Broadcast 2286 (Special Edition)

22 Jul 2014 Dr. Mark Shelhamer
Your Amazon Purchases Helps Support TSS/OGLF (see

Feedback: What did you think of this show?: 

Guest: Dr. Mark Shelhamer. Topics: A look at the risks associated with long duration human spaceflight. Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, 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 For those listening to archives using and rating the programs, please email me as to why you assign a specific rating to the show. This will help me bring better programming to the audience. We welcomed Dr. Mark Shelhamer, Chief Scientist of the NASA Human Research Program to the show to discuss the critical risks associated with BLEO long duration HSP. You can hear his FISO talk on this topic from April 2, 2014 at His associated Power Point can be downloaded at During the first segment of our 95 minute discussion, Dr. Shelhamer started off saying we would be talking about beyond low earth orbit only and that many of the risks are unknown since we have very little experience with BLEO. Much of what we do know is extrapolated from our current knowledge base plus our Apollo experience. Next, our guest defined three major areas/issues. First he listed medical issues which he later described as onsite medical treatments for various complications, illnesses, surgical needs and such. He classified physical deconditioning issues such as muscle and bone loss issues, cardio vascular issues in a different category. The second group he identified had to do with radiation, and the third group included psychological-social issues. I asked about Microgravity not being in the top three and he said because those issues are likely a constant for both LEO and BLEO missions. He then talked at length about the challenges needing countermeasures/mitigation. He did not say these were showstopper challenges but they do require effective countermeasures. For example, he said humans could probably survive a trip to Mars today providing the hardware & life support was up to the job but their goal is to get the crew there in good condition, to be able to do effective work, and to return safely. He did not think those goals could be obtained today. I asked if money was a primary issue and it was not though he said more money is always helpful. He talked about the time needed for some human studies, team studies, and research, sometimes extending even longer than a year. He then took us through the three categories to tell us what NASA was doing & how it was doing in that research area. You might be surprised by what you hear. I certainly was. Later, we talked about ocular/vision issues which are now getting front page attention. He explained the latest theory causing the problem as possible fluid shifts. Listen to this discussion. Note that once we start with BLEO HSF, we may find other problems that do not now show up now. Also, we may develop a countermeasure for one problem but that opens the door to lots of other problems currently unknown. One tool he talked about that was being tested on the ISS Russian sector was lower body negative pressure. Artificial gravity was a big part of our discussion. While everyone is enthusiastic about it, he made the point of saying we don't know the needed spin rate nor do we know what level of gravity is needed for humans or for how long. Just spinning a spacecraft without knowing this information is unlikely to be successful let alone cost effective or economic. He also pointed out that artificial gravity is costly, requires lots of energy, a huge spacecraft which means lots of mass to orbit, & to do it, it needs to be done in a way that maximizes the benefits for the crew. Without knowing the precise spin rate and gravity needs for humans plus how long the crew needs to be in artificial gravity, it is likely it won't be done just for cost and economic reasons alone. Charles emailed in about bed rest analog studies. Joe sent in a question about lower back pain & spine issues. As the segment ended, I asked him if humans were lousy candidates for BLEO spaceflight. Don't miss his answer. In the second segment, we took a call from Dave about nuclear submarines as an analog for HSF studies. Our next topic was space radiation which our guest discussed in detail. I then took two email questions from B John in Sweden. He asked about the benefits of microgravity for disabled folks, then I read a longer email from him suggesting solutions for the microgravity, psychology, and radiation issues already existed and why was NASA not proposing and developing "these simple non-medical solutions to the problems you describe." Dr. Shelhamer responded to his email item by item. For the most part, he agreed with what B John was saying except that his information and perspective were limited and missing key components of the scenarios he was talking about. Mark explained why our listener's comments were way too simple and cited some scenarios to illustrate this. It was a fascinating reply to what many of us believe are already effective countermeasures. Unfortunately, while what many of us suggest is correct, what we suggest does not go far enough and does not contain the specifics and details of what is actually required to make a specific countermeasure work. Otherwise, the countermeasures are far more complex than what B John asked about in his email which you will hear me read on the program. I asked Mark about genetic modification and that took us to the subject of personalized countermeasures. We talked about pioneering/space settlement, childbirth & children in the space environment, even gender differences for BELO HSF. I asked about the differences from his perspective of doing HSF to the Moon, an asteroid, Mars, or Deimos. There are differences, don't miss his response. As the program was ending, I asked if a commercial company without gov. funding could decide to do a BLEO mission without all the costs and safety concerns of NASA. Mark said it might be possible though the costs of the missions and the technology needed would make it very hard for a commercial company to carry out. He said a short cut bare bones mission might be achieved by a commercial company but the risks for the crew would be extreme. If you were running a commercial company and funding such a mission, would you accept these risks, plus the risk the crew might not be able to do much or be effective once they got to their destination? As the commercial company CEO, would that be a good use of company money or would you dismiss what people like our guest today have to say about these issues. Let me know your thoughts by posting them on the blog. Please post comments/questions on TSS blog above. Mark can be reached through me or through his PPT presentation address.



WARNING: Using Disqus Comments on the Space Show:

To ensure your comments do NOT get caught in the Disqus automatic spam filter systemplease login to your Disqus account or create a verified/approved Disqus account.

Posting multiple URL links WILL TRIGGER the Disqus automatic spam filter system.