What on Earth?

Strange spots near the Grand Canyon may hold clues to a legendary treasure, satellite images could explain desert ruins rumored to be an entrance to the underworld and a city-sized chunk of ice suddenly disappears in Antarctica.

A giant carving of a strange creature suddenly appears in the Australian outback, mysterious lights illuminate the seas around Thailand and top-secret activity is discovered at Iran's nuclear facility.

Strange black holes appear near Egypt's ancient pyramids, ruins in Peru suggest the Inca knew far more than previously thought and a mysterious swarm invades a beach in India.

Legends of ancient giants surround a mysterious monument in the Holy Land, a bright pink lake could point to a strange, undiscovered new species and satellite images help locate a young boy lost in a sand dune.

Investigators find a new clue about the missing Malaysia Airlines flight that disappeared in 2014, an astronaut spots something strange in the Sahara desert and a mysterious orange sludge invades a remote village in Alaska.

A buried monument offers new evidence about one of the Bible's greatest mysteries, an ominous shadow engulfs the Pacific Ocean and scientists have trouble explaining a strange lake shaped like a perfect circle.

A dagger from King Tut's tomb may have extraterrestrial origins, a massive swastika is found near Roswell, New Mexico, and satellites hunt for the world's most-wanted man.

Heavily armed forces take over one of Syria's most ancient archaeology sites, tanks appear to be facing off in Antarctica next to an otherworldly object and a Los Angles water reservoir suddenly turns black.

A giant swastika appears in a forest in Germany, a strange pattern is etched into the desert near the famous Nazca lines and mysterious markings are spotted in an isolated corner of Antarctica.

Satellite images reveal how El Chapo escaped from a high-security prison in Mexico, mysterious patterns in the Australian outback spark a major scientific investigation and a black stain appears in a war-torn area of Iraq.

A giant letter Z carved into a Mexican hillside evokes the mark of a legendary outlaw, a strange sighting in Germany points to secrets from the Cold War and blood red marks in China prompt fears of a violent government crackdown.

A strange creature breaches the surface of the ocean near Antarctica, an area of the US-Mexico border becomes an international mystery and ancient rock carvings in a remote mountain range depict unearthly beings.

An amateur archaeologist stumbles upon strange symbols scratched into the Kazakhstan desert, CIA surveillance photographs show a giant Star of David on the island of Cuba and a lake in Brazil has turned bright pink.

A vast structure near the legendary city of Petra points to a bloody past, and rescuers use satellites to track down kidnapped schoolgirls in northern Nigeria.

New evidence could lead to the discovery of an unknown ancient civilization in the Amazon, a strange photo reveals a massive Arctic canyon buried beneath the ice and an unidentified submarine is spotted in a North Korean shipyard.

A massive chasm in a remote Siberian forest may be a gate to the underworld, an image revealing a strange object at the bottom of a pond could help solve a cold case and an island disappears off the face of the planet.

Strange images from the jungles of Colombia could lead researchers to the legendary city of El Dorado. A bright green swirling spiral appears in the seas of the Persian Gulf. A massive complex suddenly appears secretive state of Myanmar.

Strange images from Colombia could lead researchers to the legendary city of El Dorado, a bright green spiral is spotted in the Persian Gulf and a massive complex appears overnight in the secret state of Myanmar.

A young boy makes international headlines when he discovers lost cities of the Maya, satellite images might point to a modern-day genocide and trees in China seem to be spelling out a sinister message.

A strange arrangement of stones may be connected to a mythical wizard, investigators uncover an anomaly in the Gulf of Mexico and an island appears out of thin air in the Middle East.