Oldest Piece of Earth Discovered

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Scientist have discovered a ancient crystal called a zircon to about 4.4 billion years, making it, the earliest confirmed piece of the planet’s crust according to CNN.

The zircon was extracted in 2001 from a rock outcrop in Australia’s Jack Hills region. The rock was Screen Shot 2014-11-24 at 8.00.52 PMwww.coloradonewsday.com
rather small and it is only about 200 by 400 microns, about twice the diameter of a human hair, reported independent.co.uk.com

“This confirms our view of how the Earth cooled and became habitable,” said study leader John Valley of the University of Wisconsin-Madison, to news.nationalgeographic.com  in a statement. “This may also help us understand how other habitable planets would form.”

Zircons are tough pieces of rock that have been clumped together and solidified into new material, which means that they still harbor clues about the conditions which they were formed stated pbs.org. This tells us that the earth had cooled down enough by its 100-millionth birthday that it was able to form a rocky crust and the temperature could have been low enough to sustain life.