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The World Set Free

   2014    Nature
This episode explores the nature of the greenhouse effect (discovered by Joseph Fourier and Svante Arrhenius), and the evidence demonstrating the existence of global warming from humanity's influence. Tyson begins by describing the long-term history of the planet Venus; based on readings from the Venera series of probes to the planet, the planet had once had an ocean and an atmosphere, but due to the release of carbon dioxide from volcanic eruptions, the runaway greenhouse effect on Venus caused the surface temperatures to increase and boiled away the oceans. Tyson then notes the delicate nature of the amount of carbon dioxide in the atmosphere can influence Earth's climate due to the greenhouse effect, and that levels of carbon dioxide have been increasing since the start of the 20th century. Evidence has shown this to be from mankind's consumption of oil, coal, and gas instead of from volcanic eruptions due to the isotopic signature of the carbon dioxide. The increase in carbon dioxide has led to an increase in temperatures, in turn leading to positive feedback loops of the melting polar ice caps and dethawing of the permafrost to increase carbon dioxide levels. Tyson then notes that humans have discovered means of harvesting solar power, such as Augustin Mouchot's solar-driven motor in the 19th century, and Frank Shuman's solar-based steam generator in the 1910's. Tyson points out that in both cases, the economics and ease of using cheap coal and oil caused these inventions to be overlooked at the time. Today, solar and wind-power systems would be able to collect enough solar energy from the sun easily. Tyson then compares the motivation for switching to these cleaner forms of energy to the efforts of the Space race and emphasizes that it is not too late for humanity to correct its course.
Series: Cosmos: A Spacetime Odyssey

Kurt Cobain Montage of Heck

   2015    Art
Kurt Cobain, lead singer, guitarist, and songwriter of Nirvana, remains an icon 20 years after his death. Here, we take a journey through Cobain's life and his career with Nirvana through the lens of his home movies, recordings, artwork, photography, and journals. An authorized documentary from director Brett Morgen, from Cobain’s early days in Aberdeen, Washington to his success and later downfall with the grunge band Nirvana, this documentary received an award at the 2015 Sundance FilmFestival.

Jacques-Louis David

   2006    Art
Painting became an important means of communication for David since his face was slashed during a sword fight and his speech became impeded by a benign tumour that developed from the wound, leading him to stammer. He was interested in painting in a new classical style that departed from the frivolity of the Rococo period and reflected the moral and austere climate before the French Revolution. David became closely aligned with the republican government and his work was increasingly used as propaganda with the Death of Marat proving his most controversial work.
Series: Power of Art

Meet the Romans: All Roads Lead to Rome

   2012    History
Professor Mary Beard looks beyond the stories of emperors, armies, guts and gore to meet the everyday people at the heart of Ancient Rome's vast empire. In this programme, Mary asks not what the Romans did for us, but what the empire did for Rome. She rides the Via Appia, climbs up to the top seats of the Colosseum, takes a boat to Rome's port Ostia and takes us into the bowels of Monte Testaccio. She also meets some extraordinary Romans: Eurysaces, an eccentric baker, who made a fortune out of the grain trade and built his tomb in the shape of a giant bread oven; Baricha, Zabda and Achiba, three prisoners of war who became Roman citizens; and Pupius Amicus, the purple dye seller making imperial dye from shellfish imported from Tunisia. This is Rome from the bottom up.
Series: Meet the Romans

In Search of Beethoven I

   2009    Art
'In Search of Beethoven': takes a comprehensive look at the composer's life through historical research and Beethoven's biography and letters, but with the emphasis always on the performance -- and interpretation -- of Beethoven's music. From his early piano concertos through the "Moonlight Sonata," "Für Elise," and the immortal notes of the Fifth and Ninth Symphonies, Beethoven's music remains as beloved, popular, and relevant as any work of art has ever been. "In Search of Beethoven" brings together the world's leading performers and experts on Beethoven to reveal new insights into this celebrated composer.
Series: In Search of Beethoven

Hiding in the Light

   2014    Science
This episode explores the wave theory of light as studied by mankind, noting that light has played an important role in scientific progress, with such early experiments from over 2000 years ago involving the camera obscura by the Chinese philosopher Mozi. Tyson describes the work of the 11th century Arabic scientist Ibn al-Haytham, considered to be one of the first to postulate on the nature of light and optics leading to the concept of the telescope, as well as one of the first researchers to use the scientific method. Tyson proceeds to discuss the nature of light as discovered by mankind. Work by Isaac Newton using diffraction through prisms demonstrated that light was composed of the visible spectrum, while findings of William Herschel in the 19th century showed that light also consisted of infrared rays. Joseph von Fraunhofer would later come to discover that by magnifying the spectrum of visible light, gaps in the spectrum would be observed. These Fraunhofer lines would later be determined to be caused by the absorption of light by electrons in moving between atomic orbitals when it passed through atoms, with each atom having a characteristic signature due to the quantum nature of these orbitals. This since has led to the core of astronomical spectroscopy, allowing astronomers to make observations about the composition of stars, planets, and other stellar features through the spectral lines, as well as observing the motion and expansion of the universe, and the existence of dark matter.
Series: Cosmos: A Spacetime Odyssey