Lux Æterna (Metallica song)

"Lux Æterna" is a song by the American heavy metal band Metallica from their eleventh studio album, 72 Seasons (2023). It was surprise-released as the album's lead single on November 28, 2022. A thrash metal song described by James Hetfield as similar to the new wave of British heavy metal, the song is about the band's relationship with their fans, while the title means "eternal light" in Latin. A music video, directed by Tim Saccenti, was also released on the same day as the single.

"Lux Æterna" was met with a positive reception from critics upon release. It charted in several regions, including reaching number 1 on the Billboard Mainstream Rock and number 13 on the Bubbling Under Hot 100 charts in the United States. It was nominated for the Best Rock Performance award at the 66th Annual Grammy Awards, while the music video was nominated Best Rock Video award at the 2023 MTV Video Music Awards. It is the band's most performed song live from 72 Seasons, being played for the first time at their "Helping Hands" benefit concert in Los Angeles in December 2022 and later being played during their M72 World Tour.