The Colonization Application
Season 8, Episode 17 - Aired March 5, 2015

As Sheldon and Amy choose to buy a pet turtle, Amy is angered to learn that Sheldon has applied for a one-way mission to colonize Mars. Meanwhile, Leonard and Penny take a step forward in the bedroom when Leonard makes an adult purchase, while Raj worries about Emily's reaction when she finds out he's been snooping in her apartment.