More than 50,000 years ago, a meteor hit Earth and formed what we now call Meteor Crater in northern Arizona. But new ...

Early in the morning of October 6, 2008, astronomers at the University of Arizona detected an asteroid on a collision course with Earth. When other sightings cropped up across the world, the ...

View from the Grand Canyon's South Rim onto Nankoweap Delta. Remnants of a past natural dam created by a landslide are visible on the far side of the Colorado River, just to the left of the dry bed of ...

A recent study from the University of New Mexico has proposed a fascinating theory about the formation of the Grand Canyon. The research suggests that the Meteor Crater impact, which occurred ...