FINDING NEW WAYS TO COPE WITH SPACE DEBRIS-OR RISK IMPRISONING OURSELVES ON PLANET EARTH? by Tom Logsdon

For the past 58 years, starting in 1957, mankind has been launching enormous swarms of satellites and useless space debris in the vicinity of planet Earth. Many of these fragments swoop around our home planet at 17,000 miles per hour. When they collide at such high speeds, huge numbers of space debris fragments are instantly created many of which continue to circle around the Earth with the possibility of further collisions. In the 1978 Donald Kessler, a talented researcher at NASA Houston, realized that successive collisions could create ever larger swarms of debris fragments that could, in turn, engage in further collisions to create even more dangerous fragments. Soon the space around the Earth would be swarming with dangerous, high-speed metallic shrapnel. This phenomenon has, in the meantime, then called the “Kessler Syndrome”. It is similar in concept to the nuclear chain reactions that make atomic bombs possible. Donald Kessler made careful estimates of the total tonnage of large objects in Earth orbit that could end up imprisoning us on our beautiful, blue planet. Flying space missions through swarms of high-speed debris could become much too dangerous for anyone to advocate. Separate studies have indicated that a highly energetic collision at a speed of about five miles per second (typical for low-altitude impacts) could create as many as 20 objects per pound of mass involved in the collision. What can be done to minimize the probability of a runaway “Kessler Syndrome” that could, theoretically, imprison all of us on planet Earth? 1. We could impose more stringent rules on the launching satellites and the debris fragments that typically result from such a launch. Some rules have already been established in conjunction with space exploration. These could be made more stringent. And they could be accompanied by fines or other penalties for those who fail to comply. 2. We could remove existing debris fragments from space to minimize the hazard of collisions. Some experts envision roving capture devices (e. g., spaceborne drones) that would rendezvous with — and remove — useless debris fragments from their orbits and hurl them back to Earth into remote oceans areas for safe disposal. 3. Ground-based lasers could illuminate selected debris fragments to push them out of orbit. Serious studies of this approach have been conducted at NASA headquarters, at NASA Houston, and at the Kirtland Air Force Base in Albuquerque, New Mexico. 4. Large debris fragments could be tracked with precision with ground-based and space-based sensors to pin down their trajectories to a high degree of accuracy. Probable collisions could then be predicted and spaceborne devices could be launched to nudge one or both of the objects onto safe collision-free trajectories. Among other approaches, puffs of air have been proposed to accomplish this goal. In 1978 Donald Kessler managed to develop a highly imaginative concept now called the Kessler Syndrome. His analysis indicated that, if we continue on our present path, we could all become prisoners on planet Earth unable to engage in the safe exploration of outer space. Fortunately, techniques are available to help mitigate this worrisome hazard. Tom Logsdon, who penned this account, tells the story of the space debris fragments now enveloping planet Earth in his special short course: “ORBITAL AND LAUNCH MECHANICS” which is being sponsored by the Applied Technology Institute on January 25 – 28, 2016, in Albuquerque, New Mexico and on March 1 – 4, 2016, in Columbia, Maryland These courses, which are lavishly illustrated with 400 full-color visuals, also include detailed explanations of the counterintuitive nature of powered flight maneuvers together with explanations of the new “Superhighways in Space”, and the contrasting philosophies of Russian and American booster rocket design. The illustrative calculations included in the course all employ realworld data values gleaned from the instructor’s professional experiences in the aerospace industry. Each student will receive a full-color version of every chart that appears on the screen, several pamphlets and written explanations of the concepts under review, and autographed copies of two of Logsdon’s published books. A few slots are still available in those two classes. Register early to assure your acceptance.