Extreme Cave Diving (#3705) Duration: 56:46 STEREO TVG (Secondary audio: none)

Follow the charismatic Dr. Kenny Broad as he dives into Blue Holes -- underwater caves that formed during the last ice age when sea level was nearly 400 feet below what it is today. They are Earth's least explored and perhaps most dangerous frontiers. With an interdisciplinary team of climatologists, paleontologists and anthropologists, Broad investigates the hidden history of Earth's climate as revealed by finds in this spectacularly beautiful "alternate universe."

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Hunt for the Supertwister (#3107H) Duration: 54:31 STEREO TVPG

A powerful tornado is a terrifying phenomenon that continues to defy decades of scientific efforts to predict it. During one of the worst tornado seasons on record, a Nova camera team chased across the Midwest, capturing hair-raising footage of highly destructive twisters in action. But this is much more than just another "extreme weather" show, focusing on the efforts of two scientists at the University of Oklahoma to develop radically different approaches to forecasting twisters: one relies on "virtual tornadoes" created inside supercomputers, while the other involves hunting down real-life storms to collect data firsthand (the method that inspired the movie Twister). With jaw-dropping 3-Dgraphics generated by the National Center for Supercomputing Applications, this program features spectacular footage of these terrifying twisters and gives viewers a front-row seat to the risky and thrilling art of storm chasing.

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Oklahoma's Deadliest Tornadoes (#4015H) Duration: 56:16 STEREO TVPG

On May 20th 2013, a ferocious F5 tornado over a mile wide tore through Moore, Oklahoma, inflicting 24 deaths and obliterating entire neighborhoods. It was the third time an exceptionally violent tornado had struck the city in 14 years. Yet predicting when and where these killer storms will hit still poses a huge challenge. Why was 2011 - the worst ever recorded tornado season that left 158 dead in Joplin, Missouri - followed by the quietest ever year of activity prior to the Moore disaster? Can improved radar and warning technology explain why so many fewer died in Moore than in Joplin? And will tornadoes get worse as Earth's climate heats up? In this Nova special, we meet scientists in the front ranks of the battle to understand these extreme weather events. We also meet storm survivors whose lives have been upended, and learn how we can protect ourselves and our communities for the uncertain future.

Ape Genius (#3507H) Duration: 55:34 STEREO TVPG (Secondary audio: DVI)

Chimps, orangutans, gorillas, and bonobos -- seem to have rich emotional lives similar to our own. A new generation of investigators is revealing the mental capabilities of great apes. And our evolutionary next-of-kin are turning out to be far smarter than most experts ever imagined.

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Earth from Space (#4006) Duration: 1:56:46 STEREO TVG (Secondary audio: none)

This film reveals a spectacular new space-based vision of our planet. Produced in extensive consultation with NASA scientists, NOVA takes data from earth-observing satellites and transforms it into dazzling visual sequences, each one exposing the intricate web of forces that sustains life on earth. Viewers witness how dust blown from the Sahara fertilizes the Amazon; how a vast submarine "waterfall" off Antarctica helps drive ocean currents around the world; and how the sun's heating up of the southern Atlantic gives birth to a colossally powerful hurricane. From the microscopic world of water molecules vaporizing over the ocean to the magnetic field that is bigger than Earth itself, this show reveals the astonishing beauty and complexity of our dynamic planet.

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Manhunt - Boston Bombers (#4014H) Duration: 55:16 STEREO TVPG

At 2:50pm on April 15, two bomb blasts turned the Boston Marathon finish line from a scene of triumph to tragedy, leaving 3 dead, hundreds injured, and a city gripped by heartbreak and terror. Less than 5 days later, the key suspects were identified and apprehended - with one dead, the other in custody. How did investigators transform the chaos of the bombing into a coherent trail of clues, pointing to the accused killers?
Nova follows the manhunt step by step, examining the role modern technology - combined with old-fashioned detective work - played in cracking the case. Given hundreds of hours of surveillance and bystander videos, how did agents spot the bad guys in a sea of spectators? Why couldn't facial recognition software I.D. the criminals? How much could bomb chemistry analysis, cell phone GPS, infrared imagery and crowd sourcing reveal about the secrets behind this horrific crime? With the help of top criminal investigators and anti-terrorism experts, Nova explores which technological innovations worked - and which didn't - in the most notorious case of today, and how the world of crime fighting could be transformed tomorrow.

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Dogs Decoded (#3714H) Duration: 56:46 STEREO TVG (Secondary audio: DVI)

Dogs have been domesticated for longer than any other animal on the planet and humans have developed a unique relationship with these furry friends. We treat our pets like a part of the family and we feel that they can understand us in a way other animals cannot. Now, new research is revealing what dog lovers have suspected all along: dogs have an uncanny ability to read and respond to human emotions. What is surprising, however, is new research showing that humans, in turn, respond to dogs with the same hormone responsible for bonding mothers to their babies. How did this incredible relationship between humans and dogs come to be? And how can dogs, so closely related to fearsome wild wolves, behave so differently? It's all in the genes. Nova investigates new discoveries in genetics that are illuminating the origin of dogs - with revealing implications for the evolution of human culture as well. Nova also travels to Siberia, where the mystery of dogs' domestication is being repeated - in foxes. A 50-year-old breeding program is creating an entirely new kind of creature, a tame fox with some surprising similarities to man's best friend. This film reveals the science behind the remarkable bond between humans and their dogs and spurs new questions about what this could mean for our relationships with other animal species.

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Building Pharaoh's Chariot (#4005H) Duration: 56:46 STEREO TVPG

Around 3,600 years ago, reliefs in Egyptian tombs and temples depicted pharaohs and warriors proudly riding into battle on horse-drawn chariots. Some historians claim that the chariot launched a technological and strategic revolution, and was the secret weapon behind Egypt's greatest era of conquest known as the New Kingdom. But was the Egyptian chariot really a revolutionary design? How decisive a role did it play in the bloody battles of the ancient world? In this film, a team of archaeologists, engineers, woodworkers and horse trainers join forces to build and test two highly accurate replicas of Egyptian royal chariots. They discover astonishingly advanced features, including spoked wheels, springs, shock absorbers, anti-roll bars and even a convex shaped rear mirror, leading one of them to compare the level of design to the engineering standards of 1930's-era Buicks! By driving our pair of replicas to their limits in the desert outside Cairo, NOVA's experts test the claim that the chariot marks a crucial turning point in ancient military history.

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Deadliest Earthquakes (#3801H) Duration: 56:46 STEREO TVPG (Secondary audio: DVI)

In 2010, epic earthquakes all over the planet delivered one of the worst annual death tolls ever recorded. The deadliest strike was in Haiti, where a quake just southwest of the capital, Port-au-Prince, killed more than 200,000, reducing homes, hospitals, schools, and the presidential palace to rubble. In exclusive coverage, a Nova camera crew follows a team of US geologists as they first enter Haiti in the immediate aftermath of the tragedy. It is a race against time as they hunt for crucial evidence that will help them determine exactly what happened deep underground and what the risks are of a new killer quake. Barely a month after the Haiti quake, Chile was struck by a quake 100 times more powerful, unleashing a tsunami that put the entire Pacific coast on high alert. In a coastal town devastated by the rushing wave, Nova follows a team of geologists as they battle aftershocks to measure the displacement caused by the earthquake. Could their work, and the work of geologists at earthquake hot-spots around the US, one day lead to a breakthrough in predicting quakes before they happen? Nova investigates new leads in its investigation of a deadly scientific conundrum.

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Ghosts of Machu Picchu (#3704H) Duration: 56:46 STEREO TVPG-V (Secondary audio: DVI)

Perched atop a mountain crest, mysteriously abandoned 400 years ago, Machu Picchu is the most famous archeological ruin in the Western hemisphere and an iconic symbol of the power and engineering prowess of the Inca. In the years since Machu Picchu was discovered by Hiram Bingham in 1911, there have been countless theories about this "Lost City of the Incas," yet it remains an enigma. Why did the Incas build it on such an inaccessible site, clinging to the steep face of a mountain? Who lived among its stone buildings, farmed its emerald green terraces and drank from its sophisticated aqueduct system? NOVA joins a new generation of archeologists as they probe areas of Machu Picchu that haven't been touched since the time of the Incas and unearth burial grounds of the people who built the sacred site.

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B-29 Frozen In Time (#2303) Duration: 56:46 STEREO TVPG (Secondary audio: none)

In 1947, a B-29, on a secret reconnaissance mission over Russia, became lost over the North Pole. The pilot made an emergency landing in Greenland, and the crew was rescued. This program follows pilot Darryl Greenamyer as he heads an expedition into the Arctic to rescue the downed B-29. Battling unpredictable weather, an unforgiving landscape, limited equipment, illness and fatigue, his team rushes to refurbish the plane before the harsh winter sets in. The second half of the program focuses on the Titanic's sister ship, the Brittanic. Few people realize that the Titanic had two nearly identical sister ships, the Olympic and the Britannic. The Olympic had a successful career as a liner until she broke up in 1935, but the Britannic met a fate almost as unlucky as the Titanic's. Serving as a hospital ship in the Aegean, it was either torpedoed or struck a mine on November 21, 1916, and sank within an hour, yet only thirty of the crew of 1,100 died. Nova joins the search for the wreck of the Britannic and explores the evidence of its dramatic end.

3D Spies of WWII (#3903H) Duration: 55:47 STEREO TVPG (Secondary audio: DVI)

Hitler's scientists developed terrifying new weapons of mass destruction. Alarmed by rumors about advanced rockets and missiles, Allied intelligence recruited a team of brilliant minds from British universities and Hollywood studios to a country house near London. Here, they secretly pored over millions of air photos shot at great risk over German territory by specially converted, high-flying Spitfires. Peering at the photos through 3D stereoscopes, the team spotted telltale clues that revealed hidden Nazi rocket bases. The photos led to devastating Allied bombing raids that were crucial setbacks to the German rocket program and helped ensure the success of the D-Day landings. With 3D graphics that recreate exactly what the photo spies saw, NOVA tells the suspenseful, previously untold story of air photo intelligence that played a vital role in defeating Hitler.

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Who Killed Lindbergh's Baby? (#4004#) Duration: 56:46 STEREO TVPG

In the aftermath of his 1927 solo transatlantic flight, Charles Lindbergh became the most famous human being on earth. When he and his wife, Anne, had a son, Charlie, the press dubbed him Little Lindy. On March 1, 1932, kidnappers snatched Little Lindy from the family home near Hopewell, New Jersey. Negotiations stretched out for weeks, but Charlie never returned. His body was discovered not five miles from Hopewell. Now, Nova is reopening one of the most confounding crime mysteries of all time as a team of expert investigators employs state-of-the-art forensic and behavioral science techniques in an effort to determine what really happened to Lindbergh's baby - and why.

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