Americanastronomer. He worked at the Mount Wilson (where he was employed originally as janitor) and Palomar Observatories. In the 1920s he participated in long-term projects with W. S. Adams, Alfred Harrison Joy (1882–1973), and others to measure the absolute magnitudes and radial velocities of thousands of stars. From 1930, first with the 100-inch (2.5-m) telescope and later the 200-inch (5-m), he measured the radial velocities of hundreds of faint galaxies, finding progressively larger redshifts.
Subjects: Astronomy and Astrophysics.