In World War I, the Germans used cow guts to construct their deadly Zeppelins.

A "cosmic fingerprint" reveals the universe’s beginning and gravity's microscopic secrets.

Explore the social lives of some of the smartest animals on the planet. Airing April 23, 2014 at 9 pm on PBS

What would life on a red dwarf planet look like?

How do dogs, sharks, dolphins, or birds experience the world? Airing April 16, 2014 at 9 pm on PBS

By studying bogs, scientists can uncover thousands of years of Earth’s history.

Birds that craft tools and pick locks are rewriting the rules of animal intelligence. Airing April 9, 2014 at 9 pm on PBS

Why do some dogs have short fur, others long tails, and still others wrinkly faces? Many dogs were bred to perform a specific tasks--from hunting vermin to wrangling bulls--and their physical characteristics were chosen to help them do their jobs.

How do birds manage to fly through narrow spaces without constantly bumping into trees or buildings? It turns out that they use a trick of the eye called optic flow. Understanding what optic flow is and how birds use it could help us build a safer world for our feathered friends.

In recent years, an unusual spate of deadly shark attacks has gripped Australia, resulting in five deaths in ten months. At the same time, great white sharks have begun appearing in growing numbers off the beaches of Cape Cod, Massachusetts, not far from the waters where Steven Spielberg filmed the ultimate shark fright film, Jaws.

Can we return apex predators to their natural environments without endangering humans? Airing April 2, 2014 at 9 pm on PBS

The answer to how you would die in a black hole could revolutionize the laws of nature.

The dome that crowns Florence’s great cathedral of Santa Maria del Fiore—the Duomo—is a towering masterpiece of Renaissance ingenuity and an enduring source of mystery. Still the largest masonry dome on earth after more than six centuries, it is taller than the Statue of Liberty and weighs as much as an average cruise ship.

Who or what killed hundreds of people hidden in a burial chamber nearly 2,000 years ago?

In the rolling hills of Ireland's County Tipperary, a laborer harvesting peat from a dried-up bog spots the remnants of a corpse and stops his machine just in time, revealing a headless torso almost perfectly preserved and stained dark brown by the bog. Archeologists recognize the corpse as one of Europe's rare bog bodies.

Sloths may be cute, but they’re covered in a surprising number of creepy crawlies.

It was the strongest cyclone to hit land in recorded history. On November 8, 2013, Typhoon Haiyan slammed into the Philippines, whipping the low-lying and densely-populated islands with 200 mph winds and sending a two-story-high storm surge flooding into homes, schools, and hospitals. It wiped villages off the map and devastated cities, including the hard-hit provincial capital Tacloban.

In the early days of World War I, Germany, determined to bring its British enemies to their knees, launched a new kind of terror campaign: bombing civilians from the sky. But the aircraft delivering the lethal payloads weren't planes. They were Zeppelins, enormous airships, some the length of two football fields. NOVA investigates the secrets behind these deadly war machines.

It’s a golden age for planet hunters: NASA's Kepler mission has identified more than 3,500 potential planets orbiting stars beyond our Sun. Some of them, like a planet called Kepler-22b, might even be able to harbor life. How did we come upon this distant planet?

Explore an 18th century windmill with a modern day Dutch miller.