Astrobiology and SETI

SETI: A Networked Galaxy?

October 9, 2015

We often conceive of SETI scenarios in which Earth scientists pick up a beacon-like signal from another star, obviously intended to arouse our attention and provide information. But numerous other possibilities exist. Might we, for example, pick up signs of another civilization’s activities, perhaps through intercepting electromagnetic traffic, or their equivalent of planetary radars? Even […]

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Seeing Alien Power Beaming

September 25, 2015

We’ve long discussed intercepting not only beacons but stray radio traffic from other civilizations. The latter may be an all but impossible catch for our technology, but there is a third possibility: Perhaps we can intercept the ‘leakage’ from a beamed power infrastructure used to accelerate another civilization’s spacecraft. The idea has been recently quantified […]

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Another Search for Kardashev Type III

September 24, 2015

I have no idea whether we would be able to recognize a Kardashev Type III civilization if we saw one, but the search is necessary as we rule out some possibilities and examine others. As we saw yesterday, the Glimpsing Heat from Alien Technologies project at Penn State has examined data on 100,000 galaxies, finding […]

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No Sign of Galactic Super-Civilizations

September 22, 2015

‘Dysonian SETI’ is all about studying astronomical data in search of evidence of advanced civilizations. As such, it significantly extends the SETI paradigm both backwards and forwards in time. It moves forward because it offers entirely new search space in not just our own galaxy but galaxies throughout the visible universe. But it also moves […]

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A Statistical Look at Panspermia

September 1, 2015

Would panspermia, the idea that primitive life can spread from star to star, be theoretically observable? Henry Lin and Abraham Loeb (both associated with the Harvard-Smithsonian Center for Astrophysics) believe the answer is yes. In a paper accepted for publication in Astrophysical Journal Letters, the duo make the case that panspermia would create statistical correlations […]

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Searching for Extraterrestrial Life and Intelligence: Knowable and Unknowable

July 24, 2015

We recently looked at the $100 million infusion into the SETI effort by Yuri Milner, with backing by major figures in the field. When I’m considering SETI developments, I always look to Michael Michaud, whose judicious perspective in his book Contact with Alien Civilizations (Copernicus, 2007) remains a touchstone. He served in senior international science […]

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A $100 Million Infusion for SETI Research

July 20, 2015

SETI received a much needed boost this morning as Russian entrepreneur Yuri Milner, along with physicist Stephen Hawking and a panel including Frank Drake, Ann Druyan, Martin Rees and Geoff Marcy announced a $100 million pair of initiatives to reinvigorate the search. The first of these, Breakthrough Listen, dramatically upgrades existing search methods, while Breakthrough […]

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The Zoo Hypothesis as Thought Experiment

June 26, 2015

Imagine a civilization one million years old. As Nick Nielsen points out in today’s essay, the 10,000 year span of our terrestrial civilization would only amount to one percent of the older culture’s lifetime. The ‘zoo hypothesis’ considers extraterrestrials studying us as we study animals in controlled settings. Can a super-civilization study a planetary culture […]

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Enter the ‘Warm Titan’

May 20, 2015

Our definition of the habitable zone is water-based, focusing on planetary surfaces warm enough that liquid water can exist there. New work by Steven Benner (Foundation for Applied Molecular Evolution) and colleagues considers other kinds of habitable zones, specifically those supporting hydrocarbons, which can be liquids, solids or gases depending on the ambient temperature and […]

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SETI and Stellar Drift

May 13, 2015

It was natural enough that Richard Carrigan would come up with the model for what he called ‘Fermi bubbles,’ which I invoked in Monday’s post. A long-time researcher of the infrared sky, Carrigan (Fermi National Accelerator Laboratory, now retired) had mined data from the Infrared Astronomical Satellite (IRAS) in 2009 to mount a search for […]

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