Broadcast 2873 Hotel Mars Dr. David Grinspoon

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Guests: John Batchelor, Dr. David Grinspoon, Dr. David Livingston.  Topics:  Trappist-1, Proxima B, exoplanets, interstellar flight.  You are invited to comment, ask questions, and discuss the Space Show program/guest(s) on the Space Show blog. Comments, questions, and any discussion must be relevant and applicable to Space Show programming. Written Transcripts of Space Show programs are not permitted without prior written consent from The Space Show (even if for personal use) & are a violation of the Space Show copyright. We do not permit the commercial use of any Space Show program or part thereof, nor do we permit Space Show programs to be edited, placed on YouTube, or other private channels & websites. Space Show programs can be quoted in news articles, papers, academic & research work but must be cited or referenced in the proper citation format. Contact Dr. Livingston for questions about our copyright and trademark policies which we do enforce.  This program is archived on The Space Show website, podcasting, and blog sites with permission from John Batchelor. Please visit the John Batchelor Show website for more information about this fine program,  Remember, your Amazon Purchases Can Help Support The Space Show/OGLF ( note that audio and transition issues are a result of copying the John Batchelor broadcast & are not within my control as they originate in the Batchelor studio.

John Batchelor and I welcomed back Dr. David Grinspoon to discuss the recent discovery of the Trappist-1 exoplanet system consisting of seven planets, Proxima B, exoplanet atmospheres and finding life on them, interstellar flight and more.  We started our discussion with Trappist-1 and the luck in finding a system where the planets line up just right so that when they pass in front of their sun, they get backlighting and this enables us to understand the mix in their atmosphere which is key to searching for life.  We talked about the tools needed for this type of analysis which mostly revolve around new generations of telescopes. 

Other topics in our double segment discussion included Proxima B which was discovered using a different method so we cannot easily determine the mix on the Proxima B atmosphere.  We also talked about the range of gravity on Proxima B as compared to Earth.

John asked Dr. Greenspoon questions about people making the interstellar flights plus he asked about the Breakthrough Starshot project.  Other topics for both Trappist-1 and Proxima B were discussed in this Hotel Mars program.

You can email Mr. Batchelor or Dr. Greenspoon through me.  David's website is





Exoplanets and interstellar flight with Dr. Grinspoon

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01 Mar 2017 John Batchelor, Dr. David Livingston, Dr. David Grinspoon
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