Dr. Lee Valentine returned to The Space Show for this program. We discussed many subjects including the Space Studies Institute (www.ssi.org), closed system environments for lunar and space settlements/habitats, asteroid deflection and planetary defense, to space investing with the entrepreneurial companies and other commercial space business ventures. Dr. Valentine spoke in some detail about planetary defense, the gravity tractor, and even the Planetary Defense Conference which will be held next year. We also spent a considerable amount of time on the first segment addressing closed environmental systems for the coming space habitats. During this program, Dr. Valentine expressed his optimism regarding the future of the private sector developing space resources and lowering launch costs and we both agreed upon the important contribution being made by the entrepreneurial companies, even those that in the end may not be successful in their ventures. You can contact Dr. Valentine with your comments or questions through me at drspace@thespaceshow.com or directly at info@ssi.org.