Introduction to Orbital Perturbations

Professor James Longuski has authored or co-authored over 250 conference and journal papers in the area of astrodynamics on topics that include designing spacecraft trajectories to explore the Solar System and a new idea to test Einstein's General Theory of Relativity. He also coauthored several papers with Dr. Buzz Aldrin on a human Earth-to-Mars transportation system known as the "Aldrin Cycler."He has published three books: Advice to Rocket Scientists: A Career Survival Guide for Scientists and Engineers (2004, AIAA), The Seven Secrets of How to Think Like a Rocket Scientist (2007, Springer), and Optimal Control with Aerospace Applications with José J. Guzmán, and John E. Prussing (2014, Springer). In 2008 Dr. Longuski was inducted into Purdue University's Book of Great Teachers.
Dr. George E. Pollock IV is the associate director of the Astrodynamics Department at The Aerospace Corporation. He leads a team of analysts providingspace domain awareness and advanced space mission analyses for the U.S. Space Force, Intelligence Community, and NASA customers. In over a decade of professional engineering practice, Pollock has directly contributed to national security space through innovative mission design, system concept analysis, and architecture studies. Pollock was a member of a team recognized with The Aerospace Corporation's Innovation Award in 2019. He has twice received Systems Engineering Division Awards for leadership and technical contributions to cislunar space analysis (2017 and 2019), and he was a member of a team that was recognized for Outstanding Contributions to Space-Based Space Surveillance and Space Situational Awareness (2012). The Space and Missile Systems Center's Space Superiority Systems Directorate honored Pollock as the FFRDC representative of the quarter in December 2014. He received Purdue University's highest award for graduate student educators in 2010. Pollock holds a bachelor's degree in aeronautical and astronautical engineering, a master's degree in aeronautics and astronautics, and a doctoral degree in aeronautical and astronautical engineering, all from Purdue University.
Felix Hoots has over 45 years of experience in space surveillance. Prior to joining Aerospace, he worked as an astrodynamicist for the 14th AF and NORAD/ADCOM and then as a Chief Scientist for GRC International. His work as a contractor supported the Air Force and Navy as well as the intelligence community in their space and surveillance activities. He has had 20 publications in international professional journals including two commissioned encyclopedia articles and seven proceedings. He is a coauthor (with George Chao) of Applied Orbit Perturbation and Maintenance. He has been an invited speaker at NATO and International Astronomical Union conferences and was technical organizer and speaker at a series of US/Russian Space Surveillance Workshops beginning in 1994 and continuing until 2012. Hoots earned a bachelor's degree in physics and a master's degree in mathematics from Tennessee Technological University. He earned a PhD in mathematics with an emphasis in astrodynamics from Auburn University. Hoots is a Fellow of the American Astronautical Society and an Associate Fellow of the American Institute of Aeronautics and Astronautics. He has previously served as an Associate Editor of the AIAA Journal of Guidance, Control, and Dynamics. In 2006 he received the American Association for the Advancement of Science Award for International Scientific Cooperation. In 2016 he received the Brouwer Award from the American Astronautical Society and the Corporate Innovation Award from the Aerospace Corporation.