 In 1946, Cunningham followed Lehmer to Berkeley where the latter was a professor, joining the Department of Astronomy at the University of California, Berkeley (a department that had 10 members in 1964–1965), and at one point serving as the department's chair.With Lehmer, Cunningham planned the construction of the California Digital Computer (CALDIC).Working with the Leuschner Observatory in the 1950s and 1960s, Cunningham performed and published calculations of the orbits of comets.