Scientists believe that they have discovered the Earth's oldest known rock, but what makes this rock truly unique, besides its age, is that it was first found on the moon decades ago in 1971 by Apollo 14 astronauts and then taken back to Earth.
As National Geographic reports, this unique and ancient rock was once part of the deep regions of the Earth, residing approximately 12.4 miles below our planet's crust, and has been estimated to date back over at least 4.011 billion years.
While scientists note that it is certainly possible that the rock was created in a region of the moon which contained plenty of magma and water, they believe that the odds are much higher that the ancient rock was created here on Earth and was eventually swept away to the moon, perhaps at the time of a catastrophic meteor impact with the Earth.
According to the Nation, up until now, the oldest known rocks on Earth were found to be around two billion years of age, and with its vast age, this over four-billion-year-old rock would have been created at around the same time as the Earth was also being forged.
If the rock that the crew of Apollo 14 discovered is truly of this Earth, this would make it the first time that something like this has ever happened, as Cornelia Rasmussen, of the University of Texas at Austin, noted.
"If that's true, then this is quite a fascinating finding. We don't really have a rock record of this time on Earth, which means the find gives us a window to a time we can't really study here."The credit for the discovery of this rock goes to Apollo 14 astronaut Alan Shepard, who first picked up the ancient object on February 6, 1971. The rock, which was first categorized under the name 14321, also happens to be one of the biggest that any Apollo mission retrieved from the moon and brought back to Earth.
David Kring, lead author of the new study on the rock and CLSE principal investigator, has stated that the discovery demonstrates how volatile early life was on Earth with so many meteor impacts, noting, "It is an extraordinary find that helps paint a better picture of early Earth and the bombardment that modified our planet during the dawn of life."
The fascinating new study which describes the over four-billion-year-old Earth rock that was found on the moon has been published in Earth and Planetary Science Letters.