The use of embryonic stem cells has ignited fierce debate across the spiritual and political spectrum. But what if we could create manmade stem cells - or find super cells in adults that could forever replace embryonic cells and remove the controversy? Today, we are on the brink of a new era - an age where we may be able to cure our bodies of any illness. Stephen Hawking has spent his life exploring the mysteries of the cosmos, now there is another universe that fascinates him - the one hidden inside our bodies - our own personal galaxies of cells." Hawking takes us on a fascinating journey exploring what these wondrous and baffling mechanisms are capable of. He is joined by the scientists who are on the front lines of discovery in this field including Dr. Doris Taylor who is customizing a donor's heart with the recipient's stem cells - her goal is to revolutionize heart transplants, Dr. Paul Lu and Dr. Mark Tuszynski may have created a breakthrough that could cure paralysis, and Dr. Vincent Giampapa who believes that stem cells can be used to stem the tide of aging and create a fountain of youth.

Follow actor William Shatner through interviews with the other actors who have portrayed starship Enterprise captains in five other incarnations of the Star Trek franchise. Shatner's subjects discuss their lives and careers before, during and after their tenure with Star Trek. With the use of conversations and archival footage, they explore the pressures, stigmas and sacrifices that accompanied their roles and their larger careers. During the process of the film and with help from the other Captains, Sir Patrick Stewart, Avery Brooks, Kate Mulgrew, Scott Bakula and Chris Pine, Shatner overcomes his disdain and learns to embrace his best known character, Captain James T. Kirk.

A humpback whale mother and calf embark on an epic journey from tropical coral paradises to storm ravaged polar seas. Newly discovered coral reefs in Indonesia reveal head-butting pygmy seahorses, flashing 'electric' clams and bands of sea kraits, 30-strong, which hunt in packs. Elsewhere plagues of sea urchins fell forests of giant kelp. Huge bull fur seals attack king penguins, who despite their weight disadvantage, put up a spirited defence.

Open your eyes to the bizarre, ferocious and surprisingly beautiful world of the invertebrates, a ground-breaking exploration into a spectacular miniature universe never normally seen but teeming all around us. In the first episode, the story of the land-living invertebrates. Discover the private life of Europe's dramatic leopard slug, a common garden resident with a truly bizarre end to its marathon mating ritual; watches the courtship ballet of tiny springtails on the underside of a leaf; sees swarms of bright red South African millipedes find partners, and in the caves of Venezuela meets the giant bat-eating centipede.

Take an exhilarating, unprecedented exploration of the seven most amazing wonders of our solar system. Our virtual tour begins with a trip to Enceladus, one of Saturn's outer moons, where icy geysers spout from its surface. Then venture to Saturn's famous rings, which contain mountain ranges that rival the Alps. Next dive into the eye of the biggest storm in the solar system--Jupiter's Great Red Spot. Soar through the Asteroid Belt, containing millions of leftover rocks from the formation of the solar system. Trek up Mount Olympus, the largest volcano, located on Mars. Have a close encounter with the searing surface of the Sun, and finish the journey by exploring our home planet Earth.

In 335 BC Alexander of Macedonia set off on an expedition to conqueror the world. The voyage of Alexander the Great covered more than 22,000 miles in ten years, from Greece to India and back, through some of the most difficult and unforgiving terrain. Michael Wood was hot on his trail, following, as closely as possible, in the footsteps of Alexander and the army that he drove to achieve the impossible. In this programme: the Lebanese city of Tyre, scene of Alexander's most desperate battle; the Palestinian legend of `Two-Horned Alexander'; and the Egyptian oasis of Siwa, where Alexander was proclaimed pharaoh and son of God.