Previous Carnegie recipients of the Medal include Carnegie president Maxine Singer (1992), DTM staff member Vera Rubin (1993), Observatories staff member Allan Sandage (1970), former president, director, and staff member (and now trustee) Philip Abelson (1987), trustee Frank Press (1994), former Genetics Department staff member Barbara McClintock (1970), and former Carnegie president Vannevar Bush (1963).
Wetherill is known for a variety of scientific achievements. In the 1950s, he was among a group of Carnegie scientists who developed geochemical methods involving natural radioactive decay to date the Earth's rocks. Later, his interests in age-dating techniques expanded to include extraterrestrial materials, including meteorites and lunar samples. In the 1970s, he began theoretical explorations into the origins of meteorites and the terrestrial planets, developing a technique to calculate numerically the orbital evolution and accumulation of planetesimal swarms.
In addition to showing how the inner solar system formed, this work led to a model of a giant- impact origin for the Moon and the core of Mercury.
Wetherill joined DTM in 1953 as a member of the scientific staff. He left in 1960 to become a professor at the University of California at Los Angeles, and, in 1975, he returned to Carnegie as DTM director. He stepped down in 1991 and now serves again as a staff member. He is widely known as an individual of great integrity and creativity.
The Carnegie Institution of Washington is a nonprofit science research and educational organization founded in 1902 by Andrew Carnegie. It is led by Maxine F. Singer. The Department of Terrestrial Magnetism, led by its director, Sean C. Solomon, is one of Carnegie's five operating centers.