Manhunt - Boston Bombers (#4014H) Duration: 56:46 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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Oklahoma's Killer Tornadoes (#4015H) Duration: 56:46 STEREO

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.

Deadliest Earthquakes (#3801) Duration: 56:46 STEREO TVPG (Secondary audio: none)

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 U.S., 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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Power Surge (#3809) Duration: 56:46 STEREO TVG (Secondary audio: none)

Can emerging technology defeat global warming? The United States has invested tens of billions of dollars in clean energy projects as our leaders try to save our crumbling economy and our poisoned planet in one bold, green stroke. Are we finally on the brink of a green-energy POWER SURGE, or is it all a case of too little, too late? From solar panel factories in China to a carbon capture and storage facility in the Sahara desert to massive wind and solar installations in the United States, NOVA travels the globe to reveal the surprising technologies that just might turn back the clock on climate change. NOVA will focus on the latest and greatest innovations, including everything from artificial trees to green reboots of familiar technologies like coal and nuclear energy. Can our technology, which helped create this problem, now solve it?

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Ape Genius (#3507) Duration: 56:46 STEREO TVPG (Secondary audio: none)

The great apes - which include chimps, orangutans, gorillas and bonobos - seem to have rich emotional lives similar to our own. But just how smart are these animals? A new generation of investigators is revealing the secret mental lives of great apes; our evolutionary next-of-kin are turning out to be far smarter than most experts ever imagined. But just as clever experiments are exposing the extraordinary abilities of great apes, new research is redefining the mental talents of our own species. Scientists are at last zeroing in on what separates us from our closest living relatives.

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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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Ape Genius (#3507H) Duration: 54:08 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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