 The show 's theme song , " The Ballad of Serenity " , was written by Joss Whedon and performed by Sonny Rhodes . Whedon wrote the song before the series was greenlit and a preliminary recording performed by Whedon can be found on the DVD release . The soundtrack to the series was released on CD on November 8 , 2005 , by Varèse Sarabande , although a 40 @-@ minute soundtrack was released by Fox Music in September 2005 as a digital EP . " The Ballad of Serenity " was used by NASA as the wake @-@ up song for astronaut Robert L. Behnken and the other crewmembers of STS @-@ 130 on February 12 , 2010 . 
