Chile's Atacama Desert, which gets less than 5 millimeters (0.2 inches) of rainfall each year, started to form more than 40 million years ago ‪—‬ 20 million years before the Andes.

A man went to hospital complaining about weakness in his left leg, and subsequent brain scans revealed his abnormally small brain.

The silver in a Viking Age hoard found in Denmark was from melted-down coins from the faraway Islamic world, a new study finds.

Researchers have filmed goblin sharks in the deep sea for the first time. Until now, these sharks had been seen alive only after being hauled up to the surface with fishing lines.

China is building a dam system that will generate more hydroelectric power than the U.S. generates yearly. But the project comes with huge risks for people downstream.

Antarctica was long thought to be seismically calm, but new technology makes it possible to detect unexpected types of earthquakes beneath the ice.

A meteorite shows evidence that an ancient crash on the moon 3.5 billion years ago was so powerful, it turned the surface molten.

This skull-shaped mask was made to be used in a ritual involving the Aztec god of death.