NASA's Cassini spacecraft has entered its fifth year exploring the planet Saturn, its rings, and its moons. Dr. Mark Showalter (SETI Institute), a key member of the Cassini science team, shares some of the marvelous results from Saturn and recent discoveries from the mission. His special focus is Saturn's complex and beautiful ring system (which shows a variety of surprising phenomena, including "jets", "propellers", "wisps", "spokes", and "braids") and the remarkable interactions between Saturn's rings and moons. Recorded November 12, 2008.

Saturn's Restless Rings: Latest Results from the Cassini Mission

Public lectures by noted astronomers on new developments in our exploration of the universe. These lectures are recorded at Foothill College near San Francisco.

Natural Sciences

Science & Medicine

Social Sciences

Medicine

In 2004, Craig Venter and Daniel Cohen suggested that if the 20th Century was the century of physics, the 21st Century will be the century of biology on our planet. Jill Tarter believes that their idea will be extended beyond the surface of our world and that we may soon have the first opportunity to study biology that developed on other worlds. She talks about her vision of the future of understanding life on Earth and beyond our planet. And she discusses projects that are underway and are planned to learn more about the possibility of intelligent life among the stars. Recorded October 11, 2017.

Will the 21st Century be the Time We Discover Life Beyond Earth?

On August 21, 2017, there will be a rare eclipse of the Sun visible throughout the U.S. and North America. Andrew Fraknoi, Foothill College, describes how eclipses work and when and where the eclipse of 2017 will be best visible. Recorded May 24, 2017.

The ‘All-American’ Eclipse of the Sun this August

By measuring the rapid orbits of the stars near the center of our galaxy, Dr. Andrea Ghez and her colleagues have moved the case for a supermassive black hole at the heart of the Milky Way from a possibility to a certainty. Recorded January 25, 2017.

The Monster Black Hole at the Center of the Milky Way Galaxy

Prof. Cominsky presents an introduction to LIGO, to gravitational waves and how they were detected, and to the kinds of black holes that “make waves.” Recorded November 2, 2016.

Space-time Symphony: Gravitational Waves from Merging Black Holes

Seth Shostak takes a look at Star Wars and other science fiction films from the point of view of a skeptical scientist, tells stories about the movies he has been asked to advise, and muses about aliens from space. Recorded October 12, 2017.

Saturn's Restless Rings: Latest Results from the Cassini Mission

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