The Smurfs #7: The AstrosmurfPaperback, 2 August 2011

When Smurf wants to travel to outer space, he tries to build a rocketship, but it fails to get off the ground and he grows depressed. Papa Smurf and the other Smurfs make a plan to cheer him up: putting him to sleep and waking him up in an elaborately staged "planet" filled by other Smurfs pretending to be aliens!