Wednesday, January 18, 2012

Meteorites that fell to Earth during a meteor shower in July of 2011 have been confirmed to be from Mars. The rocks, discovered in Morocco, were likely ejected off the surface of the planet during an ancient asteroid impact.

This is believed to be the fifth time in history that people have observed what turned out to be chemically confirmed martian material falling to Earth. Out of the approximately 24,000 known meteorites to have fallen to Earth, only about 34 have been verified to be martian in origin. Fifteen of these rocks are attributed to the meteorite shower last July. Some of the rocks, which are very rare on Earth, are being sold from US$11,000 to $22,500 per ounce, which is about ten times more than the cost of gold.

Meteorites confirmed to be from Mars fell to Earth in 1815, 1865, 1911 and 1962. The sooner the rocks are recovered after landing on Earth, the less they are contaminated by its natural processes. This allows scientists to examine specimens and gain insight about the geology of Mars. “Because it’s so fresh, if you find organics in this sample, you can be pretty sure those organics are Martian,” Carl Agee, director of the Institute of Meteoritics at the University of New Mexico, told Space.com.

Scientists postulate that a large object’s impact into Mars millions of years ago was the cause of the material’s ejection from the surface of the planet.