Thomas J. Ahrens

Thomas Julian Ahrens (April 25, 1936 – November 24, 2010) was an American geophysicist and professor at the Caltech. His research focused on the study of terrestrial planets and the impact processes on their surfaces. Ahrens completed his B.S. at the MIT in 1957, his M.S. at Caltech in 1958, and his Ph.D. at the Rensselaer Polytechnic Institute in 1962.

From 1958 to 1959, Ahrens worked as a geophysicist for the Pan American Petroleum Corporation. He served as a Second Lieutenant in the U.S. Army at the Ballistics Research Laboratory from 1959 to 1960. Ahrens then led the Geophysics Section at the Poulter Laboratory, Stanford Research Institute, from 1962 to 1967.

He joined Caltech as an Associate Professor of Geophysics in 1967, became a full Professor in 1976, and held the W. M. Keck Foundation Professor of Earth Sciences position from 1996 to 2001. He was named the Jones Professor from 2004 to 2005 and became a Jones Professor Emeritus from 2005 until his death in 2010.

Ahrens received several honors throughout his career, including the AAAS Newcomb Cleveland Prize in 1984 and election to the National Academy of Sciences in 1992. In 1996, he was awarded the Harry H. Hess Award. The iron-rich endmember of the γ-olivine solid solution series, γ-Fe2SiO4, was named "ahrensite" in his honor in 2013.