Named in honor of Jesse Greenstein (b. 1909), an expert in stellar spectroscopy with many discoveries concerning low-luminosity stars, white dwarfs, stellar chemical compositions and stellar evolution. In addition, Greenstein established and guided, during its first two decades, the astronomy department at the California Institute of Technology. As a statesman of science policy he was influential in the early history of radioastronomy in the United States, as well as in the early history of AURA. His friends and colleagues heartily endorse this naming. Citation prepared by J. Cohen.