Ep. 5: Black Holes

In this episode, John and Katie take a break from talking through the universe's timeline to focus on a mystery of our cosmos: black holes. Head to https://policygenius.com/crashcourse to get your free life insurance quotes and see how much you could save. This show is a production of Complexly. If you want to help keep Crash Course free for everyone, forever, you can join our community on Patreon at http://www.patreon.com/crashcourse See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.