Named in honor of Paul Helfenstein (b. 1954) of Cornell University, expert in solar-system photometry and developer of new techniques of extracting key photometric data about surfaces of minor planets from spacecraft observations. Helfenstein has been responsible for definitive analyses of Galileo's photometric observations of (951) Gaspra and (243) Ida and the NEAR data on (253) Mathilde and (433) Eros. Name suggested by B. E. Clark and citation provided by J. Veverka.