Jan 24, 2012

Hundreds of Meteorites Uncovered in Antarctica

A gang of heavily insulated scientists has wrapped up its Antarctic expedition, with its members thawing out from the experience, but pleased to have bagged more than 300 space rocks.

They are participants in the Antarctic Search for Meteorites program, or ANSMET for short. Since 1976, ANSMET researchers have been recovering thousands of meteorite specimens from the East Antarctic ice sheet. ANSMET is funded by the Office of Polar Programs of the National Science Foundation.

According to the ANSMET website, the specimens are currently the only reliable, continuous source of new, nonmicroscopic extraterrestrial material. Given that there are no active planetary sample-return missions coming or going at the moment, the retrieval of meteorites is the cheapest and only guaranteed way to recover new things from worlds beyond the Earth.

Special place

"It has been another interesting season at Miller Range," said Ralph Harvey, associate professor in the department of Earth, Environmental and Planetary Sciences at Case Western Reserve University in Cleveland, Ohio.

"The place is special for us because we seem to find meteorites everywhere, in every little nook and cranny, almost unpredictable," Harvey told SPACE.com. "And it did it again ... lots of places we checked out just to be complete proved to have dozens of specimens."

Harvey is the principal investigator for the ANSMET program. "I've been leading field parties since 1991 and I think this year marks my 25th overall with the program," Harvey said.

Harvey likens his search for meteorites to a farmer who's used to harvesting corn in a field finding it growing in the barn, in the garage, in the basement and other surprising spots.

The meteorite hunting wasn't all smooth, though.

The team was held back significantly by early snowfalls that buried the meteorites. Even though a few strong windstorms cleared some of it, the whipping winds did not clear all of it, Harvey explained.

"The total number of meteorites is less than half what I would have predicted, again primarily because of that early snow hiding all the specimens," Harvey said. "We'll be going back to the Miller Range at least one more time and maybe two."

Celestial collectibles

Antarctica is viewed as the world's premier meteorite hunting ground, and for good reason.

While meteorites fall in a random fashion all over the globe, the East Antarctic ice sheet is a "desert of ice," a stark scene that enhances the likelihood of finding meteorites, which are usually undisturbed and stand out against the background.

In the just-concluded search, the team's bounty of celestial collectibles brought the total number of meteorites found in ANSMET history to 20,000.

Along with Harvey, the meteorite hunters are:

John Schutt, an ANSMET mountaineer for over 30 years who once again played that role. He recently got an honorary doctorate recognizing his contributions to planetary science.

Jim Karner, a postdoctoral researcher working with the ANSMET program and a specialist in Martian meteorites from Case Western Reserve. He's a veteran of four ANSMET expeditions.

Christian Schrader, a geologist from NASA Marshall Space Flight Center in Huntsville, Ala., who has done significant rock work, particularly in studying lunar meteorites.

Katie Joy, planetary geologist, most recently from the Lunar and Planetary Institute in Houston, Tex., and a lunar meteorite researcher.

Anne Peslier, a planetary scientist from NASA's Johnson Space Center in Houston who has done a great deal of work on Martian meteorites.

Jake Maule, a planetary scientist, recently of Carnegie Institute in Washington, D.C., with a specialty in astrobiology.

Jesper Holst, a Ph.D. student studying planetary geochemistry at the University of Copenhagen.

Tim Swindle, a planetary geochemist from the University of Arizona, taking part in the second half of the season, and a veteran of several previous expeditions.

Read more at Discovery News

No comments:

Post a Comment