Allan Rex Sandage
 (credit)

Born: 16 June 1926, Iowa City, IA

1975 Bruce Medalist
1991 Crafoord Prize

Education: University of Illinois; Ph.D. at the California Institute of Technology under Walter Baade.

Since 1952 Allan Sandage has been on the Research Staff at the Mt. Wilson and Palomar Observatories, (now The Observatories, a Pasadena, CA, facility maintained by the Carnegie Institution of Washington), where he began as a graduate student assistant to Edwin P. Hubble, the "father of observational cosmology." Dr. Sandage is now Astronomer Emeritus.

Following Hubble's death in 1953 Sandage continued with Hubble's passion to study the expansion of the universe. Periodically (with Gustav Tammann) he has updated the estimated value of the Hubble constant. Further, he has tried to establish a value for the deceleration parameter.

Seeking to determine the age of the oldest objects known, he has measured the ages and evolution of globular clusters. He has also calibrated  the "standard candles"  used to establish the distances of remote galaxies. As a result of his work in observational cosmology, the age of the universe has been measured progressively more accurately through the past decades.

Source: cosmiclight.com/tour/quasars.htmIn 1960, Dr. Allan Sandage made the first optical identification of a quasar, with his junior colleague, Thomas Matthews. He had found that there was a faint optical object with an extraordinary spectrum at the position of the compact radio source 3C 48 in the constellation Virgo. This faint quasi-stellar object was emitting more intense radio waves and ultraviolet radiation than a typical star.  (Following this discovery, in 1963, Maarten Schmidt explained the unusual spectrum as due to a huge red-shift of the hydrogen lines. This suggested the quasar was moving exceptionally fast (30,000 miles per second) and therefore was extremely distant (3 billion light-years away) and luminous as hundreds of galaxies.)

Subsequently Sandage has documented many more quasars, finding they are predominantly "radio-quiet" (99%).

Following research interests in stellar evolution, observational cosmology, quasars, and galaxy formation and evolution, Sandage has been prolific. He has published more than four hundred research papers,  is author of five books, with more activity as Associate Editor of the Annual Review of Astronomy and Astrophysics.

On September 25, 1991, he was presented a Crafoord Prize at the Royal Swedish Academy, This quadriennial award was established by the Swedish inventor, Holgerd Crafoord, to be astronomy's equivalent of a Nobel Prize.

RELATED LINKS:

A photo of Dr. Allan Sandage in front of the Mt. Wilson 100-inch telescope, the instrument first used to establish that the universe was expanding.

Biographies of Bruce Medalists, including Sandage as the 1975 award winner.

Congratulations on winning the Crafoord Prize from "Facts & Faith," First Quarter 1991 Issue.

Realm of the Quasar: Attractively illustrated coverage of the quasar and related topics of cosmology.



Additional reference: Larousse Dictionary of Scientists. Edited by Hazel Muir. Larousse, 1994.