Vera Rubin

Young astronomer Vera Rubin was born in Pennsylvania, USA, in 1928. Fascinated by the night sky from an early age, she built her Rubin found evidence of the mysterious dark matter that affects how stars move within galaxies. The dark matter detective who proved that most of the Universe is INVISIBLE Did you know? In 1965, Rubin became the first woman to use the powerful telescopes at the Palomar Observatory, California, USA, for her research. Vera Rubin own telescope out of cardboard at the age of 14. Determined to pursue her passion, she studied ASTRONOMY – despite being told that it was an unsuitable career for a woman.

Puzzling discovery

Rubin studied spiral galaxies and discovered that their outer stars moved much faster than expected. Since most of a GALAXY’S MASS lies at its centre, she had expected the outer stars to move more slowly than the inner ones – just as the outer planets in our Solar System orbit the Sun more slowly than the inner planets.

This is because the pull of gravity weakens with distance.

Who came before…

In 1932, Dutch astronomer Jan Hendrik OOrt suggested the existence of invisible matter after discovering that the mass of the Milky Way must be greater than what could be detected visually. In 1934, Swiss astronomer Fritz zwicky discovered that the speed of galaxies in the Coma Cluster was faster than predicted. He concluded there must be matter that could not be seen, and called it dark matter.

By the way… When asked about my discovery on dark matter, I said, “I’m sorry we all know so little. But that’s kind of the fun, isn’t it?”

Rubin studied the Andromeda galaxy in particular because of how close it is to Earth.

Mysterious matter

Rubin’s calculations showed that these galaxies must contain a heavy, but invisible, ingredient – known as DARK MATTER – that holds them together. After further research, she concluded that spiral galaxies contain around 10 times more dark matter than visible matter – and therefore that most of the mass of the Universe is hidden from view.

Who came after…

Rubin used a spectrometer to view previously invisible starlight.

American astronomer W Kent Ford worked closely with Rubin on her dark matter theory. He developed an extremely sensitive spectrometer – an instrument that detects invisible light – for the research.

How she changed the world

Rubin’s discovery transformed astronomy, and while scientists still don’t know what dark matter is, they believe it accounts for about 95 per cent of the Universe, along with a mysterious force called dark energy.

Today, neta a Bahcall, a prominent astrophysicist and professor, investigates the formation of galaxies, the structure of the Universe, and how dark matter is distributed within it.