How the heck do we map out a planet without oceans? NASA had to figure that out when we sent the Mariner 9 probe to Mars. There's some tricky, yet fascinating science behind all of it! In this episode of Crash Course Physics, Shini talks to us about sea level, kinetic theory, and phase changes. -- Produced in collaboration with PBS Digital Studios: null -- Want to find Crash Course elsewhere on the internet? Facebook - http://www.facebook.com/YouTubeCrashC... Twitter - http://www.twitter.com/TheCrashCourse Tumblr - http://thecrashcourse.tumblr.com/ Support CrashCourse on Patreon: http://www.patreon.com/crashcourse CC Kids: null