Antarctic search for meteorites program at CWRU expands with

by Susan Griffith of Case Western Reserve University

CLEVELAND--As the Antarctic Search for Meteorites program (ANSMET) of Case Western Reserve University begins its 26th annual trip onto the ice fields of Antarctica, new support from the National Aeronautics and Space Administration (NASA) has allowed ANSMET to create a new reconnaissance team to augment the existing National Science Foundation (NSF) supported team.

These teams will search the blustery, frozen landscape for pieces of Mars and other solar system bodies during six weeks of exploration.

Support for CWRU's new ANSMET team and its 2002 field season came from a three-year, $1.6 million grant from NASA. "NASA's support of the ANSMET program allows this valuable planetary science program to grow in new and promising ways," says Ralph Harvey, CWRU planetary geologist and ANSMET director.

The new ANSMET team will travel light and be well-supported by small aircraft, allowing them to explore many poorly known and hard-to-reach sites in a single season while also recovering significant numbers of new meteorites.

This year, the reconnaissance team will explore ice fields in the region around the Pecora Escarpment, roughly 200 kilometers from the U. S. Amundsen-Scott South Pole Station.

The larger NSF-supported team will focus on systematic recovery of meteorite specimens from ice fields where high concentrations have been previously discovered.

This year they will search near the Goodwin Nunataks and MacAlpine Hills, near the head of the Beardmore Glacier in East Antarctica.

The prospect that enables the expedition scientists to brave Antarctica's cold and windy conditions is the potential of collecting specimens that originated from Mars or other exotic solar system bodies, explains Harvey.

Of the more than 11,800 meteorites recovered by ANSMET over the past quarter century, about 5 percent are unusual enough to be of high scientific interest, and about one out of 1,000 is from the moon or Mars.

The five Martian meteorites found by ANSMET have been central to NASA's advancing efforts to explore Mars, says Harvey.

ALH77005, found in the Allan Hills region by ANSMET in 1977, was the first Martian meteorite found in Antarctica and the seventh specimen known worldwide. It generated enormous scientific interest and brought this enigmatic group of specimens into the forefront of planetary research. EETA79001, recovered two years later at the Elephant Moraine ice field, provided the dramatic conclusive link between these meteorites and Mars. LEW88516 was found in 1988 at the Lewis Cliff Ice Tongue and has been the focus of many studies including research on the abundance of water on Mars. ALH84001, found by ANSMET in 1984 near the Allan Hills, is perhaps the most famous of all the Martian meteorites, and the focus of intense debate concerning possible signs of ancient microbial life on Mars. The last Martian meteorite found by ANSMET was QUE94201, a uniquely young but primitive volcanic rock found in the Queen Alexandra Range in 1994.

Curated by the Johnson Space Center and Smithsonian Institution, ANSMET samples are available to researchers around the world for planetary geology research.

"As NASA prepares to embark upon a decade of intensified in situ exploration of Mars and on the way to an era in which sample return will be a key facet of our program, the collection of priceless meteorite samples from Antarctica is a vital step," says James Garvin, NASA lead scientist for Mars Exploration. "By supporting a dual-sampling team approach this year, NASA hopes to return a diversified set of meteorite samples and to increase the possibility of discovering additional meteorites from Mars," adds Garvin.

Participating in ANSMET's meteorite recovery efforts this year are Carlton Allen, Dean Eppler and Catherine Coleman from NASA's Johnson Space Center; Andy Caldwell, a high school teacher from Douglas County High School in Castle Rock, Colo.; Daniel Glavin, Max-Planck Institute for Chemistry in Mainz, Germany; Diane DiMassa, University of Massachusetts at Dartmouth; Dante Lauretta, University of Arizona; Scott Messenger, Washington University in St. Louis; and Linda Welzenbach, Smithsonian Institution. Nancy Chabot of CWRU's department of geological sciences is a veteran of two previous ANSMET expeditions and will be the lead scientist for this year's fieldwork, while James Pierce of Colorado and John Schutt of Washington State will be the expedition mountaineers.

For information, contact Ralph Harvey at 216-368-0198 or by e-mail at rph@po.cwru.edu. Further information on ANSMET activities, including maps, images and daily updates from the field can be found at the ANSMET Web site at http://www.cwru.edu/affil/ansmet.

The ANSMET Web site also includes links to associated sites such as Antarctic meteorite facilities at NASA's Johnson Space Center.