Could the secrets of the solar system’s formation be buried beneath the Antarctic ice sheet? A team of researchers from the University of Manchester believe the answer is yes, and that those secrets are contained in a layer of iron-rich meteorites just centimeters from the surface.
More than two-thirds of the meteorites collected by scientists come from Earth’s southernmost landmass, but according to BBC News, precious few of those space rocks are made of iron. In their new study, Dr. Geoff Evatt, Dr. Katherine Joy and their colleagues used a series of models and laboratory experiments to determine if those metallic meteorites might be buried.
As the Manchester researchers explained in a recently-published Nature Communications paper, they believe that the meteorites have been difficult to find because of the way in which the sun’s rays penetrate clear ice in the regions of the ice sheet called Meteorite Stranding Zones or MSZs. This warms the iron-rich meteorites more than the non-metallic space rocks, melting the ice that surrounds these meteorites. As a result, they sink and become permanently trapped.
Dr. Evatt, Dr. Joy and their co-authors used several experiments and mathematical simulations which indicate that ordinary thawing and freezing processes would negate the upward movement of meteorites with high thermal conductivity, such as those containing iron. This results in rocks with lower conductivities (those with low iron content) to emerge from the ice.
Metallic meteorites could shed new light on the early solar system
If their projections are accurate, this means that layers of ice less than 100 centimeters beneath the surface of an MSZ could contain an abundant amount of iron-rich meteorites that have been preserved for several thousands of years. Recovering these space rocks could drastically improve our understanding of the early solar system, from which they likely originated.
“The idea is, they never make it to the surface. They’re forever trapped, 50-100cm or so below the ice,” Dr Joy told BBC News. “When it’s very cold… picking up the sample in a controlled way is difficult enough with things sitting on the surface. To access ones that are subsurface – nobody’s really tried to do that so far.”
“With the strong possibility that a hidden reserve of meteorites lies just below the ice surface of localized areas of Antarctica, finding conclusive evidence of its existence is imperative to our understanding of the Solar System’s formation,” Dr. Evatt added in a statement. “The challenge is now set: to be the first team to locate this reserve of meteorites and retrieve samples from it.”
While it will not be easy to attempt to recover these meteorites from beneath the ice, the study authors are hopeful that radar equipment and metal detectors might help them determine which places will be the best excavation targets. And, as Dr. Joy told the BBC, the potential benefits of such efforts could be tremendous, as “every meteorite we find tells us something new about the Solar System.”
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Feature Image: Meteorite lodged in Antarctic ice. (Credit: The University of Manchester)
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