The theory of Némesis, a star that orbits the Sun and causes catastrophic events is explored. Nemesis is a hypothetical red dwarf or brown dwarf, originally postulated in 1984 to be orbiting the Sun at a distance of about 95,000 AU (1.5 light-years) somewhat beyond the Oort cloud, to explain a perceived cycle of mass extinctions in the geological record, which seem to occur more often at intervals of 26 million years.
Category: Science Duration: 44:00
The contests between predators and prey are the most dramatic events in nature. Taking an intimate and detailed look at the remarkable strategies employed by hunters to catch their prey and the hunted to escape. Sir David Attenborough narrates. "The Hardest Challenge" reveals the extraordinary range of techniques predators use to catch their prey - from a leopard using all its powers of stealth to stalk impala in broad daylight to wild dogs, whose tactic is to wear down their prey over long distances; from Nile crocodiles, the planet's most patient predators, to killer whales who use teamwork and intelligence to take on humpback whales. But even with these finely tuned strategies, the outcome is far from certain. Surprisingly, most predators fail most of the time.
Category: Nature Duration: 58:07
Professor Jim Al-Khalili continues his investigation of the atom by looking at radioactivity, the Atom Bomb and the Big Bang, and even why we are here and how we were made. He shows that, in the quest to understand the atom, the mystery of how the entire universe was created became revealed
Category: Science Duration: 58:35
For centuries, man has yearned for an earthly paradise, and no place better encapsulates this desire than Shangri-La - but was it ever real? The tale of an earthly paradise is among the most enduring myths in the world. From Sumerian epic to the 'islands of the blest' in Celtic literature, it has been a recurring theme through many bodies of literature and for thousands of years. Not surprisingly, then, modern people have also been drawn to the dream of a lost paradise where the ravages of time and history have been held back, where human beings live in harmony with nature, and where the wisdom of the planet is saved for future generations. In other words, to a Shangri-La.
Category: History Duration: 60:00
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