Episode 35: SETI and Beyond: A discussion with Brian Keating, Paul Davies, Jim Benford and Mat Kaplan
Books mentioned in this episode:
The Eerie Silence: Renewing Our Search for Alien Intelligence by Paul Davies
The Demon in the Machine: How Hidden Webs of Information Are Solving the Mystery of Life by Paul Davies
Starship Century, Edited by Greggory & James Benford
A technologically advanced extraterrestrial civilization could likely detect life on Earth, if such beings exist. Life on Earth could be detectable in our planet’s atmospheric spectral lines for over a billion years. Most of our atmospheric oxygen is due to life, and can be observed over interstellar distances — across thousands of light-years. Over this long time, many stars have swept near our solar system and Earth. If extraterrestrial intelligence (ETI) on such "nearby” planets did send probes to remotely observe our planet, where in the Solar System should we look to find evidence of their past visitation? The Moon is the obvious, closest place. Another option would be a newly discovered class of co-orbital objects, an equally logical place to locate for observing Earth. These objects approach Earth very closely every year at distances much closer than any large body besides our Moon. They are an ideal way for ET's to watch our world from a secure natural object that provides resources an ET life form might need: materials, a firm anchor, and concealment. They might likely be robotic probes, like our own Voyager and New Horizons probes, remaining on site after exhausting their energy supply. Studying the Moon and co-orbitals could be termed "extraterrestrial archeology". For the Moon, we can use the photographic mapping of the Moon’s surface by the Lunar Reconnaissance Orbiter. Co-orbitals have been little studied by astronomy and not at all by SETI or planetary radar observations.
This discussion describes a strategy of looking for ETI artifacts. It proposes both passive and active observations by optical and radio listening, radar imaging and launching probes. We might even broadcast to them. But what if we find nothing there? That would be a profound result: suggesting that, perhaps, no ET intelligence has yet come to look at Earth, on that other hand, perhaps other civilizations are simply not as curious as we are or are better at concealing their activities than we are. Such speculation forms the basis of this lively conversation between astrophysicist and associate director of the Arthur C. Clarke Center for Human Imagination, Dr Brian Keating (https://www.youtube.com/DrBrianKeating), Prof. Paul Davies, Dr. James Benford and Mat Kaplan (Planetary Society).
James Benford is President of Microwave Sciences, Inc. in Lafayette, California, which does contracting and consulting in High Power Microwaves and space applications of such technologies. His interests include high power systems from conceptual designs to hardware, microwave source physics, electromagnetic power beaming for space propulsion, and experimental intense particle beams. He has a PhD in Physics in plasma physics (UCSD 1969). He is an IEEE Fellow and an EMP Fellow. He has taught 25 courses in High power Microwaves in 9 countries. He has written 10 books. He is the lead author of High Power Microwaves, 3rd Edition, a widely used textbook. He co-edited Starship Century, dealing with the prospect of star travel, an anthology of fact & fiction. See jamesbenford.com.
Paul Davies is Director of the Beyond Center for Fundamental Concepts in Science at Arizona State University. His research spans cosmology, astrobiology and theoretical physics. He has made important contributions to quantum field theory in curved spacetime, with applications to inflationary cosmology and black holes. He was among the first to champion the possibility that microbial life could be transferred between Mars and Earth in impact ejecta. He also runs a major cancer research program funded by the NCI. He is the author of 28 books, including most recently The Eerie Silence: Renewing Our Search for Alien Intelligence and The Demon in the Machine: How Hidden Webs of Information Are Finally Solving the Mystery of Life.
Mat Kaplan loves hosting and producing Planetary Radio. He was just 17 when he got his first job in broadcasting, yet it wasn't until the 2002 premiere of The Society's popular weekly broadcast and podcast series that he combined his twin loves of space and radio. A Planetary Society staff member for more than 15 years, Mat also plans and manages technical support for Planetfest and other major events and webcasts. He hosts live events for Southern California Public Radio called NEXT, and frequently serves as moderator or speaker at space and science gatherings.