1: A secretive way of saying "lets get high"
or offering to go get inebriated.
Dude1: "I wanna take a mission to mars and never come back"
Dude2: "I don't think we have enough stuff for that man"

or

Dude1: "I'm on a mission to mars right now!"
Dude2: "haha what'd you take?"
by Dread Panda May 4, 2009
Get the Mission to Mars mug.