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Home » Meteorites » Hunting Meteorites in Antarctica


Hunting Meteorites in Antarctica


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Incredible numbers of nearly perfect meteorites are being found in the "blue ice" ablation areas of Antarctica. The photo above shows several specimens collected from the Miller Range icefield by NASA's The Antarctic Search for Meteorites. Image by NASA.


The Best Place to Hunt Meteorites



In most parts of the world a person could search throughout a lifetime and never find a single meteorite. However, researchers are finding several hundred meteorites every year in a few special locations in Antarctica.

In most parts of the world meteorites are very difficult to find because meteorites that fall there can be...
  • quickly destroyed by weathering
  • hard to distinguish from local materials
  • hidden by vegetation
  • covered by surface materials

Advantages of Cold Climate



In Antarctica, freshly-fallen meteorites are protected by the cold climate. Iron meteorites do not rust in the cold conditions and stony meteorites weather slowly.

Meteorites are also very easy to see against the white snow/ice background. Searchers can walk or snowmobile across the ice and visually locate meteorites that might only be a centimeter across. This is why hundreds are found every season.

Although the cold climate is great for preserving meteorites it presents a huge challenge to the researchers who hunt them. They have to travel to a remote location where they will live in tents in subzero weather. When out on the hunt they face face subzero temperatures, fierce wind and blistering sun. It takes a determined and dedicated person to do this for several weeks each year.


Ice Movement and Meteorite Concentration



The two most important reasons why meteorite hunting in some parts of Antarctica is so productive are ice movements and ablation.

The ice of the Antarctic continent is in motion. The ice grows thicker in some areas from snow accumulation, then it slowly flows away from those areas under its own weight. Remember that the continent is covered by a glacier.

The theory of ice movement is shown in the diagram below. It shows how meteorites are buried in zones of snow accumulation. Then the ice moves under its own weight away from these snowfields towards the edge of the Antarctic continent. In some areas rock formations block the flow of ice. Where this occurs steady Katabatic winds can remove the ice by sublimation and mechanical abrasion. Up to ten centimeters of ice per year can be removed by these ablation processes.


How Antarctic ice transports meteorites
When meteorite hunters find a specimen in the field it is photographed in-place with a measurement scale and an identification number visible in the background. NASA image.


Curating Pristine Meteorites



The meteorites found in Antarctica are in pristine condition. They are not weathered like meteorites found in temperate climates. The original fusion crust formed by ablation of the meteorite as it fell through the atmosphere is often preserved.

When researchers find a meteorite it is numbered and photographed before it is removed from the ice. It is then carefully removed from the ice, placed in a clean container to avoid contamination and kept at cold temperatures until adhering snow and ice can be removed by sublimation.


Stone Meteorites from Moon and Mars



Almost all of the meteorites found on Earth are believed to be pieces of asteroids. Some researchers believe that five to six percent are pieces of the asteroid Vesta. They are pieces of Vesta that were dislodged by impacts with other asteroids.

A very small number (less than two hundred) meteorites have been determined to be pieces of Moon or Mars after careful study. They arrived on Earth after being dislodged by asteroid impacts and travelled through space for millennia before falling to Earth.

A few of these rare meteorites have been recovered from Antarctica. The lunar meteorites are rocks such as anorthositic breccia, basaltic breccia, gabbro and mare basalt. An orthopyroxenite rock from Mars has also been found.


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meteorite find
When meteorite hunters find a specimen in the field it is photographed in-place with a measurement scale and an identification number visible in the background. NASA image.




map of meteorite hunting areas in Antarctica
When meteorite hunters find a specimen in the field it is photographed in-place with a measurement scale and an identification number visible in the background. NASA image.


meteorite hunting weather
This photograph shows what conditions can be like for meteorite hunters in Antarctica. NASA image.


Antarctic Meteorite Information
[1] Searching Antarctic Ice for Meteorites: an article about the ANSMET Program (Antarctic Search for Meteorites) on the NASA website, February, 2011.

[2] Antarctic Meteorite Program: an article about the US Antarctic Meteorite Program on the NASA website, May 31, 2011.

[3] Antarctic Meteorite Recovery Locations: map showing the location of meteorite recovery sites in the Transantarctic Mountains of East Antarctica, posted on the NASA website, accessed March, 2013.

[4] Antarctic Meteorite Newsletter: an index to copies of the Newsletter from August 1994 through present. The newsletter contains classification information, petrographic descriptions, photographs and other information about meteorites recovered during each field season.


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