One Down, 51 to Go

One Down, 51 to Go is an achievement in Halo: Reach. It is unlocked by completing a Weekly Challenge.

Trivia

 * The name comes from the number of weeks in the year which is 52. Completing one weekly challenge represents the completion of 1 out of 52 challenges.
 * The name references to one of Johnson's quotes in Firefight: "One down, 50 Billion to Go".