In addition to Disneyland, my daughter is now asking for a trip to Antarctica. It’s not that she loves the cold or needs to see some penguins, but because it’s a great place to collect rocks… that fell from space. While the entire planet is estimated to be littered with tens of thousands of meteorites per year, they’re usually landing in places that make them very hard to recover, like the oceans. Antarctica then provides a special opportunity, as there is little to obscure your view of a dark meteorite nestled in the white snow and ice. It’s not a total cake walk though, as scientists have noticed that a portion of the expected meteorites in Antarctica seem to be missing.
Iron in the ice
Based on surveys of other barren areas of Earth, like sandy deserts, researchers have estimates for the amount of space rocks they’d expect per square mile of land per year. Antarctica has it’s share of many of these rocks, suggesting that the southernmost continent is not being picked over by the collectors my daughter wants to join. However, the iron-based meteorites don’t turn up in the expected quantities, and researchers are planning to scour the South Pole to see where they’ve all gone.
The current hypothesis is that the 4.8 percent of meteorites that can’t be accounted for have somehow submerged themselves deeper into the Antarctic ice. It may be as straightforward as the dark iron metal collecting heat in the sun, and melting a hole in the snow and ice before being buried. The hope is to clear this up with metal detectors, because if these meteorites aren’t there, there’s a much bigger mystery to solve about why the distribution of falling meteors would be uneven around the South Pole.
Pieces of planets
If the missing meteorites are simply sitting under a layer of ice, there’s still a lot to learn from them. The iron in a meteorite is usually very old, possibly dating back to the formation of our solar system. As proto-planets congealed and collided, pieces of rock and iron would have broken off to float through space, at least until they collided with something bigger like the Earth. If these meteorites can be recovered, the hope is that they can be used like a time capsule to see what the chemistry of our solar system once looked like.
My third grader asked: If I did find a meteorite, could I keep it?
That depends. In the United States, if you find a rock from space on private property, it’s that property-owner’s rock, so you have to negotiate with them. If the meteorite turns up on public land, they technically belong to the federal government. You might then need permits specific to your intended use of the meteorite, although how that’s enforced apparently depends a lot on how the local Bureau of Land Management operates.
As for meteorites in Antarctica, things operate differently since technically no government runs that continent. The Antarctic Treaty from 1959 does allow the collection of specimens for scientific study, and nobody is allowed to sell them. This is apparently a great way for research institutions to get access to meteorites without worrying about breaking their acquisitions budget.
Source: The quest to solve the mystery of Antarctica's 'lost meteorites' by Bryan Nelson, Mother Nature Network