``Fifteen Years of Commercial Space in Retrospect''
21st Century Earth Observing Systems: Emerging Role for Spaceports
A Coherent Vision for Space Exploration and Development in the 21st Century
A Comparison of Alternative Methods for the Mars Sample Return Mission
A Concept for Robotic Lunar South Pole Exploration
A Concept of Driving on Orbital Station
Advanced Spacecraft Mechanisms Work at the USAF Research Laboratory
Aerodynamic Considerations for Rooftop Helideck Design
Air Force, NASA and Commercial Cooperation in Establishing a Robust Space Infrastructure
A lunar exploration architecture using lunar libration point one