Silicon Valley Astronomy Lectures
Free-floating Planets: When You’re Just Too Small to be a Star
Dr. Gibor Basri (University of California, Berkeley)
Listen (mp3 file, 34.4 MB)
The least massive star is six times heavier than the most massive known planet. In between is the realm of the mysterious “brown dwarfs.” The first of these was discovered only in 1995, the same year astronomers found the first planet beyond our solar system. Since then we have found hundreds of each, and new techniques are giving us even more power to probe the properties of these enigmatic bodies. Dr. Basri, one of the discoverers of brown dwarfs, summarizes the progress we have made in understanding the domain of cosmic objects that don’t qualify as stars.
Astronomy from the Stratosphere: NASA’s SOFIA Mission
Dr. Dana Backman (Director of Education & Public Outreach, SOFIA Project, NASA Ames Research Center)
Listen (mp3 file, 28.1 MB)
Why did NASA buy a used passenger airliner, cut a 10′ x 10′ hole in the fuselage, add a roll-back door, and install a 17-ton telescope inside? Dr. Backman introduces us to the engineering marvel called SOFIA — the Stratospheric Observatory for Infrared Astronomy. This remarkable airborne telescope began scientific research flights in 2010 and is already returning exciting discoveries about the birth of stars, interstellar chemistry, the atmospheres of giant planets, the environment around supermassive black holes, and other branches of astronomy.
How Galaxies were Cooked from the Primordial Soup
Dr. Sandra Faber (University of California, Santa Cruz and University of California Observatories)
Listen (mp3 file, 29.5 MB)
The lumpiness of today’s universe of galaxies is a fundamental characteristic that took billions of years to grow. Dr. Faber reviews the prevailing “Cold Dark Matter” theory for galaxy formation (which she helped create) and compares its predictions to present-day observations. It’s a remarkable saga involving invisible dark energy and matter, the properties of the Universe an instant after it was born, and the creation of structure from quantum fluctuations. (Just a few days before giving this talk, Dr. Faber received the 2013 National Medal of Science from President Obama, and she shares an anecdote from that ceremony.)
Black Holes: The End of Time or a New Beginning?
Dr. Roger Blandford (Kavli Institute, Stanford University)
Listen (mp3 file, 32.9 MB)
While black holes are popularly associated with death and doom, astrophysicists increasingly see them as creators, not destroyers — playing a major role in the formation and evolution of galaxies, stars, and planets. Dr. Blandford (whose research interests include black holes, galaxies, and cosmology) summarizes why scientists now think that black holes of various sizes actually do exist, describes some of their strange properties, and explains their “environmental impact” on the universe at large.
Finding the Next Earth: The Latest Results from Kepler
Dr. Natalie Batalha (NASA Ames Res. Ctr.)
Listen (mp3 file, 32.9 MB)
Dr. Batalha (Mission Scientist for the Kepler Mission searching for exoplanets) describes the techniques used by the Kepler team to identify planets orbiting other stars and updates us on the remarkable progress they are making in the search for Earth-sized worlds. She discusses the planets already found and shares what we know so far about the thousands of candidate planets that are in the Kepler data.
Multiple Universes and Cosmic Inflation: The Quest to Understand Our Universe (and Find Others)
Dr. Anthony Aguirre (University of California at Santa Cruz)
Listen (mp3 file, 24 MB)
Our improving understanding of the cosmos points to an early epoch during which the universe expanded at a stupendous rate to create the vast amount of space we can observe. Cosmologist are now coming to believe that this “cosmic inflation” may do much more: in many versions, inflation goes on forever, generating not just our observable universe but also infinitely many such regions with similar or different properties, together forming a staggeringly complex and vast “multiverse”. Dr. Aguirre traces the genesis of this idea, explores some of its implications, and discusses how scientists are seeking ways to test this idea.
Our Explosive Sun: New Views of the Nearest Star and the Largest Explosions in the Solar System
Dr. Thomas Berger (Lockheed Martin Solar and Astrophysics Lab)
Listen (mp3 file, 18.2 MB)
Recent satellite missions are giving scientists dramatic new views of the Sun and the huge magnetic explosions in its outer layers that cause flares and the ejections of huge masses of superheated gas. Dr. Berger takes us on a beautiful tour through our Sun’s atmosphere with images and movies from these missions.
Saturn’s Moon Titan: A World with Rivers, Lakes, and Possibly Even Life
Dr. Chris McKay (NASA Ames Research Center)
Listen (mp3 file, 19 MB)
Titan, Saturn’s largest satellite, is the only moon with a thick atmosphere. In many ways, Titan is a cold twin of the Earth, with liquid methane playing the same role there as water plays on our planet. Life on Earth is based on liquid water; could there be life on Titan based on liquid methane? Dr. McKay (co-investigator on the Huygens probe that landed on Titan) discuss the new picture we have of this alien world, with its lakes, its rivers, and its rocks made of water ice.
How I Killed Pluto and Why It Had it Coming
Dr. Michael Brown (Caltech)
Listen (mp3 file, 19.9 MB)
Dr. Brown shares the inside story of how he discovered “other Pluto’s” out there beyond Neptune, including Eris, which is now known to be about the same size as Pluto. He named that new world for the goddess of discord, because, as he describes with his characteristic humor, its discovery resulted in a private and public controversy that led to a redefinition of what a planet is.
Catching Shadows: Kepler’s Search for New Worlds
Dr. Natalie Batalha (San Jose State University)
Listen (mp3 file, 16.9 MB)
NASA’s Kepler spacecraft, launched in March 2009, is a mission designed to survey a slice of the Milky Way Galaxy to identify planets orbiting other stars. Kepler has the advantage that it can find planets as small as Earth in or near the habitable zone of each star. Dr. Batalha introduces the quest for planets elsewhere, describes the techniques used by the Kepler team, and shares some of the mission discoveries to date.