Tales from the vault: ASU's meteorite collection holds mysteries
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.
Gift from abroad
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.”
Written by Victoria Miluch
Nicole Cassis, email@example.com
School of Earth and Space Exploration