Gernot M. R. Winkler
Gernot Maria Rudolph Winkler (October 17, 1922 – April 30, 2016) was responsible for the Time Service Department of the United States Naval Observatory (USNO) from 1966 to 1996. Winkler oversaw the introduction of caesium beam-based Coordinated Universal Time based on hyperfine transitions and an internationally transportable "flying clock".