Guest: Les Johnson. Topics: solar sail, space propulsion, interstellar space travel, environmental organizations. Les Johnson was our guest for this program for our discussion of solar sail technology and deployment, interstellar space travel and propulsion ideas, and the space advocacy community relationship with environmental organizations. Our first segment focused on solar sail technology and the efforts so far to have a successful solar sail demonstration flight. Les described the size of the sail needed, the challenges, the material for the sail, and the formulas that support the solar sail theory. We also talked about scientific and commercial uses for solar sail propulsion, its usefulness in space and the limits of its usefulness which appear to be at Jupiter. In explaining the solar sail, we talked about light with momentum and pushing and why we cannot experience it here on Earth but how it’s proven in the vacuum chambers and in space. During the second segment, we spoke about his new book which will be out in early fall, "Paradise Regained: The Re-greening of Planet Earth," which explains why space advocates and environmentalist have so much in common and should be working together. This resulted in a very interesting and diverse conversation with good listener questions and comments. You won't want to miss it! During our final segment, we focused on the out-of-the-box aspects of interstellar propulsion. Among the technologies that may be useful are solar/laser sails, fusion, antimatter, and maybe folding space with worm holes. However, all of these are beyond current engineering, physics, and financial means. This is also a most interesting reality based discussion that you will want to hear. Toward the end of the program, we talked about careers in out-of-the-box physics, what academic subjects or fields to pursue and more. If you want to send a question or comment to Les Johnson, you can do so at http://www.lesjohnsonauthor.com/contact_les or les.mail@lesjohnsonauthor.com . Visit his website at http://www.lesjohnsonauthor.com/ .