Guest: Les Johnson. Topics: "Going Interstellar: Build Starships Now!," and interstellar propulsion & advanced propulsion concepts. You are invited to comment, ask questions, and discuss the Space Show program/guest(s) on the Space Show blog, http://thespaceshow.wordpress.com. Comments, questions, and any discussion must be relevant and applicable to Space Show programming. Transcripts of Space Show programs are not permitted without prior written consent from The Space Show (even if for personal use) & are a violation of the Space Show copyright. We started our discussion by talking about interstellar travel, his new book, "Going Interstellar," and advanced concepts, both for NASA and outside the NASA mindset. Please remember that if you purchase this book from Amazon using this link, Amazon will make a contribution to The Space Show/OGLF: www.amazon.com/Going-Interstellar-Johnson/dp/1451637780/ref=onegiantlea20. Les told us that both he and his co-editor, Jack McDevitt, had very little trouble getting the authors to contribute to the book which consists of a series of short stories from well known science fiction authors plus scientists. There is a focus on the plausible and grounded physics so that the sci-fi is rooted in actual physics. Les took several phone calls wanting to know about advanced concepts and propulsion at NASA and in general outside of NASA. We spoke about many concepts including solar sail technology, nuclear electric propulsion, the fission fragment rocket, faster than light (FTL) travel, antimatter, & the types of possible starships that might be used, plus the time intervals to travel from point A to point B. We talked about the challenges from the laws of physics, political leadership, funding, & timelines. Les said that barring the discovery of new physics which he is not optimistic about at this time, he does not think FTL travel will be possible. When I asked about the discovery of Higgs-boson as an example of discovering new things, he talked about the discovery of that which is predictive as compared to something entirely new and unknown. Other topics in this segment included artistic license in sci-fi writing, the role of physics & the imagination, & even questioning the possible role of ET in contributing to advanced propulsion concepts. In our second segment, Marshall was our first caller & we talked about the French nuclear program, fusion, & the large ITER reactor program. Les went over many of the fusion energy challenges & we talked about some fuel issues. Les then told us about some of the future books he is working on & then he had more to say about solar sail technology which is his preference at this time for robotic interstellar missions. We took a call about the huge Atlanta, GA sci-fi conference, DragonCon ( http://dragoncon.org) as Les will be a featured speaker there this year. As the program was ending, we talked about HSF NASA infrastructure, the Von Braun model for spaceflight, and more about the specific stories in his book. If you have questions/comments for our guest, please post them on The Space Show blog. Check out his websites at www.lesjohnsonauthor.com and www.amazon.com/Les-Johnson/e/B002OUOYZQ/ref=onegiantlea20.