"Lux Æterna" (Latin for "eternal light") is a song by American heavy metal band Metallica, released on November 28, 2022, as the lead single from their eleventh studio album, 72 Seasons (2023).

[3] The song reached number 1 on the Billboard Mainstream Rock Airplay chart for 11 consecutive weeks, tied with their cover of Bob Seger's "Turn the Page".

[7] The music video, directed by Tim Saccenti, was first filmed on November 3, 2022, and features the band playing live on a stage.

Writing for Musictalkers, Nicholas Gaudet described the vocals during the chorus as "astonishing" as well as praising the outro and guitar solo.

Gaudet also interpreted the song as a retrospective look back on their career, calling it the best thing they have done in two decades.