Vera Rubin

Vera Rubin, a pioneering astrophysicist who confirmed the existence of dark matter, died Sunday, Dec. 25, 2016, according to multiple news reports. She was 88.

She was a retired staff astronomer at the Carnegie Institution’s department of terrestrial magnetism in Washington, D.C.

“Vera Rubin was a national treasure as an accomplished astronomer and a wonderful role model for young scientists,” said Carnegie president Matthew Scott. “We are very saddened by this loss.”

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According to the Carnegie website, in the 1960s, Rubin’s interest in how stars orbit their galactic centers led her and colleague Kent Ford to study the Andromeda galaxy, M31, a nearby spiral.

After observing more galaxies by the 1970s, Rubin and colleagues found that something other than the visible mass was responsible for the stars’ motions. Each spiral galaxy is embedded in a “halo” of dark matter — material that does not emit light and extends beyond the optical galaxy. They found it contains five to 10 times as much mass as the luminous galaxy. As a result of Rubin’s groundbreaking work, it has become apparent that more than 90 percent of the universe is composed of this invisible material.

According to the American Museum of Natural History’s website, Rubin was fascinated by stars at an early age. Her father helped her build a telescope. She graduated from Vassar College in astronomy and then attended Cornell University where she studied under the legendary physicist Richard Feynman. She received her doctorate in 1954 from Georgetown University and taught at the school for a decade.

Colleague Neta Bahcall of Princeton University said, “Vera was an amazing scientist and an amazing human being. A pioneering astronomer, the ‘mother' of flat rotation curves and dark-matter, a champion of women in science, a mentor and role model to generations of astronomers.”

According to National Geographic magazine, Rubin was a powerful advocate for the equality of women in astronomy. She would call conference organizers and point out their lack of diverse speakers. She fought for women to be accepted at Washington’s exclusive Cosmos Club.

She was elected to the National Academy of Sciences in 1981. She was the first woman to receive the Royal Astronomical Society’s gold medal since Caroline Herschel in 1828, and she was awarded the National Medal of Science in 1993.