Broadcast 2896 Dr. John Hunter

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Guest:  Dr. John Hunter;  Topics:  Green Launch hydrogen gas gun and DNA to space.  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 Dr. John Hunter to the program to update us with his work on the Green Launch hydrogen gas gun testing program about to start at the Yuma Proving Grounds (YPG).  He also talked about his plans to send DNA to space.  Our program was 90 minutes but in one segment as there was no break.  As with all John Hunter programs, our guest tends to ramble and go off the "topic reservation" so to speak and I typically go down that path with him.  Thus, you will hear us talk about nostalgia TV programs with his TV friend producer who is ill, the infamous Yuma Prison, his dog toy company, HurriK9, plus a few other topics that made it to the airways such as former Gov. Arnold Schwarzenegger.  That said, John always returned to topic and we came away with the latest news on the Green Launch hydrogen gas gun project.


John told us about his project financing through a Kickstarter program ( plus financing from friends and family.  He said the horizontal testing program would commence Monday at the YPG with the expectation of starting vertical testing later this summer.  In addition, he explained the part of the project pertaining to sending DNA to the Karman line.  Dr. Hunter provided the technical specs for the launch testing program, then we started talking about the payloads suitable for the gas gun.

John explained the Mini-Mart payload concept which you can read about at their Kickstarter site above.  He noted that for now these were all suborbital flights.  He then said there would be a scientific payload to sample the CO2 in the atmosphere on the way up.  He explained this module and how it would work in some detail.

Several listeners sent in email questions plus John took a few calls from listeners.  Listener George asked him about possible commercial interest in his project.  In reply, Dr. Hunter explained why it was challenging to get commercial and investor interest in a space project before it was actually demonstrated.  Thus, he said that the interest would come after they had successfully demonstrated their technology and project.  Don't miss all of what he said on this as it applies to all startup space projects, not just Green Launch.  Another set of listener questions asked about possible launch rates once the Green Launch project enters the operational stage.  Another listener asked him about his gas gun experience with the lab so John talked in general about space guns (hydrogen gas guns for launching cargo).  He referenced his former HARP program and told why it was eventually discontinued.

Listener John from Ft. Worth called.  His first question was about the possibility of using the gas gun as a weapon.  While John said it was possible, he said it was not practical.  You want to hear all of what he said on this subject but in summary, the gas gun does not make a good weapon because it does not salvo very well which is something you want as a feature of an advanced weapon delivery system.  Our guest then took us off topic to remind us of the Dr. Gerald Bull story and gas gun development.  If you are not familiar with the Bull story search for Dr. Gerald Bull and supergun or anything like that and you will find more than enough information to satisfy your curiosity.  Here is one decent article for you,  Dr. Hunter followed the Dr. Bull story, telling Ft. Worth John about achieving orbit with a launched payload using the gas gun.  He explained why the orbit needed to be circularized, he explained the Delta-V and much more.  Optimum payloads were mentioned including the use of some optical payloads. 

Rob called to talk about the business of scaling up the Green Launch project.  John explained how nicely it scaled up, listing the performance characteristics as you increased the size of the gun.  I asked him if it made any difference if the gun was placed at a higher altitude.  Don't miss what he said about this.  In brief, his answer was no.

Listener Bob asked him if this particular launcher could resupply either a lunar or Mars settlement.  As for Mars, would it need to obey the laws of physics and pay attention to Mars launch windows?  John said it obeys the same laws of physics as everything else does.  He said it was perfect for resupplying space settlements.  I gave him a timeline question and he said he wanted to do the vertical shot testing and flights this year.

Eric was our last caller saying he wanted to see gas gun launches from the surface of Mars to various places throughout the solar system.  Dr. Hunter liked that idea.  I questions Eric about his ideas for Mars.  He believes the Musk and SpaceX plans will materialize and both Eric and John said that Must and SpaceX would be at Mars before NASA. 

Several times during our conversation, Dr. Hunter talked about the barrels of oil needed to take one person to and from Mars.  He had much to say about this issue, suggesting this was a primary reason why NASA had never seriously entertained humans to Mars.  When you break down the energy costs to Mars per person the way John did throughout this program, you begin to see just how costly such a launch would end up being. 

Please post your comments/questions on TSS blog for this program.  You can reach Dr. Hunter through his websites or me.  Check out the Leonard David article about the project at




Green launch, DNA to the Karman Line

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11 Apr 2017 Dr. John Hunter
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