Leland Erskin Cunningham (February 10, 1904, inWiscasset, Maine – May 31, 1989, inRichmond, California) was an Americanastronomer anddiscoverer of minor planets. In a career spanning 50 years, he became an authority on orbit theory and on precise measurements of the orbits of comets, planets, satellites, and space probes. He was also an early authority on electronic digital computers and assisted in their construction and use in orbit calculations.^[2]

Cunningham began his career as an assistant to astronomerFred Whipple atHarvard University. In this capacity, he became a driving force in using automated calculating methods for computing celestial orbits.

DuringWorld War II, Cunningham joined theBallistics Research Laboratory (BRL) atAberdeen Proving Ground inAberdeen, Maryland, putting his expertise in number crunching toward the war effort. The computational needs of the BRL revolved around the compilation ofartillery firing tables and bombing tables and employed a number of methods,human,analog, anddigital; the backlog of computation jobs was so overwhelming that a satellite computation center was opened at theUniversity of Pennsylvania'sMoore School of Electrical Engineering inPhiladelphia, and improved methods of automated computation were sought. Cunningham was present at the June 1943 meeting at whichJ. Presper Eckert,John Mauchly, and Lt.Herman Goldstine proposed the construction of theENIAC; the program was agreed upon the same day. Initial plans for the machine called for it to have a precision of 5 decimal digits, but Cunningham's input compelled the inventors to design it with a precision of 10 decimal digits.

From 1945 to 1946, Cunningham served on the BRL's Computations Committee atAberdeen Proving Grounds inMaryland, a group established as part of theBallistics Research Laboratory to prepare theENIAC for utilization following its completion the Moore School; the other Computations Committee members wereHaskell Curry,Derrick Henry Lehmer, andFranz Alt. His duties included supervision of the laboratory's shop ofIBM punched card calculating equipment, which was busy calculating ballistics trajectories, and writing sample problem specifications forbenchmarking the ENIAC.

In 1946, Cunningham followed Lehmer toBerkeley where the latter was a professor, joining the Department of Astronomy at theUniversity 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 theLeuschner Observatory in the 1950s and 1960s, Cunningham performed and published calculations of the orbits ofcomets. In particular, he showed thatComet Pereyra andComet Ikeya-Seki weresungrazers similar to comets seen in 1668, 1843, 1880, and 1882.

Cunningham died on May 31, 1989, at the age of 85. The minor planet1754 Cunningham was named in his honor.^[2]

• List of minor planet discoverers § L. E. Cunningham

• Cunningham on the site of the University of California
• Grosch, Herbert R.J. (1991).Computer: Bit Slices From a Life. Third Millennium Books.ISBN 978-0-88733-085-8.

• 1904 births
• 1989 deaths
• 20th-century American astronomers
• Discoverers of minor planets
• Discoveries by Leland E. Cunningham
• Harvard University staff
• People from Wiscasset, Maine

• Articles with short description
• Short description is different from Wikidata
• Use mdy dates from April 2018