Named in memory of Harold D. Babcock (1882–1968) and in honor of his son Horace W. Babcock, astronomers at Mount Wilson Observatory, the latter also serving as director of Palomar Observatory. The elder Babcock’s precise laboratory studies of atomic spectra allowed others to identify the first “forbidden” lines in the laboratory and to discover the rare isotopes of oxygen. With C. E. St. John and others, he extended Rowland’s tables of the solar spectrum into the ultraviolet and infrared. The Babcocks ruled excellent large gratings, including those used in the coudé spectrographs of the 2.5-m and 5-m telescopes, and they measured the distribution of magnetic fields over the solar surface to unprecedented precision. The younger Babcock invented and built many astronomical instruments, including the solar magnetograph, microphotometers and automatic guiders. By combining his polarization analyzer with... _ _.