Mysteries of the Cosmos

The Dark Side of the Universe Astronomers learn about the Universe by observing it with telescopes. But how much of the Universe can we actually see? We now believe that everything that we can see and feel, including gas, dust, stars, and galaxies only make up less than 5% of the Universe! The rest 25% is made of dark matter and the rest is dark energy.  In this lecture you will learn how astronomers actually figured out the existence of dark matter.

Program is free and open to the public.