Last Watched

"Energy"  Sort by

Dark Matter and Dark Energy

   2008    Science
Scientists have no idea what it is, but Dark Matter and Dark Energy make up 96% of the Universe. Dark Matter is everywhere. It passes through everything we know on earth at billions of particles every second, yet no one has ever gotten a direct detection of this mysterious dark substance. An even more bewildering force is Dark Energy, which is rapidly pushing apart our Universe. Discovered only ten years ago, scientists are struggling to comprehend its unusual characteristics and answer the ultimate question; what is the fate of our Universe? Using cutting-edge computer graphics watch as the universe is brought down to earth.
Series: The Universe

Supernovas

   2008    Science
A stellar explosion, the supernova is the sensational death of a star. It can shine as bright as 100 billion Suns and radiate as much energy as the Sun would emit over 10 billion years. Jets of high-energy light and matter are propelled into space and can cause massive Gamma Ray Bursts and emit intense X-ray radiation for thousands of years. Astronomers believe that this process creates the very building blocks of planets, people and plants. Meet the world's leading Supernova hunters, and take a look at recorded supernovas throughout history.
Series: The Universe

Deeper, Deeper, Deeper Still

   2014    Science
This episodes the nature of the cosmos on the micro and atomic scales, using the Ship of the Imagination to explore these realms. Tyson describes some of the micro-organism that live within a dew drop, demonstrating parameciums and tardigrades. He proceeds to discuss how plants use photosynthesis via their chloroplasts to convert sunlight into chemical reactions that convert carbon dioxide and water into oxygen and energy-rich sugars. Tyson then discusses the nature of molecules and atoms and how they relate to the evolution of species. He uses the example set forth by Charles Darwin postulating the existence of the long-tongued Morgan's sphinx moth based on the nature of the comet orchid with pollen far within the flower. He further demonstrates that scents from flowers are used to trigger olfactory centers in the brain, stimulating the mind to threats as to aid in the survival of the species. Tyson narrates how Greek philosophers Thales and Democritus postulated that all matter was made up of combinations of atoms in a large number of configurations, and describes how carbon forms the basic building block for life on earth due to its unique chemical nature. Tyson explains on the basic atomic structure of protons, neutrons, and electrons, and the nature of nuclear fusion that occurs in most stars. He then discusses the existence of neutrinos that are created by these nuclear processes in stars, and that detecting such sub-atomic particles which normally pass through matter require subterranean facilities like the Super-Kamiokande that were used to detect neutrinos from the supernova SN 1987A in the Large Magellanic Cloud before light from the explosion were observed due to their ability to pass through matter of the dying sun. Tyson compares how neutrinos were postulated by Wolfgang Pauli to account for the conservation of energy from nuclear reactions in the same manner as Darwin's postulate on the long-tongued moth. Tyson concludes by noting that there are neutrinos from the Big Bang still existing in the universe but due to the nature of light, there is a "wall of infinity" that cannot be observed beyond.
Series: Cosmos 2014

Unafraid of the Dark

   2014    Science
Tyson describes the discovery of cosmic rays by Victor Hess through high-altitude balloon trips. Swiss Astronomer Fritz Zwicky, in studying supernovae, postulated that these cosmic rays originated from these events instead of electromagnetic radiation. Also tells how Vera Rubin observed that the rotation of stars at the edges of observable galaxies did not follow expected rotational behavior leading to consider the existence of dark matter. This further led to the discovery of dark energy to account for the increasing rate of expansion of the universe. Tyson then describes the interstellar travel of the two Voyager probes. Tyson tells the Carl Sagan's role in the Voyager program, including creating the Voyager Golden Record to encapsulate humanity and Earth's position in the universe. Tyson concludes the series by emphasizing Sagan's message on the human condition in the vastness of the cosmos, and to encourage viewers to continue to explore and discover what else the universe has to offer.
Series: Cosmos 2014

Frozen Planet: Summer

   2011    Nature
It is high summer in the Polar Regions, and the sun never sets. Vast hordes of summer visitors cram a lifetime of drama into one long, magical day; they must feed, fight and rear their young in this brief window of plenty. Summer is a tough time for the polar bear family, as their ice world melts away and the cubs take their first swimming lesson. Some bears save energy by dozing on icy sun beds, while others go egg-collecting in an Arctic tern colony, braving bombardment by sharp beaks. There are even bigger battles on the tundra; a herd of musk oxen gallop to the rescue as a calf is caught in a life and death struggle with a pair of Arctic wolves. But summer also brings surprises, as a huge colony of 400,000 king penguins cope with an unlikely problem - heat. The adults go surfing, while the woolly-coated chicks take a cooling mud bath. Nearby, a bull fur seal is prepared to fight to the death with a rival. Fur flies as the little pups struggle desperately to keep out of the way of the duelling giants. Further south, a minke whale is hunted amongst the ice floes by a family of killer whales. The dramatic chase lasts over 2 hours and has never been filmed before. The killers harry the minke whale, taking it in turns to wear it down. Eventually it succumbs to the relentless battering. Finally, comical adelie penguins waddle back to their half a million strong colony like clockwork toys. The fluffy chicks need constant feeding and protection as piratical skuas patrol the skies. When an unguarded chick is snatched, a dramatic "dogfight" ensues.
Series: Frozen Planet
Nova Wonders
Nova Wonders

   2018    Medicine
History of the World
History of the World

   2012    History
Generation Iron
Generation Iron

   2017    Culture
Africa with David Attenborough
Africa with David Attenborough

   2013    Nature
Life
Life

   2009    Nature
Survivors Guide to Prison
Survivors Guide to Prison

   2018    Culture
The Crusades
The Crusades

   2012    History