Unit 10: Dark Matter
Since Swiss astrophysicist Fritz Zwicky first inferred its existence in 1933, dark matter has remained one of the greatest unsolved mysteries in cosmology. Invisible to telescopes, dark matter was detected through its effects on visible matter. Astronomical measurements have shown that dark matter is three-fourths of all matter, but at present no one has yet directly observed a dark matter particle. See how astrophysicists are seeking evidence for dark matter at the center of the Milky Way galaxy and how a new detector almost a mile underground will look for dark matter particles in the laboratory.