Isheyevo, El Gouanem, and Red Canyon Lake.

“Each one of our meteorites has a story to tell,” says Meenakshi Wadhwa, the center’s current director. “There are certainly very interesting stories about how they were found and how they eventually made their way to our collection. But there are also more ancient stories that these meteorites tell us about the beginnings of our solar system and planets that are only revealed through careful analyses in laboratories like those at ASU.”

 

Caption: This rare meteorite, named Losttown, possesses a well developed Widmanstätten pattern. It is one of the many unique treasures housed in the ASU Center for Meteorite Studies collection. Photo by: Laurence Garvie/Arizona State University

Link to meteorite photo gallery: http://asunews.asu.edu/20111021_gallery_meteoritecollection

(Victoria Miluch)
 

10/18/2011

Astronomy is the study of far away things, the gazing into great distances and the observation of phenomena invisible to the unaided eye. Sangeeta Malhotra, ASU professor of astronomy in SESE, is looking even further than most astronomers, finding and studying galaxies that, until recently, were too distant to detect.

For Malhotra, choosing to study astronomy was a process of narrowing down a very broad interest in how the world works. Malhotra remembers learning about stars and planets in kindergarten, and later becoming fascinated by the elegance of physics in middle school.

“I was interested in many things at any given time. I was interested in biology, genetics, I loved chemistry labs. Physics was my first love, of course. And astronomy was fun,” says Malhotra. She studied physics for her undergraduate and master’s degree in India and, when she applied to graduate schools in the U.S., she chose to concentrate on astrophysics.

Since 1998, Malhotra’s main research focus has been finding and studying distant galaxies. Galaxies started forming within one billion years after the Big Bang, and their formation changed the universe in a fundamental way. Scientists think they released a great amount of light and ionized the hydrogen in the universe. Studying these galaxies allows astronomers to find out the nature of the first generation of galaxies, figure out when they started forming, and when they existed in sufficient numbers to start ionizing hydrogen. The research also advances knowledge about the process of galaxy formation.

One of the methods for finding these galaxies was proposed in 1967, but the theory didn’t translate into practice until thirty years later. In 1998, Malhotra and her collaborator, James Rhoads, also a professor at ASU, thought they might try it themselves, using new technologies.

“Much of it was the instruments. The new wide-field cameras made it much easier. The other thing is to be crazy enough to try something that had been failing for thirty years,” laughs Malhotra.

Malhotra uses some of the largest telescopes in existence to study these galaxies. Although new instruments made the process possible, they didn’t make it easy. “A typical search would consist of us going to a telescope, the Magellan telescope in Chile, for example, and spending five to six nights imaging the same patch of sky through a special filter. After that, it takes typically six months to one year analyzing those images, removing instrumental artifacts, and combining various data. In a typical image, we see about 10,000 sources, and we’d have to select the odd half a dozen sources that are interesting. So talk about needles in a haystack,” says Malhotra.

The first survey Malhotra and Rhoads undertook was for galaxies at 1.3 billion years after the Big Bang, and the next was 0.9 billion years after the Big Bang, which means it’s 12.5 billion light years away. The current survey forms the foundation for award-winning thesis by V. Tilvi, and searches for the most distant galaxies known.

Malhotra says that her curiosity in these galaxies stems from an interest in how we came to exist here today. “To me, formation of galaxies is the first step in formation of stars, and the sort of thing that leads to us being here, talking. If you found yourself stranded on a deserted island, wouldn’t you want to know where you came from? It’s also a challenge: what [poet Robert Browning] said: ‘Oh that a man’s reach should exceed his grasp, or what’s a heaven for?’”

(Victoria Miluch)
 

10/13/2011

School of Earth and Space Exploration mission portfolio includes Moon, Mars, Mercury, asteroid

Arizona State University is no stranger to space exploration missions. Whether to Mars or other solar system targets, its involvement with NASA planetary exploration began in the 1970s and at present, professors and researchers from ASU’s School of Earth and Space have instruments on board or play a significant role with six NASA missions and one European Space Agency (ESA) mission. Others are in the wings.

Mars Launching Pad
ASU began exploring space as an outgrowth of research on meteorites and cosmochemistry. Mars became a prime area of research starting with the arrival in 1977 of professor Ronald Greeley from NASA Ames Research Center. He established the Mars Surface Wind Tunnel facility and was on the flight team for Viking, a Mars mission with two landers and two orbiters.

Courses on the geology of the Moon and Mars followed, as Mars-interested researchers joined the faculty, among them Philip Christensen. Computerized image processing for remote sensing began in the early 1980s, making ASU one the first universities strongly involved in the field, which was previously dominated by NASA’s Jet Propulsion Laboratory and the U.S. Geological Survey.

Then two ASU-designed instruments – Christensen’s long-wave infrared Thermal Emission Spectrometer (TES) and a visual camera by former ASU geological sciences professor Michael Malin – were selected by NASA for its Mars Observer missions. Having two instruments from a single university on a major mission was largely unprecedented at the time. When Mars Observer failed upon arrival in 1991, NASA felt both instruments were so important that they were rebuilt and reflown successfully in 1996 on the Mars Global Surveyor mission.

Following up on this success, NASA launched the Mars Odyssey orbiter in 2001 to determine the composition of the planet’s surface, to detect water and shallow layers of ice, and to study the radiation environment. The orbiter holds the record for the longest-operating Mars spacecraft.

Christensen serves as the principal investigator for Mars Odyssey’s Thermal Emission Imaging System (THEMIS) instrument, a multi-band infrared and visual camera that helped develop the most accurate global map of Mars ever. ASU associate professor Alberto Behar and professor Jim Bell are investigation scientists for the same instrument.

For NASA’s twin Mars Exploration Rovers, Spirit and Opportunity, Christensen redesigned his TES infrared spectrometer making it smaller. Each rover was outfitted with one of these “Mini-TES” instruments to aid in the identification of promising rocks and soils for closer examination. Bell is principal investigator of the rovers’ main optical imagers, the Panoramic Cameras (or Pancams) and Greeley served as a member of the rover science flight team.

ASU’s Mars foothold widened in 2003 with the launch of ESA’s Mars Express orbiter, on which Greeley is a co-investigator on the High Resolution Stereo Camera team. ASU’s involvement increased again in 2006 when NASA’s Mars Reconnaissance Orbiter began to search for evidence for persistent water on Mars. Bell serves as a science team member for both color and black and white imaging systems.

A School for Explorers
With Mars and solar system exploration growing, in 2006, ASU’s School of Earth and Space Exploration was born through the interdisciplinary combination of the department of geological sciences with astronomy and astrophysics researchers and students from what had been the department of physics and astronomy. An academic unit of the College of Liberal Arts and Sciences, the school acts as the focus for systems engineering research and education at ASU as it relates to space and Earth science.

“SESE (pronounced see-see) was built to be an internationally recognized center for exploration activities on Earth and in space,” says founding director Kip Hodges. “As part of this mission, we will be at the leading edge of robotic exploration and engaged in efforts to re-energize America’s human exploration efforts. I foresee an increasing role for universities in space exploration, and you can be sure that SESE will be at the front of the pack.”

In Focus: Mercury, the Moon, asteroids

Via the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) mission, ASU is involved with the small rocky planet of Mercury. After flybys of Earth, Venus and Mercury, MESSENGER started a yearlong study of its target planet in March 2011. Professor Mark Robinson, a member of the camera team, was involved with creating the first global mosaic of the planet.

Robinson is also studying the Moon with NASA’s Lunar Reconnaissance Orbiter, where he is principal investigator for LROC, the Lunar Reconnaissance Orbiter Camera. He is joined in efforts by Bell, a science team member on the mission.

While many space missions go to Earth’s nearest neighbors, some go farther afield. NASA’s Dawn mission, launched in 2007, carries a suite of instruments to image the surface, measure reflected and emitted radiation, and measure the gravity field of two massive asteroids, Vesta and Ceres. These orbit between Mars and Jupiter.

David Williams, a faculty research associate in the School of Earth and Space Exploration, is a participating scientist on Dawn. Williams, a planetary volcanologist who has worked on NASA’s Magellan and Galileo probes imaging Venus and Jupiter, intends to study the geological history of these asteroids.

Right Around the Corner

With the launch of NASA’s Mars Science Laboratory (MSL) rover, dubbed Curiosity, just a few weeks away (the launch window opens Nov. 25), excitement is building at ASU.

If all goes according to plan, the Mini-Cooper-size rover is scheduled to land at Gale Crater on Mars next year in August. Carrying an advanced suite of scientific instruments, Curiosity will explore a gigantic “history book” in the form of sedimentary deposits in Gale, seeking evidence of Mars’ past and present habitability.

ASU professors and researchers from the School of Earth and Space Exploration, as well as graduates, are involved in the mission. Professor Meenakshi Wadhwa is a co-investigator with the Sample Analysis at Mars (SAM) instrument, essentially an analytical chemistry system. Amy McAdam, an alumna, is also working on SAM. Professor Jack Farmer is a science team member for a different instrument, CheMin, designed to examine the chemical and mineralogical properties of rocks and soils. And professor Behar is an investigation scientist for the Russian Dynamic Albedo of Neutrons instrument.

Curiosity’s Mars Hand Lens Imager (MAHLI) also has ties to ASU. MAHLI is mounted on its robotic arm and will make close-up images of Mars rocks to help determine past environmental conditions. Kenneth Edgett, an ASU alumnus, is the principal investigator on the MAHLI team. MAHLI comes from Malin Space Science Systems, a company started and operated by former ASU geological sciences professor Malin.

Malin is also the principal investigator for two other MSL cameras, the Mars Descent Imager (MARDI) and Mastcam. And ASU’s professor Bell is an important player regarding the targeting and interpretation of images recovered from all of these camera systems.

Sampling an Asteroid
Another asteroid mission involving ASU is NASA’s OSIRIS-REx. This mission, scheduled for a 2016 launch, is expected to return the first rock and soil samples from asteroid 1999 RQ36 to Earth in 2023. Christensen designed a mineral scouting instrument for OSIRIS-Rex, dubbed OTES (short for OSIRIS-REx Thermal Emission Spectrometer). This instrument, about the size of a cantaloupe, is a modified version of Christensen’s highly successful Mini-TES instrument carried by both Mars Exploration Rovers.

OTES will be the first major scientific instrument completely designed and built on campus at ASU for a NASA mission. This landmark effort will be enabled by completion next summer of the new Interdisciplinary Science and Technology Building IV, a flagship facility to accommodate a new age of exploration. In addition to researchers and students from across the university, the building will house the headquarters for the School of Earth and Space Exploration and many of its faculty research teams. An exciting aspect of the new building will be interactive displays and a high-definition, 3D-theater on the first floor, designed for exploration by the public. Viewing windows will allow visitors to see into the environmentally controlled laboratory facilities where the OTES instrument is being built.

“In the past,” says Christensen, “instruments we’ve designed for NASA were built at an aerospace company in California. With OTES, for the first time complicated space hardware will be built right here on the ASU campus. This is a major step forward for ASU – I can count on one hand the number of universities that can do this.”

Says the school’s director Hodges, “Even as we celebrate our past accomplishments and current success stories, we are focusing our efforts on designing and preparing for future space missions.”

Link to ASU story package

ASU in Space photo gallery

Planetary Rock Stars photo gallery

Artwork by Chris Capages

(Nikki Cassis)

10/12/2011

For 50 years the Center for Meteorite Studies at Arizona State University has served as the intellectual hub for research on meteorites and other planetary materials. It is a place where scientists can conduct critical inquiries into the origin and evolution of the solar system and planets. Home to the world’s largest university-based meteorite collection, the center has educated generations of students, researchers, scholars and the public on meteorites. To commemorate the 50th anniversary, the center will hold a series of special events Oct. 21 on ASU’s Tempe campus.

“We are delighted for this opportunity to share the center’s accomplishments over the past 50 years and our vision for the next era of scholarship in meteorite studies. And we are honored that so many colleagues, friends and supporters of the center will be joining us for a celebration of the past, present and future of meteorite science,” says Meenakshi “Mini” Wadhwa, director of the Center for Meteorite Studies and a professor in the School of Earth and Space Exploration in ASU’s College of Liberal Arts and Sciences.

To celebrate this anniversary, the center will host a day-long symposium on “Meteoritics and Cosmochemistry: Past, Present and Future” on Oct. 21. This will feature talks by prominent researchers and scholars in the field. It will be followed by an evening lecture.

Timothy McCoy, curator-in-charge of the meteorite collection at the Smithsonian National Museum of Natural History and participating scientist on NASA’s Dawn mission, will speak on “Dawn: A Journey to the Birth of the Solar System,” in the Carson Ballroom at Old Main at 7 p.m. This is a free event, open to the public; however, a ticket will be required for entry to the lecture. Free tickets are available at http://cmsanniversary.eventbrite.com.

After the lecture, the public is invited to participate in telescope viewing, a hands-on meteorite display and more space-related fun for the whole family at the School of Earth and Space Exploration astronomy open house. The evening activities take place on the roof of Bateman Physical Sciences H-wing (http://www.asu.edu/map/interactive/?campus=tempe&building=PSH), a short walk from Old Main.

ASU has long been a trailblazer in the study of meteorites, chunks of space rocks that fall to Earth. In the spring of 1961, the initial activities of the center commenced under the direction of geochemist Carleton Moore. Along with a steady stream of world-renowned meteorite scientists brought in by Moore, the center's team of researchers immediately engaged in analyzing specimens in the collection and acquiring additional ones.

Originally created for scientific research on meteorite samples, the center grew to be a hub for the study of all types of extraterrestrial specimens. Prior to the Apollo Moon landings, meteorites supplied the only extraterrestrial materials available for study, providing valuable insights into the origins of our planets and our solar system.

The experience and success of the center's team with studying meteorites led to Moore’s inclusion on the team of scientists assigned to analyze lunar samples returned from 1969 to 1972 by the Apollo astronauts. At that time, the center was the only facility with proven analytical capabilities in place for measuring the low abundances of carbon and other volatile elements in rocks, so Moore flew to Houston to pick up the Apollo 11 samples and brought them back to ASU for analysis. He and his team ultimately analyzed more than 200 lunar samples.

The analyses of Apollo samples not only bolstered the reputation of the center as a research facility, they also set the precedent for the study of other types of planetary materials by ASU researchers in the future.

Today the center houses specimens representing more than 1,650 separate meteorite falls – including several meteorites from Mars and the Moon. The collection is actively used for geological, planetary, and space science research at ASU and throughout the world.

“From its inception, the center has been at the forefront of meteoritic and planetary science research and our goal is to continue to be a leader in this multidisciplinary field,” says Wadhwa. “The wonderful thing about the science of meteorites is that it brings together a lot of different sciences – chemical, physical and biological sciences – to try to understand the beginnings of our solar system and planets, and possibly also the beginnings of life on our planet,” she explains.

“We have incredibly rich resources here at the center, including our meteorite collection, our highly experienced staff, and our analytical capabilities that are among the best in the world,” Wadhwa says. “We are one of but a few places that have successfully brought together all of these elements towards fostering a great environment for cutting-edge research and education in this field.”

Spacecraft sample return missions (e.g., Genesis, Stardust, and the soon to be launched OSIRIS-REx asteroid mission) have provided opportunities for studying samples from more places in the solar system than ever before.

“The future is having access to new kinds of planetary materials,” says Wadhwa, “but also developing the tools and techniques to conduct new and better analyses in the laboratory and remotely by spacecraft, which is one of the goals of the School of Earth and Space Exploration.”

“The new materials, including new samples returned from other places in our solar system, and analytical tools that will be available in the near future will revolutionize our understanding of the solar system and our place in it,” she continues. “This is really a very exciting time in the planetary sciences.”

The next major event for the Center for Meteorite Studies is a move to the new Interdisciplinary Science and Technology Building IV (ISTB IV) on the ASU Tempe campus in the spring of 2012. ISTB IV will house the center's offices, meteorite preparation labs, a state-of-the-art collection storage vault and expanded gallery space for public viewing. This venue will serve as a launching pad for the next 50 great years of the ASU Center for Meteorite Studies.

For more information visit: http://meteorites.asu.edu/cms50

 

(Nikki Cassis)
 

10/10/2011

ASU researchers develop new method to learn about Earth’s largest mass extinction event

Earth’s largest mass extinction event, the end-Permian mass extinction, occurred some 252 million years ago. An estimated 90 percent of Earth’s marine life was eradicated. To better understand the cause of this “mother of all mass extinctions,” researchers from Arizona State University and the University of Cincinnati used a new geochemical technique. The team measured uranium isotopes in ancient carbonate rocks and found that a large, rapid shift in the chemistry of the world’s ancient oceans occurred around the extinction event.

The mechanism of the end-Permian mass extinction has been much debated. One proposed cause for the extinction, the release of toxic hydrogen sulfide gas, is directly related to oceanic anoxia, which is a depletion of dissolved oxygen from the ocean.

Widespread evidence exists for oceanic anoxia before the extinction, but the timing and extent of anoxia remain unknown. Previous hypotheses posited that the deep ocean was depleted of oxygen for millions of years before the end-Permian extinction. The new research using measurements of uranium isotopes in ancient carbonate rocks indicates that the period of ocean-wide anoxia was much shorter.

“Our study shows that the ocean was anoxic for at most tens of thousands of years before the extinction event. That’s much shorter than prior estimates,” says Gregory Brennecka, the lead author of the study and a graduate student in ASU’s School of Earth and Space Exploration in the College of Liberal Arts and Sciences.

Brennecka, working in Professor Ariel Anbar’s research group, conducted the analysis of the samples. Anbar is a professor in ASU’s School of Earth and Space Exploration and the Department of Chemistry and Biochemistry. Achim Herrmann, a senior lecturer at Barrett, the Honors College at ASU, and Thomas Algeo of the University of Cincinnati, who collected the samples in China, helped guide the selection of samples and interpretation of data.

The team studied samples of carbonate rock from Dawen in southern China for uranium isotope ratios (238U/235U) and thorium to uranium ratios (Th/U). The study presumes that carbonate rocks capture 238U/235U and Th/U of the seawater in which they were deposited. If so, they can be used to study changes in the chemistry of ancient oceans. In separate, related work, the team is testing the limits of this assumption.

In a section of rock spanning the time of the extinction, the team found a marked shift in 238U/235U in the carbonate rocks immediately prior to the mass extinction, which signals an increase in oceanic anoxia. The team also found higher Th/U ratios in the same interval, which indicate a decrease in the uranium content of seawater. Lower concentrations of uranium in seawater also serve as signals of oceanic anoxia.

These decreases in 238U/235U and increases in Th/U only occur at the section of rock that contains the end-Permian extinction horizon. This shows that a period of oceanic anoxia existed only briefly prior to the mass extinction, rather than the previously hypothesized much longer timeframe.

The team’s findings represent an increase in knowledge about the ocean’s chemistry at a critical period of the Earth’s history. “This technique gives us a better understanding of how ocean chemistry can change over time, and how sensitive it is to certain environmental factors,” says Brennecka.

The implications of the new geochemical tool the researchers developed are just as important as the study’s findings.

Uranium isotope ratios have been utilized to study the ocean’s chemistry before, but only in black shale, a different and less common type of rock. This study represents the first time uranium isotope ratios have been studied in carbonates for paleo-redox purposes, which is a promising new geochemical tool for future research.

“One of the important outcomes of this study is that we were able to quantify the relative change in the amount of oceanic anoxia across the extinction event in the global ocean. Previous studies were only able to show whether anoxic conditions existed or not. We can now compare this event to other events in Earth history and develop a better understanding of how the amount of oxygen in the Earth’s ocean has changed through time and how this might have affected marine diversity,” says Herrmann.

Carbonates are much more widespread than black shales on Earth through space and time. “By focusing on carbonates we can study ancient anoxic events in many more places and times,” says Anbar. “This was our major motivation in developing the uranium isotope technique.”

It is only recently that researchers have developed the ability to precisely measure slight variations in uranium ratios, largely due to research completed at ASU. Most of the team’s research in this study was conducted at ASU. The study samples were analyzed at ASU’s W. M. Keck Foundation Laboratory for Environmental Biogeochemistry.

“Over the past decade, my research group has worked with many collaborators to develop new techniques to study changes in oxygen in the Earth’s ocean through time,” says Anbar. “We are especially interested in the connections between ocean oxygenation and biological evolution. The uranium isotope technique is the newest method. We expect it will be very useful. This study shows that it is yielding insights pretty quickly.”

“It is exciting to be here, because most of the development work to measure uranium isotopes was done at ASU over the past five years. It is exciting to be at the forefront of these advancements,” says Brennecka.

The team’s results will be published in the Proceedings of National Academy of Sciences Oct. 10 in a paper titled, “Rapid expansion of oceanic anoxia immediately before the end-Permian mass extinction.”

 

Image 1: ASU graduate student Greg Brennecka stands in the W.M. Keck Foundation Laboratory for Environmental Biogeochemistry at ASU in front of the powdered carbonate rock samples collected in Dawen, Southern China. These samples are prior to chemical processing to ready for measurement on the mass spectrometer. There were about 40 samples total for this study. Credit: P.S. Noonan

 

Image 2: The research team analyzed carbonate rock samples collected from the Dawen Permian-Triassic boundary section located on the Great Bank of Guizhou, a carbonate platform in China's Guizhou Province. Uranium isotopes measured in these ancient rocks showed that the world's oceans experienced a rapid shift toward strongly oxygen-deficient conditions at the time of the end-Permian mass extinction. Credit: Tom Algeo

 Victoria Miluch & Nikki Cassis

10/07/2011

A map of the Moon combining observations in visible and ultraviolet wavelengths shows a treasure trove of areas rich in Titanium ores. Not only is titanium a valuable element, it is key to helping scientists unravel the mysteries of the Moon’s interior. Arizona State University’s Mark Robinson and Brett Denevi of Johns Hopkins University’s Applied Physics Laboratory will be presenting the results from NASA’s Lunar Reconnaissance Orbiter mission today at the joint meeting of the European Planetary Science Congress and the American Astronomical Society’s Division for Planetary Sciences.

“Looking up at the Moon, its surface appears painted with shades of gray – at least to the human eye. But with the right instruments, the Moon can appear colorful,” said Robinson, a professor in ASU’s School of Earth and Space Exploration in the College of Liberal Arts and Sciences. “The maria appear reddish in some places and blue in others. Although subtle, these color variations tell us important things about the chemistry and evolution of the lunar surface. They indicate the titanium and iron abundance, as well as the maturity of a lunar soil.”

The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) is imaging the surface in seven different wavelengths at a resolution of between 100 and 400 meters per pixel (328 and 1312 feet per pixel). Specific minerals reflect or absorb strongly certain parts of the electromagnetic spectrum, so the wavelengths detected by LROC WAC help scientists better understand the chemical composition of the lunar surface.

Robinson and his team previously developed a technique using Hubble Space Telescope images to map titanium abundances around a small area centered on the Apollo 17 landing site. Samples around the site spanned a broad range of titanium levels. By comparing the Apollo data from the ground with the Hubble images, the team found that the titanium levels corresponded to the ratio of ultraviolet to visible light reflected by the lunar soils.

“Our challenge was to find out whether the technique would work across broad areas, or whether there was something special about the Apollo 17 area,” said Robinson.

Robinson’s team constructed a mosaic from around 4,000 LROC WAC images collected over one month. Using the technique they had developed with the Hubble imagery, they used the WAC ratio of the brightness in the ultraviolet to visible light to deduce titanium abundance, backed up by surface samples gathered by Apollo and Luna missions.

The highest titanium abundances in similar kinds of rocks on Earth are around one percent or less. The new map shows that in the mare, titanium abundances range from about one percent to a little more than ten percent. In the highlands, everywhere titanium is less than one percent. The new titanium values match those measured in the ground samples to about one percent.

“We still don’t really understand why we find much higher abundances of titanium on the Moon compared to similar types of rocks on Earth. What the lunar titanium-richness does tell us is something about the conditions inside the Moon shortly after it formed, knowledge that geochemists value for understanding the evolution of the Moon,” said Robinson.

Lunar titanium is mostly found in the mineral ilmenite, a compound containing iron, titanium and oxygen. Future miners living and working on the Moon could break down ilmenite to liberate these elements. In addition, Apollo data shows that titanium-rich minerals are more efficient at retaining particles from the solar wind, such as helium and hydrogen. These gases would also provide a vital resource for future human inhabitants of lunar colonies.

“The new map is a valuable tool for lunar exploration planning. Astronauts will want to visit places with both high scientific value and a high potential for resources that can be used to support exploration activities. Areas with high titanium provide both – a pathway to understanding the interior of the Moon and potential mining resources,” said Robinson.

The new maps also shed light on how space weather changes the lunar surface. Over time, the lunar surface materials are altered by the impact of charged particles from the solar wind and high-velocity micrometeorite impacts. Together these processes work to pulverize rock into a fine powder and alter the surface’s chemical composition and hence its color. Recently exposed rocks, such as the rays that are thrown out around impact craters, appear bluer and have higher reflectance than more mature soil. Over time this ‘young’ material darkens and reddens, disappearing into the background after about 500 million years.

“One of the exciting discoveries we’ve made is that the effects of weathering show up much more quickly in ultraviolet than in visible or infrared wavelengths. In the LROC ultraviolet mosaics, even craters that we thought were very young appear relatively mature. Only small, very recently formed craters show up as fresh regolith exposed on the surface,” said Denevi.

The mosaics have also given important clues to why lunar swirls – sinuous features associated with magnetic fields in the lunar crust – are highly reflective. The new data suggest that when a magnetic field is present, it deflects the charged solar wind, slowing the maturation process and resulting in the bright swirl. The rest of the Moon’s surface, which does not benefit from the protective shield of a magnetic field, is more rapidly weathered by the solar wind. This result may suggest that bombardment by charged particles may be more important than micrometeorites in weathering the Moon’s surface.

 

IMAGES
Figure 1: LROC WAC mosaic showing the boundary between Mare Serenitatis and Mare Tranquillitatis. The relative blue colour of the Tranquillitatis mare is due to higher abundances of the titanium bearing mineral ilmenite. Enhanced colour formed as 689 nm filter image in red, 415 nm in green, and 321 nm in blue [NASA/GSFC/Arizona State University].
http://www.europlanet-eu.org/outreach/images/stories/ep/news/epsc2011/lr...

Figure 2: Full resolution WAC three colour composite (566 nm filter image in red, 360 nm in green, and 321 nm in blue) highlighting region with varying mare compositions and enigmatic small volcanic structures known as “domes” [NASA/GSFC/Arizona State University].
http://www.europlanet-eu.org/outreach/images/stories/ep/news/epsc2011/lr...

Figure 3: LROC WAC Color Ratio 321 nm / 415 nm shows little variation due to crater rays. The dark haloed crater, Giordano Bruno, in the upper center is thought to be quite young and thus "immature" and thus still has a distinct UV signature. The most immature material on the Moon as defined by the UV maturity signal are the enigmatic "swirls". The swirls are likely due to local relatively intense magnetic fields standing off the solar swirl and thus protecting mineral grains from the maturing effects of solar wind sputtering [NASA/GSFC/Arizona State University].
http://www.europlanet-eu.org/outreach/images/stories/ep/news/epsc2011/lr...

Figure 4: LROC Wide Angle Camera mosaic centered on the lunar swirl Reiner Gamma and corresponding UV/visible light ratio (321/415 nm) [NASA/GSFC/Arizona State University].
http://www.europlanet-eu.org/outreach/images/stories/ep/news/epsc2011/lr...

 

(Anita Heward)

10/06/2011

WATCH THE VIDEO:

Sri Saripalli discusses field robotics innovations

Robots are becoming an essential and versatile tool for exploration under the sea, from the air and on other planets.

Arizona State University roboticist Sri Saripalli works on ways to advance technologies that will enable future robots to perform more complex tasks to aid astronauts and other explorers – especially in environments too harsh or dangerous for humans to venture.

In this video Saripalli describes a rover named RAVEN (Robotic Assist Vehicle for Extraterrestrial Navigation) developed by a group of ASU students as part of their senior-year “capstone” research and development project.

RAVEN took first place in the 2010 Revolutionary Aerospace Systems Concepts Academic Linkage (RASC-AL) – one of the premier astronautic design competitions for university-level engineering students – co-sponsored by the National Institute of Aerospace and the National Aeronautics and Space Administration.

The ASU students won over teams from 12 other major universities, including the Massachusetts Institute of Technology, Harvard, Georgia Tech, Virginia Tech, the University of Michigan and Rutgers University.

RAVEN is the type of technology engineers are developing to provide astronaut-scientists with robotic field assistants that could perform such tasks as scouting terrain and examining the geology of other planets.

The three-wheel, 330-pound rover can traverse 20-degree slopes and travel at speeds up to 3 feet per second. It has the ability to carry experimental gear, samples of materials, and tools.

The big challenge in the field, Saripalli explains, is to develop robots that could go beyond performing only simple tasks that they must be programmed to do. The goal is to get them to interact with astronauts and others on a basic level of intelligence.

That will require some complex advances in defining and developing “intelligent” technologies and devising a form of language that would enable humans and robots to communicate clearly and reliably.

Saripalli is an assistant professor in the School of Earth and Space Exploration (SESE) in ASU’s College of Liberal Arts and Sciences. SESE is also a collaborative partner of ASU’s Ira A. Fulton Schools of Engineering.

 

Caption: Professor Sri Saripalli coaches undergraduate student Sam Jacobs on how to use the controls for RAVEN rover at Camp SESE.

 

(Joe Kullman)

09/20/2011

Freshman year is an exciting time for Arizona State University students, but it can be overwhelming. ASU’s School of Earth and Space Exploration offered a special orientation program to help its newest members feel welcome and engaged in the mission of the school. Nearly 30 incoming freshmen and transfer students attended the three-day event over Labor Day weekend in the cool pines near Arizona’s Mogollon Rim.

During Camp SESE, the students learned about the exciting academic, extra-curricular, and research opportunities in the school. They hiked, navigated the rocky terrain with compasses and maps, drove robots, used telescopes to star-gaze, and engaged in team buildings exercises. All of which culminated in a unique bonding experience among the new students.

“Camp SESE recreates the sort of interactive environment and experience at the level of the School that have typically been the exclusive hallmark of small, elite liberal arts colleges – friendships and connections first established at this sort of camp can last a lifetime,” says Professor Kelin Whipple.

Whipple was instrumental in developing the concept for Camp SESE and doing much of the early heavy lifting to make it happen, but the camp was very much a community effort. Several SESE faculty and staff helped out, with the majority of the activities being overseen by upper-classmen mentors. Students connected with one another, but also with their upper division and graduate mentors, and with the faculty.

“It has been demonstrated that one key to college success is getting to know your professors outside the classroom,” says Kip Hodges, director of the School of Earth and Space Exploration. “Camp SESE is a wonderful opportunity for freshmen to spend time with volunteer faculty and staff members in a fun, informal atmosphere.”

“Having an opportunity like this for the freshmen and transfers is really a good way to get everyone to know each other,” says Christian Ferm, a freshman majoring in Earth and Space Exploration. “The collaboration between the undergraduate and graduate students was a really good idea.”

“We anticipate the annual Camp SESE event to play a key role in galvanizing a sense of community, a sense of family, within SESE,” says Whipple. The experience benefits everyone involved. “It is inspiring to see such an amazing group of incoming students – bright, motivated, inquisitive, and ready to explore in every sense of the word – and to get to know some of their diverse stories and perspectives.”


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09/06/2011

The Arizona State University team that oversees the imaging system on board NASA’s Lunar Reconnaissance Orbiter has released the sharpest images ever taken from space of the Apollo 12, 14 and 17 sites, more clearly showing the paths made when the astronauts explored these areas.

The higher resolution of these images is possible because of adjustments made to LRO’s elliptical orbit. On August 10 a special pair of stationkeeping maneuvers were performed in place of the standard maneuvers, lowering LRO from its usual altitude of 50 kilometers (about 31 miles) to an altitude that dipped as low as 21 kilometers (nearly 13 miles) as it passed over the Moon’s surface.

“The new low-altitude Narrow Angle Camera images sharpen our view of the Moon’s surface,” says Mark Robinson, the Principal Investigator for LROC and professor in the School of Earth and Space Exploration in ASU’s College of Liberal Arts and Sciences. The LROC imaging system consists of two Narrow Angle Cameras (NACs) to provide high-resolution images, and a Wide Angle Camera (WAC) to provide 100-meter resolution images in seven color bands over a 57-km swath.

“A great example is the sharpness of the rover tracks at the Apollo 17 site,” Robinson says. “In previous images the rover tracks were visible, but now they are sharp parallel lines on the surface!”

The maneuvers were carefully designed so that the lowest altitudes occurred over some of the Apollo landing sites.

At the Apollo 17 site, the tracks laid down by the lunar rover are clearly visible, along with distinct trails left in the Moon’s thin soil when the astronauts exited the lunar modules and explored on foot. In the Apollo 17 image, the foot trails—including the last path made on the Moon by humans—are more easily distinguished from the dual tracks left by the lunar rover, which remains parked east of the lander.

At each site, trails also run to the west of the landers, where the astronauts placed the Apollo Lunar Surface Experiments Package (ALSEP), providing the first insights into the Moon’s internal structure and first measurements of its surface pressure and the composition of its atmosphere.

One of the details that shows up is a bright L-shape in the Apollo 12 image marking the locations of cables running from ALSEP’s central station to two of its instruments. Though the cables are much too small to be resolved, they show up because the material they are made from reflects light very well and thus stand out against the dark lunar soil.

The spacecraft has remained in this orbit for 28 days, long enough for the Moon to completely rotate underneath, thus also allowing full coverage of the surface by LROC’s Wide Angle Camera. This low-orbit cycle ends today when the spacecraft will be returned to the 50-kilometer orbit.

These and other LROC images are available at: http://lroc.sese.asu.edu/

 

Apollo 12 image caption:

The tracks made in 1969 by astronauts Pete Conrad and Alan Bean, the third and fourth humans to walk on the Moon, can be seen in this LRO image of the Apollo 12 site. The location of the descent stage for Apollo 12’s lunar module, Intrepid, also can be seen.

Conrad and Bean performed two Moon walks on this flat lava plain in the Oceanus Procellarum region of the Moon. In the first walk, they collected samples and chose the location for the lunar monitoring equipment known as the Apollo Lunar Surface Experiments Package (ALSEP). The ALSEP sent scientific data about the Moon’s interior and surface environment back to Earth for more than seven years.

A surprising detail of the ALSEP is visible in the image: a bright L-shape marks the locations of cables running from ALSEP’s central station to two of its instruments. These instruments are probably (left) the Suprathermal Ion Detector Experiment, or SIDE, which studied positively charged particles near the Moon’s surface, and (right) the Lunar Surface Magnetometer, or LSM, which looked for variations in the Moon’s magnetic field over time; these two instruments had the longest cables running from the central station. Though the cables are much too small to be seen directly, they show up because the material they are made from reflects light very well.

In the second Moon walk, Conrad and Bean set out from the descent stage and looped around Head crater, visiting Bench crater and Sharp crater, then headed east and north to the landing site of Surveyor 3. There, the astronauts collected some hardware from the unmanned Surveyor spacecraft, which had landed two years earlier.

The two astronauts covered this entire area on foot, carrying all of their tools and equipment and more than 32 kilograms (roughly 60 pounds) of lunar samples.

 

Apollo 14 image caption:

The paths left by astronauts Alan Shepard and Edgar Mitchell on both Apollo 14 Moon walks are visible in this LRO image. (At the end of the second Moon walk, Shepard famously hit two golf balls.) The descent stage of the lunar module Antares, measuring about 5 meters across, is also visible.

Apollo 14 landed near Fra Mauro crater in February 1971. On the first Moon walk, the astronauts set up the lunar monitoring equipment known as the Apollo Lunar Surface Experiments Package (ALSEP) to the west of the landing site and collected just over 42 kilograms (about 92 pounds) of lunar samples. Luckily for them, they had a rickshaw-style cart called the modular equipment transporter, or MET, that they could use to carry equipment and samples.

 

 

 

Apollo 17 image caption:

The twists and turns of the last tracks left by humans on the Moon crisscross the surface in this LRO image of the Apollo 17 site. In the thin lunar soil, the trails made by astronauts on foot can be easily distinguished from the dual tracks left by the lunar roving vehicle, or LRV. Also seen in this image are the descent stage of the Challenger lunar module and the LRV, parked to the east.

The LRV gave the Apollo 17 astronauts, Eugene Cernan and Harrison Schmitt, considerable mobility. As in previous Apollo missions, the astronauts set up the lunar monitoring equipment known as the Apollo Lunar Surface Experiments Package (ALSEP), the details of which varied from mission to mission. To the west of the landing site, the cross-shaped path that the astronauts made as they set up the geophones to monitor seismic activity can be seen.

To the east, more rover tracks can be seen. Cernan made these when he laid out the 35-meter antennas for the Surface Electrical Properties, or SEP, experiment. SEP, a separate investigation from ALSEP, characterized the electrical properties of the lunar soil.

Below the SEP experiment is where the astronauts parked the rover, in a prime spot to shoot video of the liftoff of the Challenger module.

Link to Apollo 17 liftoff video: http://history.nasa.gov/alsj/a17/a17v_1880127.mpg

 

(Nikki Cassis)