WASHINGTON—The Grand Canyon in Arizona is one of Earth’s natural wonders, carved out over millions of years by the gradual erosion power of the Colorado River. Close to the moon’s south pole are two canyons each comparable in size to the Grand Canyon that were born in a much different process.
New research indicates that these canyons, in an area called the Schrödinger impact basin on the side of the moon perpetually facing away from Earth, were dug out in a matter of less than 10 minutes by rocky debris sent violently aloft when an asteroid or comet struck the lunar surface roughly 3.8 billion years ago....
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