Robert Henry Kern (died June 4, 2015 in Danvers, Massachusetts) was an American engineer and entrepreneur who is known as the key developer responsible for designing and building the first operational space-borne cesium clock.
[1] He was also an internationally-recognized designer of cesium beam tubes and an innovator in the field of time and frequency.
In 1971, Kern founded the company Frequency and Time Systems and served as its president and general manager.
In 1978, he sold his interest in this company and in the following year founded Kernco in Danvers, Massachusetts, where he lived since 1960.
Kern held eight patents relating to atomic clocks and technology that made GPS feasible.