Join or Sign In
Sign in to customize your TV listings
By joining TV Guide, you agree to our Terms of Use and acknowledge the data practices in our Privacy Policy.
Earth's habitability and its significance in the universe is examined by physicists and astronomers, including Paul Davies and Robert Jastrow.
Loading. Please wait...
There are no TV airings over the next 14 days. Add it to your Watchlist to receive updates and availability notifications.