Vera Rubin, Washington, DC; 16 October 2003

Vera Rubin 23 Jul 1928 - 25 Dec 2016

In the 1970s, Philadelphia-born astronomer Vera Rubin (1928-2016) made groundbreaking discoveries that provided the first convincing evidence of dark matter in the universe. Rubin and her colleague Kent Ford at the Carnegie Institution for Science's Department of Terrestrial Magnetism made a compelling observation: the orbital speed of stars in distant parts of galaxies did not abide by Newton's laws of gravity and was affected by something other than visible matter.

In 1993, Rubin received the National Medal of Science for this and other "significant contributions to the realization that the universe is more complex and more mysterious than had been imagined." She was also an ardent champion of women in science. An asteroid, a ridge in Mars's Gale crater, and the U.S. national observatory on Cerro Pachón in Chile have been named in Rubin's honor. The photographer Mariana Cook created this portrait for the 2005 publication Faces of Science.

Credit: National Portrait Gallery, Smithsonian Institution; this acquisition received support from the Smithsonian American Women's History Initiative Pool, administered by the Smithsonian American Women's History Museum