Vera Florence Cooper Rubin (/ˈruːbɪn/; July 23, 1928 – December 25, 2016) was an American astronomer who pioneered work on galaxy rotation rates.

[1][2] She uncovered the discrepancy between the predicted and observed angular motion of galaxies by studying galactic rotation curves.

[1] The Coopers moved to Washington, D.C., in 1938,[1] where ten-year-old Vera developed an interest in astronomy while watching the stars from her window.

[11] Rubin's older sister, Ruth Cooper Burg, was an attorney who later worked as an administrative law judge in the United States Department of Defense.

[5][10][14] She worked with astronomer Martha Carpenter on galactic dynamics, and studied under Philip Morrison, Hans Bethe, and Richard Feynman.

[17] Her dissertation, completed in 1954, concluded that galaxies clumped together, rather than being randomly distributed through the universe, a controversial idea not pursued by others for two decades.

From 1955 to 1965 she worked at Georgetown University as a research associate astronomer, lecturer (1959–1962), and finally, assistant professor of astronomy (1962–1965).

In 1963, Rubin began a year-long collaboration with Geoffrey and Margaret Burbidge, during which she made her first observations of the rotation of galaxies while using the McDonald Observatory's 82-inch telescope.

[10] During her work at the Carnegie Institution, Rubin applied to observe at the Palomar Observatory in 1965, despite the fact that the building did not have facilities for women.

[22] This image intensifier allowed resolving the spectra of astronomical objects that were previously too dim for spectral analysis.

[10][12] Wishing to avoid controversial areas of astronomy, including quasars and galactic motion, Rubin began to study the rotation and outer reaches of galaxies, an interest sparked by her collaboration with the Burbidges.

She observed flat rotation curves: the outermost components of the galaxy were moving as quickly as those close to the center.

[26][5][10] Rubin's calculations showed that galaxies must contain at least five to ten times more mass than can be observed directly based on the light emitted by ordinary matter.

As of 2024, the extremely agile telescope is in place and full operation is expected within the next year[39] When Rubin was elected to the National Academy of Science, she became the second woman astronomer in its ranks, after her colleague Margaret Burbidge.

[10] Rubin never won the Nobel Prize, though physicists such as Lisa Randall and Emily Levesque have argued that this was an oversight.

[12][40] She was described by Sandra Faber and Neta Bahcall as one of the astronomers who paved the way for other women in the field, as a "guiding light" for those who wished to have families and careers in astronomy.

[50] The Stuff Between the Stars: How Vera Rubin Discovered Most of the Universe is a children's book by Sandra Nickel and Aimee Sicuro.

[10] Motivated by her own battle to gain credibility as a woman in a field that was dominated by male astronomers, Rubin encouraged girls interested in investigating the universe to pursue their dreams.

[6][15][68] She, alongside Burbidge, advocated for more women to be elected to the National Academy of Sciences (NAS), selected for review panels, and represented in academic searches.

She said that despite her struggles with the NAS, she continued to be dissatisfied with the low number of women who were elected each year, and she further said it was "the saddest part of [her] life".