Dan Snow uncovers the lost Vikings in America with space archaeologist Dr Sarah Parcak. Sarah uses satellites 383 miles above the earth to spot ruins as small as 30cm buried beneath the surface. As Sarah searches for Viking sites from Britain to America, Dan explores how they voyaged thousands of miles when most ships never left the shoreline. He also tracks their expansion west, first as raiders and then as settlers and traders throughout Britain and beyond to Iceland and Greenland. In North America they excavate what could be the most westerly Viking settlement ever discovered.

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.

See as never before in this series the inner workings of our world, and explore black holes, supernovae, neutron stars, dark energy, and all the titanic forces that make us. A users guide to the cosmos from the big bang to galaxies, stars, planets and moons. Where did it all come from and how does it all fit together. A primer for anyone who has ever looked up at the night sky and wondered". Beneath the hood of your car lies the history of the Universe. The iron in your chassis, the gold in your stereo and the copper in your electronics all owe their existence to violent cosmic events that took place billions of years ago.

There is a hellish planet in our solar system; covered in thick dense clouds and roasted by colossal temperatures. It will be inevitable that the Earth will someday not only be like Venus, but actually put it to shame. A billion years from now, Earth's oceans will boil off, triggering a runaway greenhouse effect, and the temperature will be so high, its all surface will melt. In the distance future, Earth could be the evil twin of Venus. To understand how our world will be destroyed we need to look at what happened to Venus.

Imagine a world where infinite copies of you are playing out every storyline of your life. It sounds like a plot stolen straight from Hollywood, but far from it. This is the multiverse. Until very recently the whole idea of the multiverse was dismissed as a fantasy, but now this strangest of ideas is at the cutting edge of science. And for a growing number of scientists, the multiverse is the only way we will ever truly make sense of the world we are in. Do multiple universes exist? And if so, which one are we actually in?" Imagine a world where dinosaurs still walk the earth. A world where the Germans won World War II and you are president of the United States. Imagine a world where the laws of physics no longer apply.

Every day our planet faces cataclysmic events that threaten our very existence. Whether from natural or man-made forces, rising from the earth or menacing from space, the world seems beset by more catastrophes than ever. Some believe the signs of the coming Apocalypse are all around us–as outlined in the bible’s most compelling book of prophecies: Revelation". And even the non-religious can’t ignore what appears to be a growing rate of globe-threatening disasters. Are we approaching a biblical “End of Times”? And if so–how will it happen? Will it come from an act of God? Or a colossal misstep of man? Get an uncomfortably close front row seat to some of the most likely apocalyptic scenarios our world faces today–and the history, both scientific and biblical, behind them.