By 1990, Earth Day went global as 200 million people in 141 countries celebrated by calling attention to various environmental issues. Today, Earth Day is one of the largest secular observances in ...

Mercury, Venus, Mars, Jupiter, Saturn, Neptune and Uranus could be visible, but not all can be seen by the naked eye.

Firefly will be livestreaming the landing attempt on its YouTube page. The livestream will start at 2:20 a.m. ET on Sunday, ...

The asteroid is hurtling towards us at a zippy 15,000 miles per hour, according to the space agency's Jet Propulsion ...

The lander, Blue Ghost, fired its engines for four minutes Thursday to propel the spacecraft into lunar orbit ahead of a ...