In a far cry from the steamy jungles of Rwanda or the icy waters of the Arctic, British naturalist Sir David Attenborough has donned a necktie and met with US president Barack Obama to discuss climate change and the future of the planet. The two met at the White House — a place the naturalist had never yet explored — on Sir David's 89th birthday in May to film the interview". It was the first time the respected wildlife filmmaker had met an American president and he seemed a little awed by the experience. Mr Obama, who grew up watching Sir David's programs, seemed equally thrilled. The president has the environment and climate change on his radar and is anxious to see progress made as his presidency comes to a close. He faces stiff opposition from Republicans in Congress on his plans to tackle climate change, but remains determined to make changes before leaving office. "I don't have much patience for anyone who denies that this challenge is real," he said. "We don't have time for a meeting of the Flat Earth Society." Sir David, who has been called "the godfather of natural history TV" by the BBC, brought to the meeting six decades dedicated to sharing the wonders of the natural world with television audiences. After initially being rejected for television because his teeth were deemed "too big", Sir David went on to make his Life on Earth television series, which has been watched by more than 500 million people worldwide. His name is now synonymous with nature, conservation and wildlife. During the television interview, the men discussed global warming, renewable energy and how children and young people hold the key to reversing the damage.

A featured documentary that explores the rise of a new Internet. Decentralized, encrypted, dangerous and beyond the law. The Deep Web, also called the Deep Net, Invisible Web, or Hidden Web is the part of the World Wide Web not indexed by search engines. The deep web was several orders of magnitude larger than the surface web. The majority of the information is hidden or locked inside databases and is growing exponentially at a rate that cannot be quantified. In 2008, to facilitate users of Tor hidden services in their access and search of a hidden .onion suffix, Aaron Swartz designed Tor2web, a proxy application able to provide access by means of common web browsers. Using this application, deep web links appear as a random string of letters followed by the .onion TLD.

August 6th 1945 marked the start of a terrifying new episode in human history. This documentary marks the 70th anniversary of the day when the world's first atomic bomb was dropped on the Japanese city of Hiroshima by a Boeing B-29 USAF Superfortress bomber, nicknamed Enola Gay after the pilot's mother". Up to 80,000 people - 30 per cent of the population - were killed by the blast and resulting firestorm and over 70,000 were injured. This documentary gives a minute-by-minute account of what happened on that fateful day, through the testimony of people who were there and rarely-seen archive footage from the time. Made on location in Hiroshima and the USA, it features unique interviews with eyewitnesses who have seldom, if ever, spoken about the experience. Several of them are no longer alive, they include the last surviving member of the crew of the Enola Gay - navigator Dutch Van Kirk who died in July 2014.

Go with us on a mathematical mystery tour, a provocative exploration of math's astonishing power across the centuries. We discover math's signature in the swirl of a nautilus shell, the whirlpool of a galaxy, and the spiral in the center of a sunflower. Math was essential to everything from the first wireless radio transmissions to the successful landing of rovers on Mars. But where does math get its power?" Astrophysicist and writer Mario Livio, along with a colorful cast of mathematicians, physicists, and engineers, follow math from Pythagoras to Einstein and beyond, all leading to the ultimate riddle: Is math an invention or a discovery? Humankind's clever trick, or the language of the universe? Whether we think we're good with numbers or not, we all use math in our daily lives. The Great Math Mystery sheds fascinating light on how math works in our brains and ponders the ultimate mystery of why it works so well when decoding the universe.

The concept of a digital, decentralized currency is questioning things and the answers being spilled out are deep-seated, long-standing propositions that place a magnifying glass onto the seemingly untouchable financial institutions at the base of modern commerce. What may be uncovered in the philosophical, political, and economic questions could have radical implications for the rest of the 21st century". The documenteray ushers us in, not to explore simply Bitcoin, but to hint at the basis of trade, commerce, and civil society. Director Torsten's story of money is one filled with promise like a sunrise over a landscape of human spirit.

The Celts - one of the world's most mysterious ancient people. In Britain and Ireland, we are never far from our Celtic past but in this series Prof. Alice Roberts and archaeologist Neil Oliver travel much further afield, discovering the origins and beliefs of these Iron Age people in artefacts and human remains right across Europe, from Turkey to Portugal. What emerges is not a wild people on the western fringes of Europe, but a highly sophisticated tribal culture that influenced vast areas of the ancient world - and even Rome". Rich with vivid drama reconstruction, we recreate this pivotal time and meet some of our most famous ancient leaders - from Queen Boudicca to Julius Caesar - and relive the battles they fought for the heart and soul of Europe. Alice and Neil discover that these key battles between the Celts and the Romans over the best part of 500 years constituted a fight for two very different forms of civilisation - a fight that came to define the world we live in today. In the first episode, we see the origins of the Celts in the Alps of central Europe and relive the moment of first contact with the Romans in a pitched battle just north of Rome - a battle that the Celts won and that left the imperial city devastated.