Named in honor of Charles Elachi, assistant laboratory director for Space Science and Instruments, Jet Propulsion Observatory. His expertise is in radar sensing from space, including the successful Shuttle imaging radar experiments. He has particular interest in the assessment of the surfaces of the Earth and other planets, from the standpoints of both measurement (his Ph.D. is in electrical sciences) and interpretation (he also holds an advanced degree in geology). His accomplishments include almost 200 papers, two textbooks, numerous honors and participation in almost every radar survey from space since the early 1970s. (M 15428) _ _.