Sandage, Allan Rex
Allan Rex Sandage, 1926–2010, American astronomer, b. Iowa City, Iowa, Ph.D. California Institute of Technology, 1953. He was a graduate student under Walter Baade and an assistant to Edwin Hubble. A member of the staff of the Carnegie Observatories from 1952 (emeritus from 1997), he continued Hubble's observational cosmology work after Hubble's death (1953) using the telescopes of Mt. Wilson and Palomar observatories and, much later, the Hubble Space Telescope. Sandage worked his entire career to determine the value of Hubble's constant (see Hubble's law), the expansion rate of the universe, making seminal contributions to dating the age of the universe and its stars and helping to win acceptance of the big-bang theory (see cosmology). He also discovered the existence of quasars and produced a three-dimensional atlas of the galaxies based on a survey that he led of the galaxies' red shifts.