In our last episode, Dr. Katie Mack and John Green discuss what the ultimate fate of the universe might look like. 

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