Broadcast 3803 Dr. Lee Cronin, Bill Gowan

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NOTE:  We experienced two dropped calls with our guest but we were quickly able to reconnect with him.  We apologize for the disruption.  Fortunately, our co-host Bill Gowan kept the show going while I went through the process to reconnect with our guest.

Additionally, I want to thank co-host Bill for his work on the summary of this show.  Bill's work is below and it is superb and accurate.

Guest:  Dr. Lee Cronin with co-host Bill Gowan from The Space Show; Topics:  Dr. Cronin's work with molecular complexity and his Molecular Assembly index for searching for life, defining, life, making molecules through chemistry, biomarkers and more.

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We welcomed Dr. Lee Cronin from the University of Glasgow, Scotland to the show to discuss his work in molecular complexity leading to his development of the Molecular Assembly index to help search for biomarkers and life on other planets.  Our co-host was avid Space Show listener and supporter, Bill Gowan.  You have probably heard Bill's questions as he has been a frequent listener and participant in our program in recent years.  After the start of the program, I introduced Bill as the co-host and Bill introduced us to Dr. Cronin as he had been in communications with him re his molecular work for some time. 

Lee described his work as trying to understand how chemistry turns into biology, using robotics to do chemistry and drug discovery, and to understand the physics of life.  After the introductions, I asked Lee to describe and explain his work in chemistry referred to as molecular complexity.  This led him to talk about the “maker” tools they are putting together in the lab to assemble molecules and create a search engine. He responded to the question “What is life?” with an unconventional answer. Briefly, he described living systems as objects with memory with memory that have causal power. Be sure to hear him explain what this means, including the role of evolution and purpose.  Lee went into some detail about “assembly theory” which is the basis for the Molecular Assembly Index, or MA figure that is applied to molecules. (See the Nature paper posted on the blog.) 

Our guest received several questions asking him about evidence and is this or that living.  For example, he said a virus was definitely living. Bill asked whether the Covid 19 virus and its variations were proof.  Don't miss how he explained this.  I asked if Earth as a planet was alive.  He said yes but went on to say that the solar systems contains life but is not living.  He talked about sub species and even the theory of having agency meaning we can act in a way that is good or bad.  Before moving on, I asked if his MA could detect life other than carbon-based life.  Don't miss how he answered this one along with the input on the question offered by Bill.

In response to an email question, Dr. Cronin clarified that the MA index can be used with molecular data coming from spectrometry from advanced telescopes (maybe from JWST) and from mass spectrometers that are sent on robotic missions. Be sure to hear the discussion about which missions have sensitive enough spectrometers and why. Lee’s answers to other questions addressed the likelihood of life elsewhere in the solar system and planetary protection.

The subject of searching for life on Mars came up as Bill asked for Lee’s thoughts about Dr. Levin's Viking Labeled Release experiments.  This led me to ask our guest why NASA has yet to launch a dedicated life searching mission.  I found it interesting that Lee suggested the answer might lie in politics and that it was more of a political issue and concern than a technical or actual potential mission question.

Fremont John called to clarify whether the index can be used to find life-as-we-don’t-know-it and how that works. He also asked what the MA index would be for DNA. Lee stated that the MA for a single set of A-T-C-G molecules would be around 35. Tim sent an email asking about the MA and the Drake Equation, Panspermia, and Desert Varnish as a form of life in our biosphere.  A few minutes later, Tim sent in the last email for the day asking about the lowest value for molecular complexity that would be produced by life.  Lee answered all the questions before we ended the program.

Please submit all questions/comments to the blog for this show.  You can reach Dr. Cronin through me, the blog or his university faculty website page.  Bill Gowan can be reached through me or by posting on the blog. 






Dr. Cronin in Scotland will discuss his work on Molecular Complexity. Mr. Gowan is our co-host.

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17 Dec 2021 Dr. Lee Cronin
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