What on Earth?

Six breathtaking images, six unfathomable mysteries, from a gigantic tsunami that never hits land to a secret underground base in China. Plus, an image from space may have finally revealed the location of the Garden of Eden.

Six more mysteries captured from space are investigated, including weird, barren rings in the Namib desert, a vanishing island and a lost city in the heart of the Amazon jungle.

Experts are baffled by a beautiful yet mysterious formation in the Sahara desert, and extraordinary clouds emanating from the Indian Ocean may be evidence of a terrifying new weather weapon.

An astronaut photographs a strange ring of ice on the world's oldest and most mysterious lake.

A possible smokescreen over North Korea worries military analysts, while an amateur archaeologist makes an extraordinary discovery with the help of a satellite image

Images of Earth from space reveal an intimate portrait of human activity. Cities glow bright while the wilderness remains dark. Why then is the Australian outback lit up like a series of vast cities?