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Comet of the Century

   2013    Science
Comet ISON can well be the brightest and most spectacular comet for a generation. It appeared above the eastern horizon from December 2013 as a glorious streak across the sky. ISON has been travelling towards the sun for ten thousand years and will make only one orbit through its corona before disappearing off into the outer solar system.
But as well as providing a great spectacle, ISON's tail of vaporised gas and water, hundreds of millions of kilometres long, will give insights into some of the greatest mysteries of science; it will help explain the origins of the solar system, whether earth's water was delivered on comets and even whether we are alone in the universe.

One Voice in the Cosmic Fugue

   1980    Science
Sagan discusses the story of the Heike crab and artificial selection of crabs resembling samurai warriors, as an opening into a larger discussion of evolution through natural selection (and the pitfalls of intelligent design). Among the topics are the development of life on the Cosmic Calendar and the Cambrian explosion; the function of DNA in growth; genetic replication, repairs, and mutation; the common biochemistry of terrestrial organisms; the creation of the molecules of life in the Miller-Urey experiment; and speculation on alien life (such as life in Jupiter's clouds). In the Cosmos Update ten years later, Sagan remarks on RNA also controlling chemical reactions and reproducing itself and the different roles of comets (potentially carrying organic molecules or causing the Cretaceous–Paleogene extinction event).
Series: Cosmos

Comets: Frozen Wanderers

   2012    Science
We think of comets as beautiful glowing balls of light streaking across our skies with their long sweeping tails, yet comets are so much more than just a cosmic firework display. Comets have a uniquely important place in modern science. As time machines from the early universe, they could hold the key to unlock the secrets of the cosmos. Comets could even be the origin of life itself. We follow the incredible odyssey of a comet as it sails through the solar system, watching it's every move as it evolves from a dormant chunk of ice and rock into a tumbling, violently active nucleus engulfed in a gaseous haze. What we learn is a revelation; comets are even more mysterious and fascinating than we had ever imagined.
Series: How the Universe Works

Mystery of the Alien Asteroid

   2018    Science    HD
When a mysterious cigar-shaped object is spotted tumbling through our solar system, experts race to uncover it's true nature. The object, nicknamed Oumuamua, meaning 'a messenger that reaches out from the distant past' in Hawaiian, was discovered by the Pan-STARRS 1 telescope in Hawaii. Since its discovery, scientists have been at odds to explain its unusual features and precise origins, with researchers first calling it a comet and then an asteroid before finally deeming it the first of its kind: a new class of 'interstellar objects.'
A recent paper by researchers at the Harvard Smithsonian Center for Astrophysics raises the possibility that the elongated dark-red object, which is 10 times as long as it is wide and travelling at speeds of 196,000 mph, might have an 'artificial origin.' The theory is based on the object's 'excess acceleration,' or its unexpected boost in speed as it travelled through and ultimately out of our solar system.
Series: Space Deepest Secrets

Gravity

   2008    Science
Gravity is the most powerful and exacting force in the universe. It is pervasive and penetrating. Gravity binds us together, its reach hangs stars in the sky and its grip crushes light. Gravity holds planets together, and leashes them to their suns. Without gravity, stars, comets, moons, nebulae, and even the Earth itself would not exist. Explore how science and humanity discovered, overcame and utilized gravity. Learn what it takes to propel objects into the heavens, to ride a wave or to ski down a slope. Take a front row seat as an astronaut subjects himself to the weightless wonders of the specially modified aircraft used to train astronauts known as the "Vomit Comet."
Series: The Universe
Walking with Cavemen
Walking with Cavemen

   2003    History
In Search of Beethoven
In Search of Beethoven

   2009    Art
The Nazis, A Warning From History
The Nazis, A Warning From History

   1997    History
The Sky at Night
The Sky at Night

   2018    Science
Wild Russia
Wild Russia

   2009    Nature
How the Universe Works Season 6
How the Universe Works Season 6

   2018    Science
Through the Wormhole Season 8
Through the Wormhole Season 8

   2017    Science
The Universe Season 7
The Universe Season 7

   2014    Science