A microbial geneticist at the University of Maryland has proposed that early life may have tinged the Earth purple.
Astronomers are learning more about the brightening and dimming of stars.
Learn about gravity, stars, and really big lumps.
Why is there life on Earth? Water, a rocky surface, the right amount of distance, and ____________.
Is the force of gravity increasing? Find out on this Moment of Science.
Trilobites and 95 percent of marine creatures went the "way of the dinosaurs" during the Permian extinction, millions of years before dinosaurs existed.
Geologists posit that Earth was once entirely covered by ice.
Data from the Rosetta mission, the Mars rover and the Herschel space observatory point to water's extraterrestrial origins.
*Beware of alarmist headlines. The odds are slim when it comes to giant Earth-bound asteroids.
Most of us take our oxygen-rich atmosphere for granted. Once upon a time, though, Earth's air was very different.