What is the universe made of? If you answered stars, planets, gas and dust, you'd be dead wrong. Thirty years ago, scientists first realized that some unknown dark substance was affecting the way galaxies moved. Today, they think there must be five times our understanding of the universe and the nature of reality itself has drastically changed over the last 100 years - and it's on the verge of another seismic shift. In a 17-mile-long tunnel buried 570 feet beneath the Franco-Swiss border, the world's largest and most powerful atom smasher, the Large Hadron Collider, is powering up. Its goal is nothing less than recreating the first instants of creation, when the universe was unimaginably hot and long-extinct forms of matter sizzled and cooled into stars, planets, and ultimately, us. These incredibly small and exotic particles hold the keys to the greatest mysteries of the universe. What we find could validate our long-held theories about how the world works and what we are made of -- or, all of our notions about the essence of what is real will fall apart.

Are the rings of Saturn a real celestial phenomenon or merely a cosmic Illusion? Technology allows the experts to get closer to the furthest planet visible to the naked eye. Old questions are answered and new ones arise. Does Saturn hold the key to Earth's weather and will one of its moons supply us with all the oil we'll ever need?

The episode, devoted to the planet Mars, begins with scientific and fictional speculation about the Red Planet during the late nineteenth and early twentieth centuries (H. G. Wells' The War of the Worlds, Edgar Rice Burroughs' science fiction books, and Percival Lowell's false vision of canals on Mars). It then moves to Robert Goddard's early experiments in rocket-building, inspired by reading science fiction, and the work by Mars probes, including the Viking, searching for life on Mars. The episode ends with the possibility of the terraforming and colonization of Mars and a Cosmos Update on the relevance of Mars' environment to Earth's and the possibility of a manned mission to Mars.

The magnificent ringed planet Saturn, along with its more than 80 moons, forms the most dynamic planetary system in our neighborhood. With underground oceans and protective magnetic fields, experts are exploring how this collective of satellites has the potential to rewrite the rules of the Solar System.
The closer that we look, the more we see these extraordinary moons like worlds of their own -- so dynamic, so Earth-like. Almost a billion miles from the Sun, these icy worlds could be home for Life 2.0. The moons of Saturn offer possibly the best chance of finding extraterrestrial life in our solar system. With each new mission, we get closer to unraveling the mysteries of Saturn's moons.

Go with us behind the scenes at CERN to follow one of the most epic and expensive scientific quests of all time: the search for the Higgs particle, believed to give mass to everything in our universe. However, the hunt for Higgs is part of a much grander search for how the universe works. It promises to help answer questions like why we exist and is a vital part of a Grand Unified Theory of nature". At the heart of the pursuit of the elusive particle is the same feature that makes snowflakes beautiful and human faces attractive: the simple and enchanting idea of symmetry. Presenter Jim Al-Khalil

A strange light in the heavens. The star that signals the birth of Jesus. Is it faith, fable, or fact? The star of Bethlehem is hard to identify thousands of years later. Can we decode the secret of the star with the science of the universe? What was it? Where did it come from? And will it return?
Discover an explanation by various astronomers and religion historians of what the star of Bethlehem really was based on available evidence.