A bed of iron meteorites that may hold clues to how the solar system was formed may be hidden under the Antarctic ice sheet, a new study found.
The meteorites may be just within reach, with the authors saying that it could be just 10 to 50 centimeters (3.9 to 19.7 inches) from the surface. How cool is that?
The Mystery Of Iron Meteorite Stores In Antarctica
Meteorites from space are located evenly across the surface of the Earth. However, Antarctica appears to be one of the best playgrounds for meteorite researchers. This is because more than two-thirds of unearthed meteorites have been found here.
While the contrast of colors between the white Antarctic ice and the dark meteorites may contribute to easier searches, the main reason is the dynamics of ice flow in the region.
The ice movement is what takes and concentrates meteorites that have been buried hundreds of years ago. This enables meteorites to move up into the localized areas at the surface called Meteorite Standing Zones (MSZs). Such process explains why scientists are enjoying fruitful quests in the region since the 1970s.
Despite such abundance, scientists are baffled as to why there is a significant scarcity of iron-rich meteorites in Antarctica. In fact, the amount of these meteorites found here are far fewer than anywhere else in the entire world.
Mystery Solved
The researchers of the new study may have solved the mystery. They suggest that the meteorites are absent because the sun's rays are piercing through the clear ice in the MSZs. This melts iron-rich meteorites faster than non-metallic ones.
The high temperature of the melting meteorites is passed onto the surrounding ice, which subsequently submerge the rocks far down. The heat topples down the ice swelling that transpired all year long, resulting in the rocks to be trapped even further beneath the ice sheet surface.
To come up with their findings, the researchers used a combination of laboratory and mathematical techniques to demonstrate how common thawing and freezing can block the upward movement of the iron-rich meteorites with high thermal conductivity. Conversely, those with lower conductivity become more apparent on the ice surface.
Size also contributes to the fate of the meteorites. Large rocks emerge on the surface more than the small ones because the latter has an increased ability to transmit heat to the surrounding ice for melting.
"This is an important caveat to make, for the high number of freeze/thaw cycles an iron meteorite can be expected to go through may explain why smaller masses of iron meteorites are recovered from Antarctica as compared with the rest of the world," the authors write.
More Info About The Solar System
Iron-rich meteorites are said to have come from large planetary bodies that broke apart. Being able to access this layer filled with iron-rich rocks may pave the way for scientists to learn more about the origins of the Solar System.
The quest for this layer is exciting as it may contain more than just additional information about the Solar System, it may actually hold conclusive evidences.
"The challenge is now set: to be the first team to locate this reserve of meteorites and retrieve samples from it," says Geoffrey Evatt, who is part of the team from the University of Manchester.
The study was published in the journal Nature Communication on Tuesday.
Photo: Juan Manuel Fluxà | Flickr
