Silicon Valley Astronomy Lectures
The Many Mysteries of Antimatter
Dr. Helen Quinn (Stanford University)
Listen (mp3 file, 17.7 MB)
Antimatter is just like matter with all its properties reversed. Scientists think there may have been equal amount of matter and antimatter in the early universe, and yet today we have lots of matter and very little antimatter. How and when that imbalance developed is one of the great mysteries in understanding the underlying properties of the universe. Dr. Quinn, Professor of Physics at the Stanford Linear Accelerator and co-author of a popular book on antimatter, discusses the history of our understanding of antimatter and how we use the little bit of antimatter around today to study some of the highest energy processes among the stars and galaxies. (This talk is a bit more technical than our usual lectures, but well worth exploring if you are interested in some of the most exciting frontiers of physics.)
The Search for Intelligent Life Among the Stars: New Strategies
Dr. Seth Shostak (SETI Institute)
Listen (mp3 file, 20.5 MB)
A half-century ago, astronomers began trying to “eavesdrop” for radio messages from nearby star systems. However, today, SETI researchers continue to point their telescopes at individual stars, on the assumption that technically advanced societies will inhabit a watery world like our own. Seth Shostak describes these searches, but then discusses some novel ideas for how we might pursue the hunt for “cosmic company” and why it’s possible that we might find evidence of sophisticated intelligence out there within only a few decades. Seth Shostak is Senior Astronomer at the SETI Institute, in Mountain View, California and hosts the syndicated radio show called “Are We Alone?”
Life at the Edge: Life in Extreme Environments on Earth and the Search for Life in the Universe
Dr. Lynn Rothschild (NASA Ames Research Center)
Listen (mp3 file, 20.6 MB)
Astrobiologist Lynn Rothschild has gone from the Bolivian Andes to the Rift Valley of Kenya searching for the hardiest of organisms in the most extreme environments for life. By getting to know life forms on Earth that can occupy the most hostile niches, we can begin to understand the survival requirements for life in general. She describes her quest for “life at the edge” and how such discoveries will shape our search for life in the Solar System and beyond.
Hubble Breakthrough: The First Photos of a Planet Orbiting Another Star
Dr. Paul Kalas (University of California, Berkeley)
Listen (mp3 file, 15.4 MB)
Paul Kalas was the leader of the team who managed the long-sought feat of actually taking a photograph of a planet orbiting another star. Before this, all the planets outside our solar system were found by indirect means. He describes how they achieved the breakthrough, using the Hubble Space Telescope, and discusses the wide range of planets out there that astronomers are discovering.
The Dark Side of the Universe: Dark Matter and Dark Energy
Dr. Patricia Burchat (Stanford University)
Listen (mp3 file, 19.4 MB)
In the last decade or so, astronomers have been forced to accept two mysterious observations. About a quarter of the universe is made of “dark matter,” which attracts things with its gravity, but is otherwise invisible. And roughly two-thirds of the universe is composed of “dark energy,” which causes space itself to expand at an ever-increasing rate. That means only a small fraction of the universe is made of ordinary matter — the stuff we understand! In this non-technical presentation, Dr. Burchat explores the evidence for the dark side of the cosmos, and the experiments that are being developed to investigate it further.
Planetary Protection and Hitchhikers in the Solar System: The Danger of Mingling Microbes
Dr. Margaret Race (SETI Institute)
Listen (mp3 file, 20.2 MB)
Scientists searching for life elsewhere have to worry about avoiding harmful cross contamination during the exploration of planets and their moons. We don’t want to take Earth microbes to Mars or bring back alien microbes to Earth. In this timely talk, Dr. Race gives a behind-the-scenes view of “environmental management” planning for solar system missions, and explains the role of the Outer Space Treaty and other related national and international policies in planning our hunt for life-forms out there.
The Dawn of Creation: The First Two Billion Years
Dr. Stephen Beckwith (University of California)
Listen (mp3 file, 26.4 MB)
All the great islands of stars got their start in the first billion years after the beginning of time, the Big Bang. Every deep picture of the sky reveals thousands of these galaxies, each made up of billions of stars like the Sun. Modern instruments like the Hubble Space Telescope have made it possible to look back to a time when the universe looked very different that it does today. Dr. Beckwith discusses some of the deepest images of the universe ever taken and shares recent discoveries about the early days of the cosmos.
Prospecting for Water on the Moon: The Upcoming LCROSS Mission
Dr. Anthony Colaprete (NASA Ames Research Center)
Listen (mp3 file, 16.8 MB)
In 2009, NASA will purposely crash two spacecraft into one of the Moon’s polar regions. The impacts should raise huge plumes of material, visible even to smaller telescopes on Earth. Dr. Colaprete, the Principal Investigator for this intriguing mission, fills us in on why scientists believe there is water in deep craters at the Moon’s poles and how the LCROSS mission plans to look for it in the plumes.
Saturn’s Restless Rings: Latest Results from the Cassini Mission
Dr. Mark Showalter (SETI Institute)
Listen (mp3 file, 20.7 MB)
NASA’s Cassini spacecraft has entered its fifth year exploring the planet Saturn, its rings, and its moons. Dr. Showalter, 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.
The Black Hole Wars: My Battle with Stephen Hawking
Dr. Leonard Susskind (Stanford University)
Listen (mp3 file, 20.2 MB)
Black holes, the collapsed remnants of the largest stars, provide a remarkable laboratory where the frontier concepts of our understanding of nature are tested at their extreme limits. For more than two decades, Professor Susskind and a Dutch colleague have had a running battle with Stephen Hawking about the implications of black hole theory for our understanding of reality — a battle that he has described in his well-reviewed book The Black Hole Wars. In this talk Dr. Susskind tells the story of these wars and explains the ideas that underlie the conflict. What’s at stake is nothing less than our understanding of space, time, matter and information!