It is most famous for its use in Stanley Kubrick's 1968 film 2001: A Space Odyssey, and its 1984 sequel, Peter Hyams' 2010: The Year We Make Contact.

The text (in Latin) is from the Roman Catholic Requiem Mass: Lux aeterna luceat eis, Domine, cum sanctis tuis in aeternum, quia pius es.

The piece features many of Ligeti's characteristic styles, including: The piece can be seen as divided into three distinct parts, as designated by text: Lux aeterna luceat eis [m.1–36]: The sopranos and altos sing very similar parts in Ligeti's characteristic style of micropolyphony.

Domine cum sanctis tuis in aeternum... [m.37–86]: The basses enter, singing in very high falsetto, showing Ligeti's focus on timbre and texture.

It is characteristic of nearly all Ligeti's mature works that the subdivisions of the basic beat keep changing, which contributes to their beatless, floating feeling.