Broadcast 3476 Barry DiGregorio

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Guest:  Barry DiGregorio; Topics:  Barry's book "Discovery on Vera Rubin Ridge-Trace Fossils On Mars?, Mars sample return concerns, COVID-19 and more.


This program was dedicated to the memory of Dr. Jeff Bell.

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We welcomed back Barry DiGregorio to discuss his new book, "Discovery On Vera Rubin Ridge-Trace Fossils On Mars" plus Mars sample returns, COVID-19, and planetary protection due to possible microbial life on Mars microbes.  We started the program by asking Barry to introduce us to the topic and his book.  Barry told us how he stumbled on the Curiosity images that peaked his interest for trace fossils, then how he started to investigate because what he saw reminded him of trace fossils on Earth.  Barry provided facts and directions so that you too can find the same Curiosity images.  He talked about Martian sols and image numbers.  In his research, he was surprised to learn that the rover was actually rolled back to look at the "trace fossils" that it first seemed to overlook though NASA offers a different explanation for what Barry sees as trace fossils. Listen to what he said about NASA rolling back the rover and their explanation of what is shown in the photos..

During this discussion, Barry talked about the various Curiosity instruments that helped in the image and data collection.  He detailed many of the instruments and their contribution.  For example, he highlighted the ChemCam instrument.  In talking about the images, Barry was asked about trace fossils as compared to biological fossils that we seem to be more familiar with here on Earth.  He spent time describing trace fossils and how they come about.  It was an interesting discussion.  When you get his book you can clearly see the trace signatures in the photos Barry has in his book. 

A listener brought up a former Space Show guest claiming to have seen fossils in Mars photos.  Barry was asked why his work was different. Don't miss this discussion.  Barry moved along to talk about possible microbial life on Mars having been more advanced than life on Earth during the same time period.  We had quite the conversation on this topic including listener phone calls.  This is a discussion you don't want to miss.  We would certainly like to see your thoughts on this subject so post them on our blog.  Once again, Barry spent time describing his microbial life on Mars hypothesis regarding trace fossils.  He had callers on this subject asking him many interesting and detailed questions. 

At the end of the first segment, we started the discussion regarding planetary protection, a Mars sample return and the risk of bringing a possibly dangerous sample back to Earth. Barry used the current corona virus problem as an analog of what could happen if we brought back an untested and unscreened microbe that was very detrimental to Earth.  This conversation and risk was continued in the next segment.

In the second segment, Freemont John called to take us back to the microbial  life on Earth and Mars comparison initiated in the first segment.  John then morphed into the planetary protection argument.  Barry referenced the work of Dr. Carl Woese along with Dr. Cheryl Nickerson who is at Arizona State University.  Barry then continued pointing out the risks of bringing a sample return form Mars directly back to Earth. He thought it should be evaluated on the Gateway or some other orbital location.  Listeners challenged him.  The opinion of Dr. Zubrin was often used as a defense against what Barry was suggesting.  And of course, COVID-19 was the comparable point for this discussion. 

Later, a listener, in referencing Musk wanting to go to Mars with lots of people, asked Barry if he thought SpaceX could get a launch license without passing through planetary protection requirements.  The same for an EIR.  That question was not ever answered in any detail.   Barry then brought up the work of Dr. Gil Levin with his Viking experiments and said they suggested something, possibly microbial, might be in the Marian soil and it should be investigated before bringing it back to Earth.  He referenced Gil's work and experiment multiple times during our discussion.  Barry also referenced a somewhat recent Leonard David article on the subject:   "What can the coronavirus outbreak teach us about bringing Mars samples back to Earth?'  You can read it here:

As the program was about to end, we took a call from Tim in Huntsville who wanted to challenge Barry on his sample return ideas, again using the Zubrin arguments as to why it would be OK to bring the sample back to Earth.  Let us know what you think about this final Tim-Barry debate. 

Barry offered concluding comments plus he told us about his book being available on Amazon as an eBook.  He also said there were more than 200 documented Mars photos in the book.  Additional topics were introduced during the discussion by other callers, Marshall and Ft. Worth John,  plus those sending in emails.

Please post your comments/questions for Barry on our blog.  You can reach Barry though me at my Space Show address. 





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15 Mar 2020 Barry DiGregorio
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