About 3.8 billion years ago, two massive canyons likely formed on the moon in a span of less than 10 minutes, according to new research. The extraordinary formations, each comparable in size to ...

A giant impact 3.8 billion years ago sent a curtain of rock flying away from a point near the moon’s south pole. When that curtain fell, its rocks plunged up to 3.5 kilometers into the lunar surface ...

Hike through secret slot canyons, spot endangered California condors, visit sacred Navajo sites, and kayak a stunning 10-mile ...

The Canyon's Age Sparks Fierce Scientific Debate Scientists have spent over a century arguing about when the Colorado River first carved through the Colorado Plateau. A diverse set of geologic studies ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. About 3.8 billion ...