Broadcast 2962, Dr. John Jurist, Dr. Jim Logan

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Guests:  Dr. John Jurist, Dr. Jim Logan:  Topics:  Human medical factors for spaceflight, radiation, microgravity & 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 both Dr. John Jurist and Dr. Jim Logan back to the show to update us on the latest developments with human factors research for long duration human spaceflight, lunar and Mars outposts, space settlement and more.  Early in the program our website went down and several listeners could not hear the show. We were about to stop the program one hour into our discussion when the website returned to life so we kept going for two hours 8 minutes without a break.  Note that Dr. Logan started us off by telling us about a JAXA-NASA mouse experiment using a rodent centrifuge on the ISS.  Jim explained this experiment and the findings released to date which he said were very important. Also, Jim noted it was the first time ever such an experiment had been done.  He said he had talked about this type of research many times over the years as we need to develop the gravity prescription for humans.  Listen first to Dr. Logan describe the experiment and the results and what they mean.  Dr. Jurist then provided us with his insights and both doctors suggested what should be done next.  While there was not enough data to really extrapolate, both doctors seemed to think that both the lunar gravity and Mars gravity would only be marginally different from zero gravity.  Listen to what they had to say about this experiment, the findings released to date,  plus their complete analysis.  Don't miss it.

We had multiple emails and callers.  Another topic we discussed was the risk of cardiovascular disease in space. Specifically, I asked about the incidence of heart disease for Apollo astronauts compared to the general population.  Listen to what Dr. Logan had to say about this, small sample sizes and what we know and don't know.  Dr. Jurist also weighed in on this subject.  You might be surprised at what they said about cardiovascular issues in space so don't t miss this discussion.

The next topic was talking about what we do know about Mars radiation from various instruments on the way to Mars, in orbit over Mars and on the Martian surface.  Radiation was a big issue for the rest of the show so do pay attention.  Adrian sent in many questions taking issue with much of what the guests said.  The realities of shielding were discussed as well as quantities needed. The idea of having 100% Earth equivalent shielding at the space destination was discussed though Dr. Doug suggested other options in his email.  Don't miss how Jim responded to him.

We took two phone calls from John in Redding about gravity and more.  He also put forth one of his theories on his second call to the show.  As a result of our radiation discussion, Adrian pointed out that different people on Earth have different radiation tolerances.  We talked about that, gene modification, using Crisper for gene editing and more.  We talked about timelines for new technology to enter the field.  I suggested long time lines given what I hear from people delivering healthcare and technology to end users.  Jim and John had more to say about this and Adrian sent in additional emails which I read on air. 

Doug wanted to know about radiation levels and asked about using lower levels since not all places on Earth were equal, citing the work done by Al Globus for an Earth LEO space station in a low radiation orbit.  Jim had much to say about this and protection levels, including why he used 100% Earth level radiation per Earth's atmosphere.  Don't miss the exchange and discussion with Dr. Doug on these issues.  Dr. Jurist then added some additional factors concerning gene splicing and editing with Crisper and technology. 

Another topic introduced by our guests focused on the unintentional consequences of some of the new technology and the unknowns.  Our guests talked about this subject which generated some blowback from Adrian as you will hear from his emails. 

Jim wanted to talk about definitions and said we needed to carefully define terms.  Don't miss this important discussion about the meaning of sorties, outposts, frontiers, settlements, and more.  This discussion also related to the multiple comments our guests and listeners made earlier in the show about children and babies in space, having babies in space and living at a space settlement.  Our guests explained why the baby/children aspect was very risky and unethical, especially since a baby or a child cannot consent.  At one point, I think out of frustration, Jim suggested a radiation experiment that could be done on humans right here on Earth.  Of course it would be unethical but that was part of the point Jim was making regarding full body scan CTs every few days for a year or more to see the radiation effect.  But back to definitions, listen to how he defined these different types of missions.  Both Jim and John later said that they thought all lunar and Mars missions would be outpost missions.  Let us know what you think about this with your blog comments. 

Near the end of the show, I asked our guests about other human factors given there were about 37 issues for humans in space.  They said if you got rid of microgravity and radiation, you would probably get rid of 32 or so of the 37 as they lead to other conditions and are the big ones to work on.  Jim also said the others were focused on physical isolation which explained as part of this discussion.  Don't miss what he said about isolation.

Before the show ended, we took additional emails from Adrian, then John and Jim said the gap between engineers and medical types still existed and was a problem.  Jim left us with a closing comment that expressed his cynical attitude toward NASA and the space community having squandered opportunities for decades.  Don't miss Jim's concluding statement for our program today.

Please post your comments/questions on TSS blog.  You can reach either guest through me. We apologize for the website problems and any difficulties this may have caused you tuning into the show.  I have no explanation for why the website went down but I will be contacting our hosting company for an explanation.  Tu guard against problems like this happening in the future. I suggest you save the streaming URLs so you can access them without needing to go through the website.




Human factors and space medicine updates

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06 Aug 2017 Dr. John Jurist, Dr. Jim Logan
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