Scientists have proposed a shocking new theory for the origin of the moon, and their calculations suggest Earth once had a secret world hiding right next door. Astronomers believe that the moon was ...

The last total lunar eclipse visible from the U.S. happened less than a year ago, on March 13, 2025. That night, it was cloudy in Duluth, but satellite photos showed clear skies about 75 miles to the ...

About 4.5 billion years ago, the most momentous event in the history of Earth occurred: a huge celestial body called Theia collided with the young Earth. How the collision unfolded and what exactly ...