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Goddard Space Flight Center, Greenbelt, Maryland 20771

ENGINEERING COLLOQUIUM

Monday, December 10, 2007 / 3:30 PM, Building 3 Auditorium

Tom Thompson

"The Transit Story: How Tracking Sputnik Gave Birth to Modern Navigation "

ABSTRACT -- Modern satellite navigation techniques evolved from an experiment William Guier and George Wiffenback at Johns Hopkins University Applied Physics Laboratory (JHU/APL) conducted on the telemetry signals form the Sputnik I satellite in 1957. They discovered that the Doppler signal data received from a signal pass provided sufficient information to determine the Sputnik I orbit parameters. They soon deduced that the reverse calculation revealed the location of the ground site and proposed this technique to the Navy for tracking submarine locations . Similar methodology is the basis for the GPS navigation system we use today. Tommy Thompson of JHU/APL, one of the original members of the JHU/APL team, will tell this amazing story behind modern space exploration.

SPEAKER -- Tommy Thompson's career began at the dawn of the space age. After spending 5 years in the Navy, Tommy earned an electrical engineering degree from Lafayette College with the GI bill. He came to Johns Hopkins University Applied Physics Laboratory (JHU/APL) in 1960 to work on the Terrier Missile program. In the early sixties, Tommy was as a Radio Frequency (RF) engineer designing transmitters with these quirky new devices called transistors. These transmitters soon became part of more complex systems that eventually became powerful navigation tools for Navy submarines and their missiles. His career reflects the benefit that DOD's strategic programs have had on civilian space endeavors as well as the unique role JHU/APL has played, because it was home to both early rocket experiments and the search for the solutions to the difficult problems of submarine missile navigation. Tommy was involved with many of APL's significant contributions to DOD's navigation and communications systems, from the DODGE (DOD Gravity Experiment) Program to validation and testing of the now operational GPS system. The Transit Story is the result of this merger of expertise in both early space experiments and difficult navigation problems. 




Engineering Colloquium home page: https://ecolloq.gsfc.nasa.gov