The team—which consists of geochemists Maria Schönbächler, Vinciane Debaille, and Ryoga Maeda as well as cosmochemist Maria Valdes—began their Antarctic expedition in December. When they returned in mid-January, it was with five meteorites, including one that weighs a whopping 16.7 pounds.
Despite it being summertime in Antarctica, temperatures sat around 14 degrees Fahrenheit (-10 degrees Celsius) throughout the expedition. But for those who are willing to brave such a climate in a remote environment, Antarctica makes for a perfect meteorite hunting site. Low precipitation means space artifacts face less erosion from water; in a sense, they’re preserved by the icy desert. Finding the meteorites is easier, too, since their dark surfaces contract with the bright, snowy ground.
NASA estimates that about 45,000 meteorites have been located in Antarctica over the past 111 years, while up to 300,000 more still wait in the ice. Very few are as physically impressive as this team’s discovery; the average stony meteorite is between just 4.5 and 9 ounces (128 and 256 grams). Only about 100 of the meteorites found in Antarctica can compare.
Two researchers collecting a meteorite in Antarctica’s Miller Range in 2013. (Image: NASA/JSC/ANSMET)
“Size doesn’t necessarily matter when it comes to meteorites, and even tiny micrometeorites can be incredibly scientifically valuable,” Valdes told Chicago’s Field Museum, which supported her portion of the expedition. “But of course, finding a big meteorite like this one is rare, and really exciting.”
To locate each of their finds, the team walked and rode snowmobiles through portions of Antarctica that satellite imagery had previously helped to identify as meteorite landing spots. They tested potential meteorites’ magnetic properties before pulling the rocks from the ice. Once the researchers got home, they divided a collection of sediment among themselves with the goal of independently finding micrometeorites—AKA cosmic dust—among the sand. They’ve sent their five meteorites to the Royal Belgian Institute of Natural Sciences for analysis.
Studying these meteorites—and any others found in forthcoming expeditions—will offer key insights about the universe at large, including how planets form and how certain asteroid fragments become meteorites.
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