Astrobiology and SETI

A New Look at Sea Floor Astrobiology

April 16, 2014

How do you produce life on an early Earth bathed in ultraviolet radiation? The presumption when I was growing up was that the combination of chemicals in ancient ponds, fed energy by lightning or ultraviolet light itself, would produce everything needed to start the process. Thus Stanley Miller and Harold Urey’s experiments, beginning in 1953 […]

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SETI at the Particle Level

February 12, 2014

A big reason why the Fermi paradox has punch is the matter of time. Max Tegmark gets into this in his excellent new book Our Mathematical Universe: My Quest for the Ultimate Nature of Reality (Knopf, 2014), where he runs through what many thinkers on the subject have noted: Our Sun is young enough that […]

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Habitability Around Ancient Stars

February 4, 2014

I see a lot to like about Abraham Loeb’s new paper “The Habitable Epoch of the Early Universe,” available as a preprint and now going through the submission process at Astrobiology. Not that it isn’t controversial, and for reasons that are patently obvious as soon as one digs into it. But the sheer chutzpah of […]

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Is Energy a Key to Interstellar Communication?

November 27, 2013

I first ran across David Messerschmitt’s work in his paper “Interstellar Communication: The Case for Spread Spectrum,” and was delighted to meet him in person at Starship Congress in Dallas last summer. Dr. Messerschmitt has been working on communications methods designed for interstellar distances for some time now, with results that are changing the paradigm […]

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Moving Stars: The Shkadov Thruster

November 26, 2013

Although I didn’t write about the so-called ‘Shkadov thruster’ yesterday, it has been on my mind as one mega-engineering project that an advanced civilization might attempt. The most recent post was all about moving entire stars to travel the galaxy, with reference to Gregory Benford and Larry Niven’s Bowl of Heaven (Tor, 2012), where humans […]

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SETI, METI… and Assessing Risk like Adults

November 12, 2013

David Brin is a familiar name to science fiction readers worldwide, the award-winning author of the highly regarded ‘uplift’ novels that include Startide Rising (1983), The Uplift War (1987) and Brightness Reef (1995). Among his numerous other titles are The Postman (1985), Kiln People (2002) and Existence (2012). But Brin is also known as a […]

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James Benford: Comments on METI

November 11, 2013

Pardon this extended introduction to Jim Benford’s response to Nick Nielsen’s Friday essay, but it comes at a serendipitous time. Jim’s recent online work has reminded me that we in the interstellar community need to work to see that as many resources as possible are made available online. In the absence of specialized bibliographies, useful […]

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SETI, METI, and Existential Risk

November 8, 2013

To broadcast or not to broadcast? The debate over sending intentional signals to other stars continues to simmer even as various messages are sent, with no international policy in place to govern them. Writer Nick Nielsen looks at METI afresh today, placing it in the context of existential risk and pondering the implications of what […]

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SETI: Looking for von Neumann Probes

October 2, 2013

In a recent paper outlining a novel strategy for SETI, Michael Gillon (Université de Liège) makes a statement that summarizes what Robert Forward began saying back in the 1970s and even earlier. Interstellar flight is extraordinarily difficult, but not beyond the laws of physics: Our technology is certainly not yet mature enough to build a […]

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Comet Impacts and the Origin of Life

September 17, 2013

It was back in 2010 that Nir Goldman (Lawrence Livermore National Laboratory) first predicted that the impact of a comet on the early Earth could produce potential life-building compounds like amino acids. Goldman was using computer simulations to make the call, studying molecular dynamics under the conditions of such impacts. He found that the shock […]

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