GETTY/EPA Famed astronomer Vera Rubin has passed away, her son has confirmed

The US astronomer who pioneered work on invisible dark matter in the universe, and who some colleagues felt was overlooked for a Nobel Prize, died on Sunday. She had suffered dementia for several years and was at an assisted living facility in Princeton, New Jersey, Allan Rubin, a geosciences professor at Princeton University, said in an email. Rubin, a Philadelphia native, used galaxies' rotations to discover the first direct evidence of dark matter in the 1970s while working at the Carnegie Institution in Washington.

GETTY Rubin was the first to discover direct evidence of dark matter

Working with spectrograph designer Kent Ford, Rubin found that material at galaxies' edges rotated at the same rate as material in the centre. The discovery contradicted a law of physics that said the greater mass in the centre, such as dust, stars and gas, meant it should move faster than the edge, where there was less mass.

If dark matter doesn't fit that description, I don't know what does Emily Levesque, University of Washington

The explanation was a halo of dark matter around the galaxies that spread mass throughout the galaxies. Dark matter has not been directly observed but has been inferred through work by Rubin and other astronomers and physicists. Scientists have discovered that a small part of dark matter is made of neutrinos - tiny, fast-moving particles that do not really interact with regular matter. Emily Levesque, an astronomer at the University of Washington, told Astronomy Magazine in June that Rubin deserved the Nobel Prize since the discovery of dark matter had revolutionised astronomy and the concept of the universe.

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EPA She received a National Medal of Science from Bill Clinton in 1993