Cosmology in recent decades has been undergoing a revolution. Astronomers have for the first time identified the major constituents of the universe, revealing a universe that hardly resembles what we thought only a few decades ago. It is filled with dark matter that is not visible and energy that permeates all of space, causing its expansion to speed up with time. Thousands of planets are now being discovered beyond our Solar System. New giant telescopes planned for the next decade are likely to reveal more surprises. In her lecture, Professor Freedman will describe these exciting advances.