24 Hours After: Asteroid Impact

The Day the '60s Died chronicles May 1970, the month in which four students were shot dead at Kent State. The mayhem that followed has been called the most divisive moment in American history since the Civil War. From college campuses, to the jungles of Cambodia, to the Nixon White House, the film takes us back into that turbulent spring 45 years ago.

In 2009 a bizarre story spreads around the globe, reported as fact in the world’s newspapers: Josef Mengele – the infamous escaped Nazi concentration camp doctor, the Angel of Death, may have succeeded in his lifelong goal of creating a blonde, blue-eyed master race. An historian says he has evidence that Mengele’s bizarre experiments on twins may not have ended at Auschwitz, that his efforts to engineer an Aryan master race continued and succeeded while on the run in South America.

Egyptian archaeologists dig into history, discovering tombs and artifacts over 4,000 years old as they search for a buried pyramid in this documentary.

Follow astronaut Scott Kelly's 12-month mission on the International Space Station, from launch to landing, as NASA charts the effects of long-duration spaceflight by comparing him to his identical twin on Earth, astronaut Mark Kelly.

The James Webb Telescope stirs imaginations with vivid photos of distant galaxies. This documentary tracks its historic journey from inception to launch.

James Cameron brings together some the world's leading Titanic experts, including engineers, naval architects, artists and historians, to solve the lingering mysteries of why and how the 'unsinkable' ship sank.

Go behind the scenes with the cast and crew of “Stranger Things: The First Shadow”, the award-winning live stage show that expands the Hawkins universe.

The story of how a fatherless young soldier full of personal ambition becomes a leader of men willing to sacrifice all for the common cause. How a once-loyal British subject rises to battle an empire in a liberty-or-death campaign to forge a new nation. And then how, at the zenith of his power, the victorious general voluntarily steps down, becoming what King George III would call “the greatest man in the world.”

Scientists examine underground clues from over 250,000 years ago that raise questions about our early relatives — and what it truly means to be human.

Does infinity exist? Can we experience the Infinite? In an animated film (created by artists from 10 countries) the world's most cutting-edge scientists and mathematicians go in search of the infinite and its mind-bending implications for the universe. Eminent mathematicians, particle physicists and cosmologists dive into infinity and its mind-bending implications for the universe.

With its four operas, seventeen-hour running time and months of rehearsal, Wagner's "Ring Cycle" is a daunting undertaking for any opera company. Jon Else goes backstage to show this rare event entirely from the point of view of union stagehands at the San Francisco Opera.

Life on the edge in Silicon Valley - home of high tech, high anxiety, and high stakes. Take a revealing look at Netscape Communications engineers as they set out boldly and brazenly to save their company. A virtual panorama of human drama and techno-thrills, Code Rush puts you at the center of the high-intensity clash of science, engineering, and commerce.

This anthology series brings to life Aaron Mahnke's titular podcast and uncovers the real-life events that spawn our darkest nightmares. Blending reenactments, animation, archive and narration, Lore reveals how our horror legends – such as vampires, werewolves and body snatchers – are rooted in truth.

What happens when a machine makes life-or-death decisions? This documentary explores the dangers of artificial intelligence in military application.

They are some of the biggest pyramids on the planet, millions of tons of stone and earth towering above the landscape in a display of massive wealth and power. But it wasn't the pharaohs that built these pyramids. This is the majestic ancient city of Teotihuacán, Mexico, home to one of the most powerful civilizations of its time. But why, around 750 AD, did the advanced civilization that created Teotihuacán suddenly vanish? The identities of its founders, the language they spoke and even the original name of the city are all unknown. DNA analysis of bodies from Teotihuacán shows they weren't Mayan, Incan or Aztec, but an entirely different civilization. It was assumed to have been a peaceful, utopian society, but the latest discoveries are revealing a much darker scenario. In the depths of Teotihuacán's pyramids, experts have uncovered vault after vault filled with curious human remains.

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