On the tenth anniversary of 9/11, NOVA presents an epic story of engineering, innovation and the perseverance of the human spirit. With extraordinary access granted by The Port Authority of New York and New Jersey, "Engineering Ground Zero" follows the five-year construction of One World Trade Center (1 WTC) and the National September 11 Memorial & Museum. NOVA captures the behind-the-scenes struggle of architects and engineers to make the buildings safe and secure under the pressures of a tight schedule, the demands of practical office space and efficient "green" architecture, and the public's expectations of a fitting site for national remembrance. The program features interviews with 1 WTC architect David Childs; Chris Ward, executive director of the Port Authority of New York and New Jersey; Mayor Michael Bloomberg, chairman of the 9-11 Memorial Foundation; and Michael Arad, the man behind the breakthrough concept for the 9-11 Memorial.

The earthquake that hit the northern coast of Japan on March 11, 2011, was recorded at magnitude 9.0 - the worst ever recorded in Japan. It generated an unprecedented tsunami, obliterating coastal villages and towns in a matter of minutes. In some areas, the tsunami climbed above 100 feet in height and traveled miles inland. Amazingly, amateur and professional photographers captured it all on video, including remarkable tales of human survival, as ordinary citizens became heroes in a drama they never could have imagined. As the waves rush in, a daughter struggles to help her elderly mother ascend their rooftop to safety; a man climbs onto an overpass just as the wave overtakes his car. These never-before-seen stories are captured in video and retold after the fact by the survivors who reveal what they were thinking as they made their life-saving decisions. Their stories provide lessons for how we should all act in the face of life-threatening disasters.

Scientists are on the verge of answering one of the greatest questions in history: Are we alone? Combining the latest telescope images with dazzling CGI, "Finding Life Beyond Earth" immerses audiences in the sights and sounds of alien worlds, while top astrobiologists explain how these places are changing how we think about the potential for life in our solar system. We used to think our neighboring planets and moons were fairly boring - mostly cold, dead rocks where life could never take hold. Today, however, the solar system looks wilder than we ever imagined. Powerful telescopes and unmanned space missions have revealed a wide range of dynamic environments - atmospheres thick with organic molecules, active volcanoes and vast saltwater oceans. This ongoing revolution is forcing scientists to expand their ideas about what kinds of worlds could support life. If we do find primitive life forms elsewhere in the solar system, it may well be that life is common in the universe - the rule, and not the exception.

He's been dead for more than 5,000 years - and been poked, prodded and probed by scientists for the last 20. Yet today, Otzi the Iceman, the famous mummified inactive person pulled from a glacier in the Italian Alps nearly two decades ago, continues to keep many secrets. Now, through an autopsy like none other, scientists will attempt to unravel more mysteries from this ancient mummy, revealing not only the details of Otzi's passing, but an entire way of life. How did people live during Otzi's time, the Copper Age? What did they eat? What diseases did they cope with? The answers abound miraculously in this one man's mummified remains. Join NOVA to defrost the ultimate time capsule, the 5,000-year-old man.

Space. It separates you from me, one galaxy from the next, and atoms from each other. It is everywhere in the universe. But to most of us, space is nothing, an empty void. Well, it turns out space is not what it seems. From the passenger seat of a New York cab driving near the speed of light to a pool hall where billiard tables do fantastical things, Brian Greene reveals space as a dynamic fabric that can stretch, twist, warp, and ripple under the influence of gravity. Stranger still is a newly discovered ingredient of space that actually makes of 70% of the universe. Physicists call it dark energy because while they know it's out there, driving space to expand ever more quickly, they have no idea what it is. Probing space on the smallest scales only makes the mysteries multiply down there, things are going on that physicists today can barely fathom. To top it off, some of the strangest places in space, black holes, have led scientists to propose that like the hologram on your credit card, space may just be a projection of a deeper two-dimensional reality, taking place on a distant surface that surrounds us. Space, far from being empty, is filled with some of the deepest mysteries of our times.

Time. We waste it, save it,hug it, make it. The world runs on it. Yet, ask physicists what time actually is, and the answer might shock you: They have no idea. Even more surprising, the deep sense we have of time passing from present to past may be nothing more than an illusion. How can our understanding of something so familiar be so wrong? In search of answers, Brian Greene takes us on the ultimate time traveling adventure, hurtling 50 years into the future before stepping into a wormhole to travel back to the past. Along the way, he will reveal a new way of thinking about time in which moments past, present, and future-from the reign of T.Rex to the birth of your great-great-grandchildren-exist all at once. This journey will bring us all the way back to the Big Bang, where physicists think the ultimate secrets of time may be hidden. You'll never look at your wristwatch the same way again.

Join Brian Greene on a wild ride into the weird realm of quantum physics, which governs the universe on the tiniest of scales. Greene brings quantum mechanics to life in a nightclub like no other, where objects pop in and out of existence and things over here can affect others over there, instantaneously-without anything crossing the space between them. A century ago, during the initial shots in the quantum revolution, the best minds of a generation-including Albert Einstein and Niels Bohr-squared off in a battle for the soul of physics. How could the rules of the quantum world, which work so well to describe the behavior of individual atoms and their components, appear so dramatically different from the everyday rules that govern people, planets, and galaxies? Quantum mechanics may be counterintuitive, but it's one of the most successful theories in the history of science, making predictions that have been confirmed to better than one part in a billion, while also launching the technological advances at the heart of modern life, like computers and cell phones. But even today, even with such profound successes, the debate sill rages over what quantum mechanics implies for the true nature of reality.

Hard as it is to swallow, cutting-edge theories are suggesting that our universe may not be the only universe. Instead, it may be just one of an infinite number of worlds that make up the multiverse. Brian Greene takes us on a tour of this brave new theory at the frontier of physics, explaining why scientists believe it's true and showing what some of these alternate realities might be like. Some universes may be almost indistinguishable from our own; others may contain variations of all of us, where we exist but with different families, careers and life stories. In still others, reality may be so radically different from ours as to be unrecognizable. Brian Greene reveals why this radical new picture of the cosmos is getting serious attention from scientists. It won't be easy to prove, but if it's right, our understanding of space, time and our place in the universe will never be the same.

Millions of people around the world live in the shadow of active volcanoes. Under constant threat of massive volcanic eruptions, their homes and their lives are daily at risk from these sleeping giants. From Japan's Mount Fuji to the "Sleeping Giant" submerged beneath Naples to the Yellowstone "supervolcano" in the United States, we will travel with scientists from around the world who are at work on these sites, attempting to discover how likely these volcanoes are to erupt, when it might happen, and exactly how deadly they could prove to be.

In 1943 a squadron of Lancaster bombers staged one of the most audacious raids in military history: destroying two gigantic dams in Germany's industrial heartland and cutting the water supply to arms factories. Their secret weapon? A revolutionary bouncing bomb invented by British engineer Barnes Wallis. Wallis and the pilots of 617 Squadron-a lively mix of Britons, Australians, Americans, and Canadians-were hailed as heroes who dealt a mighty blow to the German war machine. Now, NOVA recreates the extreme engineering challenges faced by Wallis and the pilots. A crack team of experts, including dam engineers, explosives specialists, mechanics, and aircrew, steps into the shoes of the "dambusters" and attempts to overcome each of the obstacles the original team faced. They must adapt a vintage World War II DC-4 to carry a bomb the size of an oil drum, train to drop it from a dangerously low altitude in pitch darkness, and get it to bounce over obstacles and onto the target, a scale model the German dam struck by the original dambusters. Can they succeed in destroying the dam and unraveling the mysteries of the one-of-a-kind bouncing bomb?

During World War II, Hitler's scientists developed terrifying new weapons of mass destruction. Alarmed by rumors of 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 dealt 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 the Nazis.

In October 2007, a striking portrait of a young woman in Renaissance dress made world news headlines. Originally sold nine years before for around ,000, the portrait is now thought to be an undiscovered masterwork by Leonardo da Vinci worth more than 0 million. How did cutting-edge imaging analysis help tie the portrait to Leonardo? NOVA meets a new breed of experts who are approaching "cold case" art mysteries as if they were crime scenes, determined to discover "who committed the art". And it follows art sleuths as they deploy new techniques to combat the multibillion-dollar criminal market in stolen and fraudulent art.

In a race against developers in the Rocky Mountains, archeologists uncover a unique fossil site packed with astonishingly well-preserved bones of mammoths, mastodons, and other giant extinct beasts. The discovery opens a highly focused window on the vanished world of the Ice Age in North America.

This is the incredible story of Trishna and Krishna, twin girls born joined at the head. Abandoned shortly after birth at an orphanage in Bangladesh, they had little chance of survival, until they were saved and taken to Australia by an aid worker. After two years battling for life, the twins are ready for a series of delicate operations, which will prepare them for the ultimate challenge: a marathon separation surgery that will allow them to live truly separate lives. Since the beginning, surgeons knew there was no guarantee of survival for either of the girls - but without surgery there was no hope at all. With exclusive access to this extraordinary human and medical drama, NOVA's cameras have been with Trishna and Krishna and their caregivers at each moment of their journey.

What will it mean when most of us can afford to have the information in our DNA-all three billion chemical letters of it-read, stored, and available for analysis? In "Cracking Your Genetic Code", NOVA reveals that we stand on the verge of a revolution. We meet cancer patients returned to robust health and a cystic fibrosis sufferer breathing easily because scientists have been able to pinpoint and neutralize the genetic abnormalities underlying their conditions. What are the moral dilemmas raised by the new technology? Will it help or hurt us to know our genetic destiny? What if such information falls into the hands of insurance companies, employers, and prospective mates? One thing is for certain: The new era of personalized, gene-based medicine is relevant to everyone. Soon, all of us may be deciding whether to join the ranks of the DNA generation.

What are things made of? It's a simple question with an astonishing answer. Fewer than 100 naturally occurring elements form the ingredients of everything in our world - from solid rocks to ethereal gases, from scorching acids to the living cells in our body. David Pogue, lively host of NOVA's popular "Making Stuff" series and personal technology correspondent for The New York Times, spins viewers through the world of weird, extreme chemistry on a quest to unlock the secrets of the elements. Why are some elements, like platinum and gold, relatively inert, while others, like phosphorus and potassium, are unhappyly explosive? Why are some vital to every breath we take, while others are potentially lethal? Punctuated by surprising and often alarming experiments, David Pogue takes NOVA on a roller coaster ride through nature's hidden lab and the compelling stories of discovery that revealed its secrets.

In April 2011, the worst tornado outbreak in decades left a trail of destruction across the U.S., hugging more than 360 people. Why was there such an extreme outbreak? How do such outbreaks form? With modern warning systems, why did so many die? Is our weather getting more extreme-and, if so, how bad will it get? In this NOVA special, we meet scientists striving to understand the forces at work behind last year's outbreak. Could their work improve tornado prediction in the future? We also meet people whose lives have been upended by these extreme weather events and learn how we all can protect ourselves and our communities for the future.

Are you safe aboard a modern cruise ship? Twenty million passengers embark on cruises each year, vacationing in deluxe "floating cities" that offer everything from swimming pools to shopping malls to ice skating rinks. And the ships just keep getting bigger: The average cruise ship has doubled in size in just the last 10 years. Some engineers fear that these towering behemoths are dangerously unstable, and the recent tragedy of the Costa Concordia has raised new questions about their safety. Now, NOVA brings together marine engineering and safety experts to reconstruct the events that led up to famous cruise disasters, including the ill-fated Concordia, the Sea Diamond and the Oceanos. Are we really safe at sea-or are we on the brink of a 21st century Titanic?

It contains 99.9 percent of all the matter in our solar system and sheds hot plasma at nearly a million miles an hour. The temperature at its core is a staggering 27 million degrees Fahrenheit. It convulses, it blazes, it sings. You know it as the sun. Scientists know it as one of the most amazing physics laboratories in the universe. Now, with the help of new spacecraft and Earth-based telescopes, scientists are seeing the sun as they never have before and even recreating what happens at its very center in labs here on Earth. Their work will help us understand aspects of the sun that have puzzled scientists for decades. But more critically, it may help us predict and track solar storms that have the power to zap our power grid, shut down telecommunications, and ground global air travel for days, weeks, or even longer. Such storms have happened before-but never in the modern era of satellite communication. "Secrets of the Sun" reveals a bright new dawn in our understanding of our nearest star-one that might help keep our planet from going dark.