Archive: Dark Matter, the mysterious substance in space

Dark Matter is a proposed form of matter that does not absorb, reflect or emit light. It is known to make up 27% of our universe, while the matter that makes up stars and galaxies accounts for only 5%.

In this archive episode, first released in March 2015, Melvyn Bragg and his guests discuss dark matter, the mysterious and invisible substance existing throughout the Universe. In 1932 the Dutch astronomer Jan Oort noticed that the speed at which galaxies moved was at odds with the amount of material they appeared to contain. He hypothesized that much of this 'missing' matter was simply invisible to telescopes.

Today astronomers and particle physicists are still fascinated by the search for dark matter and the question of what it is.

One leading theory is that Dark Matter is made up of WIMPS (Weakly Interacting Massive Particles) that are big, heavy and move slowly, interacting with gravity but not other particles.

Scientists have developed multiple theories about the make up of this substance, and they are able to test them through remarkable computer modelling that simulates the construction of the universe.

With

Carolin Crawford
Public Astronomer at the Institute of Astronomy, University of Cambridge and Gresham Professor of Astronomy

Carlos Frenk
Ogden Professor of Fundamental Physics and Director of the Institute for Computational Cosmology at Durham University

Anne Green
Reader in Physics at the University of Nottingham

Producer: Thomas Morris

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