Broadcast 3292 Dr. Christopher Morrison

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Guest:  Dr. Christopher Morrison;  Topics:  Space nuclear propulsion and related nuclear energy issues and concerns. 

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We welcomed back Dr. Chris Morrison to a one segment 122 minute discussion regarding space nuclear propulsion, nuclear power issues, technical concerns and more. We started our detailed, comprehensive, and often technical discussion with Chris by reading an advance email we got from BJohn in Sweden.  Here is the questions which I repeat here since it has turned into a short back and forth blog exchange with BJohn and me: 

"I'd like to hear if there are any news about the Russian development of a nuclear proposed cruise missile, and if there are any other known projects like that.

I wonder what limits there are to managing the effect of nuclear electric output. In our Earthly power grids, nuclear power plants are used as base power, delivering a fairly constant amount of electric effect. Regulating the effect quickly is done by hydroelectric and carbon burning electric plants. Is this somehow inherent to nuclear power? And is it a significant limitation for space needs, where there are no regulating power plants around?

Would nuclear electric power be useful to suddenly for a short time power up a laser or microwave beam to propel a sailing spacecraft, such as investigated by the Breakthrough Starshot Initiative of Yuri Milner?"

Chris responded to all of the questions asked by BJohn.  My blog exchange with him was limited to my comments about BJohn asking multiple guests, including the same guests, the same question multiple times as if he was looking for a certain answer and would not stop asking the question until he got the answer he wanted.  If this interests you, please read our exchange on TSS blog for this program.   Otherwise, I am quite sure you will find what Chris had to say in reply to BJohn's questions to be of interest.

Our guest moved on and talked about the recently approved NASA budget which had $100 million earmarked for thermal nuclear propulsion research with a demo by 2024.  We talked about this research and project in some detail and fielded a few listener email questions.  Part of the discussion was technical including an ISP discussion along with the use of low yield enriched uranium.  One of the questions that came up was that since the nuclear rocket would not be turned on until after launch, the listener wanted to know how it got to orbit and on what type of rocket.  The answer was on an upperstage for the SLS and maybe down the road a commercial rocket.  Chris had much to say about this including his explaining the safety to us both while on the pad and during launch and in nuclear safe LEO's.  He also talked about uses which might include lunar tugs, Mars vehicles and more.  Before moving on, Chris was asked about the total cost to operation.  He estimated $600 million to get the demo going.  He also said probably close to or about a billion dollars for operation.  Referring back to the BJohn question, Chris commented on DARPA's and the Defense industry interests nuclear power, mainly because it becomes very easy to harden and protect nuclear power components.  Don't miss what our guest had to say on this subject.

Marshall was our first caller. He talked about the ITR Tokamak fusion reactor but Chris said it was not really for propulsion.  Listen to the explanation for this.  HE3 was mentioned and we learned that Neptune has tons of HE3. Chris brought up LEU.  Don't miss the Marshall call.

Chris next moved us to new items on his company blog.  He said UltraSafe now had a functioning website. Visit it at  He updated us on the company Micro Modular Reactor and their bid activity for nuclear power in the Canadian Artic.  Chris once again explained their reactor and the Canadian effort, plus we talked some about the competition in the field.

Next, we received multiple email questions from Bruce from Canada.  His first question focused on asking our guest why NASA could not be a better administrator to help create nuclear employment and innovation.  In addition, Bruce asked about NASA Kilopower.  Later, his second question focused on how one gets Isp 900 thrust with a current LEU project using low yield U235.  Chris explained this to Bruce so listen carefully as technology was involved in the answer. 

John Hunt from Ft. Worth was our second caller.  He talked abut cooling, including the use of water.  Our guest talked about legacy hardware and reactors but said new reactors don't have the same issues, problems or limitations as the older reactors.  Don't miss this detailed and interesting discussion.  VASIMIR came up as did other nuclear technologies and cooling concepts.  Bruce sent in another question asking about "helium gas being used as a coolant sink in space for a hot U235 reactor core.  Space is at Absolute Zero there is plenty of coolant there."  Don't miss what Chris said in response to his question which was a good one.

Freemont John called to ask about the regulatory environment and if it was discussed at the conference Chris attended last month.  Chris had much to say about the regulatory environment, interest in modernizing it via the OSTP,  plus he talked about fission safety on the ground and in LEO nuclear safe orbits.  The conference mentioned was the Nuclear and Emerging Technologies for Space (NETS) 2019.  You can learn more by reading this Forbes summary at  While on the topic, we also discussed using nuclear propulsion to launch from the ground.  Chris talked about it and explained why it cannot be done at this time.  He then talked about how USNC was being reorganized with a special space division,  Don't miss what he said about his work and the new company division.

Other topics that came up included water as a nuclear fuel, tungsten, and an accurate timeline for operational nuclear propulsion.  One topic getting lots of attention was the radiation medical research done with rodents with high doses of radiation over very short periods of time.  Chris explained why he believed these wee faulty experiments.  Make sure you listen to all of what he said regarding the use of labs, the cost involved and why the research model needs to be changed.  I told him that he was missing the medical side of the argument and suggested he interview the people having done some of the better known radiation experiments on rodents.  I offered him introductions to those that had been on the show and will be doing that over the next few days.  I also offered to have both Chris and the researchers on a show together talking about how this research is done, especially if there were better ways of doing it without financial and logistical constraints on the researchers.  There will be a follow up on this subject so stay tuned for more. 

Chris offered closing comments and a few elaborations on earlier comments.  Don't miss what he had to say as we closed the program for today.  Be sure to asked your questions and leave your comments on TSS blog for this show.  You can reach Chris through me or the websites referenced above.




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31 Mar 2019 Dr. Christopher Morrison
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