In the vast skies above the Grand Canyon, astronomer David Koerner found the formula for awe. Here's how.

They were looking at deep time. The rocks in the Grand Canyon span from 270 million to 1.8 billion years old, a stunning backdrop against which human existence is but a mere blip. Just before the ...

Courtesy Grand Canyon Scenic Airlines The first thing some people do when visiting Las Vegas is immediately leave it—and go ...

Two Grand Canyon-size features on the far side of the moon were likely formed in about 10 minutes after an unknown object slammed into the moon 3.8 billion years ago.

They were looking at deep time. The rocks in the Grand Canyon span from 270 million to 1.8 billion years old, a stunning backdrop against which human existence is but a mere blip. Just before the ...

At least 16 people have died at the park this year, including five fatalities in August alone. No single factor is to blame, but several deaths have followed stretches of extreme weather.

More than 99% of Americans live under skies polluted by light. But dark skies at the Grand Canyon and more than 145 other spots offer stargazing awe.

The Grand Canyon Is One of Our Most Beloved National Parks. These Reviewers Beg to Differ. “Seen better”: Not every visitor is impressed with one of the world’s seven natural wonders, it ...

The Grand Canyon is the biggest canyon on earth: 277 miles long, 10 miles wide, and a mile deep. It contains some of the oldest exposed rock on earth, Precambrian Vishnu schist, formed 1.7 billion ...

They were looking at deep time. The rocks in the Grand Canyon span from 270 million to 1.8 billion years old, a stunning backdrop against which human existence is but a mere blip.

They were looking at deep time. The rocks in the Grand Canyon span from 270 million to 1.8 billion years old, a stunning backdrop against which human existence is but a mere blip. Just before the sun ...