Former SETI Chairman Thinks Extraterrestrial Probes May Be Watching Us?

·1 hr 23 min·5 clips

Gertz argues that radio SETI is “a lousy strategy” because probes would be cheaper and more efficient than broadcasting.

1. Nature and Science Podcast centers this episode on John Gertz’s case for replacing radio SETI with probe-based searches for extraterrestrial intelligence. 2. John Gertz is the guest, a longtime SETI board chairman and president of a new organization that raised $100 million for SETI research, while Jill Tarter, Frank Drake, Paul Allen, and David Brin are central named figures in the discussion. 3. The episode asks whether “we are alone in this universe” and whether extraterrestrials may already be watching Earth with probes instead of radio transmitters. 4. Gertz says he entered SETI through cosmology, astronomy, comparative mythology, and a chance meeting with Jill Tarter in the Bay Area around the turn of the millennium. 5. He recounts a birthday dinner where Tarter originally came to ask for money for a telescope and instead recruited him onto the SETI Institute board. 6. He explains that the telescope became the Allen Telescope Array, named after chief funder Paul Allen. 7. Gertz says the classic SETI model was to point a radio telescope star by star and look for an artificial beacon from another civilization. 8. He says that approach has now covered “probably certainly over a million stars” once foreground and background stars are counted. 9. He argues that the result is “downright perplexing” because the search has come up empty across multiple institutions and countries, including Berkeley, Oxford University, Penn State, UCLA, Italy, South Africa, and China’s FAST telescope. 10. He says the old paradigm is “simply bankrupt” and that extraterrestrials would likely choose infrared, ultraviolet, x-ray, or probe-based communication instead of radio. 11. Gertz argues that a civilization billions of years older than Earth would have no reason to keep broadcasting to a young planet that cannot yet respond. 12. He says robotic probes in the solar system could have begun arriving billions of years ago and revisiting Earth as life progressed from single-celled forms to multicellular life. 13. He extends that idea to a network of probes around stars and between stars, with information moving through the galaxy like a linked relay system. 14. He says these probes could upload data from Earth, learn from sources like Sesame Street, Khan Academy, and YouTube, and eventually communicate in real time. 15. He adds that the probes might not be autonomous and could instead report to a progenitor or nodal civilization thousands of light-years away. 16. He says the “I Love Lucy” case is a special exception because human television broadcasts have been going out for about 70 years, creating a possible 35-light-year window. 17. The tone is interview-based and argumentative, with long back-and-forth exchanges, interruptions, and repeated restatements of the probe thesis. 18. The style is explanatory and speculative, but Gertz repeatedly grounds points in numbers such as 13 billion years, 4.55 billion years, 35 light years, and 200 billion to 400 billion stars. 19. People interested in SETI, Drake’s equation, and alien communication models will get the most from this episode. 20. Listeners wanting a fast entertainment interview with little astronomy detail may skip it.

As heard by us

A steady SETI conversation that makes the scale of the search feel concrete.

John Gertz treats SETI as a practical question, not a glossy one: if advanced probes were watching us, what could they really learn, and how far away would Earth need to be before it became readable?

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Press play if you want SETI explained through a clear, science-first conversation.

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