An engineer who helped connect spacecraft operations with teaching about celestial mechanics. NASA identifies him as the author of the 2017 edition of Basics of Space Flight (2017 edition) by Dave Doody and as a flight-operations engineer for the Cassini mission. His navigation chapter explains how radio Doppler effect measurements constrain spacecraft velocity while signal travel times constrain distance, turning received radio signals into information for orbit determination.[ref]
Basics of Space Flight (2017 edition) by Dave Doody. Editorial page: authorship and flight-operations role
[ref] New to topics? Read the docs here!