Broadcast 2989 Barry DiGregorio

  • The Space Foundation Conference

  • The Space Foundation Conference

  • The Space Foundation Conference

  • The Space Foundation Conference

The Space Foundation Conference

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Guest:  Barry DiGregorio;  Topics:  Mars life detection, contamination issues, the color of Mars, Mars images and much more.  Please direct all comments and questions regarding specific Space Show programs & guest(s) to the Space Show blog which is part of archived program on our website,  Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See   

We welcomed back to the program Barry DiGregorio.  We started the first segment of our two segment 2 hour 6 minute program with Barry talking about the risks of contaminating Mars with human microbes, life, etc.  Our guest referenced the SpaceX timeline presented by Elon Musk a few days ago in his talk from the IAC in Australia.  Barry suggested a more plausible timeline would be in the 2030s.  This opened up a major discussion for today's program focusing on the possibility of human contamination of Mars or the risk of something unknown and dangerous to humans contaminating Earth assuming we might bring something risky back from Mars to Earth.  This what an interesting conversation with many "what if this or what if that" scenarios.  In addition, Barry referenced and mentioned The International Committee Against Mars Return (ICAMSR).  You can find out more about this organization by visiting their website,

The work of Dr. Gil Levin and his associate Dr. Pat Straat was referenced many times given the contamination and risk issues and the overall topic of planetary protection.  Many listeners do not concur with Barry's perspective and we heard from a few during this show.  We talked about the different scenarios, even SpaceX landing in the polar region where the cold my defer or prevent contamination toward the equatorial regions, a suggestion once made on The Space Show during a discussion with the NASA Planetary Protection Officer.  Barry said such a location would still be subject to wind and dust spreading spores.  He also referenced work which estimated it might take up to 100 years for contamination to impact multiple parts of Mars. 

Dr. Doug called in to talk about these issues, then later he emailed us as to a reason why NASA might not do life detection experiments on Mars.  This email came in when we had moved the discussion to talking about why NASA and others do not do life detection experiments for Mars.  One thought suggested that were life announced, it might prevent human exploration of Mars under the planetary protection policies.  Terry from Texas called in on this subject, suggesting a cover-up and conspiracy.  Both Barry and I engaged Terry on the subject.  Listen to what everyone said and post your thoughts on our blog.

Before the first segment ended, we talked about the idea of a Mars Sample Return coming back to Earth.  Here, we talked about containment technology and processes, off-Earth labs such as in orbit or on the Moon, specifically designed to do Mars sample analysis in a safe environment off Earth.  Barry reminded us of containment and quarantine issues during the Apollo 11 flight , plus he referenced what many astronauts and space professionals had said about these issues and some in interviews with Barry. 

We opened the second segment with Terry's call mentioned above.  Next, we switched the topic to Barry talking about the actual color of Mars which was not red.  Barry took us through a short history of how Mars got the red color, what early astronomers said about the color of Mars, then what happened when the Viking images started coming back to Earth for the first time.  The same for Hubble Space Telescope issues. Don't miss this part of our discussion.  Barry talked about the actual color of Mars and the Martian atmosphere and here is a hint:  The actual color of Mars is not red!  Listen to the full discussion on this issue.

We took a call from Don Davis, noted space artist.  You can check out Don's work at  Also on his site you can see many cool planetary photos and great photos and images of Mars.  Barry had one of Don's books available and they went over some of the photos Barry pointed out re the Martian color.  Don explained how color gets changed in publication, artistic license by publishers and other factors that may impact how a photo shows up in publication.  It was a good reality check on what see and may take for granted so don't miss it.  Don and Barry talked about the true color of Mars, various photos, how the images were acquired and much more.  This was a detailed discussion for most of the second segment.  Additional sites were reference such as the Pancam site (see 

Barry offered final comments and concluded by suggesting we visit the Planetary Society website for more Mars images.  You can check this out at The Bruce Murray Space Image Library at





Mars and so much more

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02 Oct 2017 Barry DiGregorio
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