The outer solar system and life - Carl Sagan's 1977 Christmas Lectures 2/6

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In his second Christmas lecture, Carl Sagan travels beyond Earth to explore the possibility of life in outer space. Watch all six lectures from this series here: https://www.youtube.com/playlist?list=PLbnrZHfNEDZygWxt60aCWSgDcoazRdTY7 Watch our newest Christmas lectures here: https://www.youtube.com/playlist?list=PLbnrZHfNEDZyQJZLPMjwEoOLdkFBLU2m1 This lecture was filmed at the Ri on Friday 02 Dec 1977. --- From ancient organisms to the plants and animals we see today, our planet showcases a spectacular array of life. But beneath such diversity lies an underlying unity. All life on Earth is based on two molecules (the proteins and the nucleic acids) and the origin of these molecules in the early stages of our planet’s development is inextricably linked to the origin of life. In his second CHRISTMAS LECTURES, Carl Sagan travels beyond Earth to explore the possibility of life in outer space. To find the answer, he looks back to the early stages of the development of our atmosphere. The hydrogen from this atmosphere has since escaped to space from Earth, but not from bigger planets like Jupiter. When the hydrogen-rich gases of the early Earth are mixed together and supplied with energy, the essential molecular building blocks of the proteins and nucleic acids are formed. As Carl suggests, although this process no longer occurs on Earth, such organic chemistry should be occurring in the outer solar system on Jupiter, and Titan, Saturn’s largest moon. The NASA twin spacecraft Voyager 1 and 2, launched a few months prior to these Lectures in 1977, were sent to space to explore this hypothesis. --- CARL SAGAN'S 1977 CHRISTMAS LECTURES: What exists beyond Earth? Over six Lectures presented in 1977, American astronomer and cosmologist Carl Sagan explores the vast expanse of space that surrounds the third planet from the Sun. Life on Earth Where at first we could only discern the size of our planet and some knowledge of its atmosphere and configuration, the evolution of planetary exploration has revealed not only intricate details of Earth’s climate and geology, but a multitude of stars and planets besides our own. Beginning with a closer look at the world we inhabit, Carl explores of the diversity of life on our own planet and the building blocks behind it, before questioning whether the same organic chemistry is occurring on planets in the outer solar system. The Red Planet In Lecture three onwards, Carl takes a closer look at our neighbouring planet, Mars. From early interpretations of terrestrial life on its surface to the surprising discoveries made by NASA’s Viking Program, the Red Planet has become the focus of efforts to discern whether intelligent life exists elsewhere in the universe. When Carl delivered his Lectures in the late 1970s, NASA had only just begun its Voyager program to the furthest planets in our solar system and no extra-solar planets were known to exist. Now, over three decades later, astronomers are looking at planets that lie beyond our solar system to ask the very same question we pondered over Mars: is there life out there? ---- ABOUT THE CHRISTMAS LECTURES: Set up by Michael Faraday when organised education for children was scarce, the Royal Institution CHRISTMAS LECTURES established an exciting new way of presenting science to young people. World-famous scientists have given the Lectures, including Nobel Prize winners William and Lawrence Bragg, Sir David Attenborough, Carl Sagan and Dame Nancy Rothwell. First broadcast in 1936, the CHRISTMAS LECTURES is the oldest science television series. They have been broadcast every year since 1966 on the BBC and in later years on Channel Five, Channel Four and more4. In 2010, the Lectures returned to BBC Four, and this year were shown on the 26th, 27th and 28th of December. Find out more about the lectures here: https://www.rigb.org/christmas-lectures ---- The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and TikTok: https://www.tiktok.com/@ri_science Listen to the Ri podcast: https://podcasters.spotify.com/pod/show/ri-science-podcast Donate to the RI and help us bring you more lectures: https://www.rigb.org/support-us/donate-ri Our editorial policy: https://www.rigb.org/editing-ri-talks-and-moderating-comments Subscribe for the latest science videos: http://bit.ly/RiNewsletter Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link.