What on Earth? - Season 12

Satellite images capture a bizarre pattern of enormous circular clouds obscuring the Spanish island of La Palma in the eastern Atlantic. Experts investigate the 2021 Cumbre Vieja volcanic eruption and uncover evidence of an unfolding natural disaster that could potentially threaten millions of lives.

Aerial archaeologists use laser imaging to capture a distinct star-shaped pattern carved into the marsh of a Florida swamp; experts investigate and reveal a lost Civil War fort linked to an extraordinary community with a tragic past.

Satellite images capture a large compound of abandoned structures overgrown with vegetation in Clark County, Indiana. Experts investigate and uncover the Indiana Ordnance Works, a derelict WWII munitions factory that played a crucial role in US military history, producing smokeless gunpowder. In 1964, its name changed to the Indiana Army Ammunition Plant.

Aerial drone imaging captures a circular man-made structure that appears to be centuries-old in the remote forests of Aydin Province in western Turkey. Experts investigate a lost ancient Roman amphitheater with a history steeped in gladiatorial bloodshed.

Satellite images capture a mysterious fortification concealed beneath a patch of woodland in the remote stretches of Norfolk, England. Experts investigate rival royal families and Gresham Castle, a lost castle destroyed during a medieval blood feud.

Satellite images capture miles of rusting military aircraft precisely arranged in the vast Arizona desert, over 4000. Experts investigate Earth's largest aircraft storage facility and the rotting remains of a defining moment in Cold War history.

U.S. Intelligence vastly overestimated the long-range nuclear bomber fleet of the Soviet Union in the 1950s. The U.S. deployed a line of ZPG-3W Airships along the Atlantic for two years for early warning of a Soviet attack. 750 B-52 Stratofortresses eventually were made. Some of these airships are in the boneyard along with 360 B-52s per the 1971 START 1 nuclear treaty.

Satellite images capture an enormous X shape mysteriously carved with precision in the remote Nevada desert. Experts investigate a military emergency landing field linked to one of aviation history's most astonishing test programs, the X-15. It flew over six times the speed of sound and at altitudes over 62 miles high.

A ghost ship appears overnight on the shores of Ireland after a powerful Atlantic cyclone named Storm Dennis in February 2020. The MV Alta was abandoned at sea in October 2018, southeast of the Bermuda Triangle. Could it help shed light on the fate of vessels claimed by the most notorious patch of ocean on Earth? Could its 17-month drift help scientists better understand complex ocean currents?

Satellite images capture a mysterious group of pyramid-shaped structures in Arizona's arid, desert landscape. Experts investigate Biosphere 2, a highly controversial research facility designed to prepare humanity for life on another world.

Aerial archaeologists capture a series of mysterious dots buried beneath the remote, frozen landscape of Finnmark, Norway. Experts investigate and reveal revolutionary reindeer hunting techniques using trapping pits developed by the Sámi, the oldest surviving indigenous Norwegian tribe.