This work for 2 violins, viola and 2 cellos was originally commissioned as a string quartet by the Kuhmo Chamber Music Festival in 1997. According to Rautavaara, it nevertheless seemed to acquire a will of its own: it clearly demanded a second cello. The subtitle, Les cieux inconnus, is from a poem by Charles Baudelaire which the composer set for male choir in the 1970s. The motif from the song appears again in this music.