Explore the mysterious realm of dark matter in this 32-minute lecture from the series "The Evidence for Modern Physics: How We Know What We Know." Delve into the fascinating concept that only 5% of the universe consists of known matter, while the remaining 95% is composed of dark matter and dark energy. Discover how scientists detect, measure, and account for these elusive components. Learn about Fritz Zwicky's coining of the term "dark matter," Vera Rubin's groundbreaking observations, and the role of gravitational lensing in understanding this phenomenon. Examine possible explanations for dark matter, including modified Newtonian equations, and explore how theories are tested. Prepare for an enlightening journey into the weird and wonderful world of outer space physics.