In today's Crash Course Astronomy, Phil takes a look at the explosive history of our cosmic backyard. We explore how we went from a giant ball of gas to the system of planets and other celestial objects we have today.

Today on Crash Course Astronomy, Phil dives into some very dark matters. The stuff we can actually observe in the universe isn’t all there is. Galaxies and other large structures in the universe are created and shifted by a force we detect mostly indirectly, by observing its impact: DARK MATTER.