−77.82X−78.29

−77.82X−78.29 (pronounced "negative seventy-seven point eight two by negative seventy-eight point two nine" ) is the second extended play and fourth release by South Korean girl group Everglow. It was released on September 21, 2020, by Yuehua Entertainment. It is available in two versions, −77.82X and −78.29, and contains four tracks, with "La Di Da" released as the lead single.

Title
The album is titled −77.82X−78.29 after the coordinates of Antarctica, which is featured on the album cover. During the showcase for the album, member E:U was asked about it; she explained, "All the albums we have released so far convey the 'Everglow universe'. It'll be quite fun putting together these clues about our story. I can't tell you everything yet, but the upcoming stories are equally enjoyable [...]".

Background
On September 7, 2020, Yuehua Entertainment revealed that Everglow would release their second mini-album titled −77.82X−78.29 on September 21.

Concept images came out between September 8–10. The tracklist was released on September 11, revealing four tracks: lead single "La Di Da", "Untouchable", "Gxxd Boy" and "No Good Reason"; the lyrics for "La Di Da" were co-written by member E:U.

The music video teaser for "La Di Da" was released on September 16, and the music video on September 21.

Composition
According to Yuehua Entertainment, −77.82X−78.29 represents Everglow's "powerful and intense charisma", as compared to their previous works. The album is characterized by its bolder sound.

The lead single, "La Di Da", falls in the uptempo electropop and retro categories, and its lyrical content is a "warning" to the "haters who are pretending and full of dissatisfaction in [this] confusing era".

Promotion
Everglow held a live showcase on September 21, where they performed "La Di Da" and "Untouchable".

The group started promoting "La Di Da" on September 24 at Mnet's M Countdown, followed by performances on KBS' Music Bank, MBC's Show! Music Core and SBS' Inkigayo.

They broke their first week's sales, with their album selling more than 25,000 copies.

Credits and personnel
Adapted from the album liner notes.

Musicians
 * Everglow – vocals, gang vocals (track 1)
 * Ollipop – drum programming (track 1), bass (track 1) , synthesizer programming (track 1) , keyboard (track 1)
 * David Anthony – drum programming (track 2), bass programming (track 2) , synthesizer programming (track 2) , keyboard (track 2)
 * David Amber – drum programming (track 3), bass programming (track 3) , synthesizer programming (track 3) , keyboard (track 3) , vocal arrangement (track 3)
 * Dan Glashausser – drum programming (track 3), bass programming (track 3) , synthesizer programming (track 3)
 * Lindgren – drum programming (track 4), bass (track 4) , synthesizer programming (track 4) , keyboard (track 4)
 * Storyboards – bass (track 4), synthesizer programming (track 4) , keyboard (track 4)
 * Tom Glashausser – guitar (track 3)
 * Hayley Aitken – vocal arrangement (track 1), gang vocals (track 1)
 * Anne Judith Wik – vocal arrangement (track 2)
 * Andy Love – vocal arrangement (track 3)
 * Rebecca King – vocal arrangement (track 3)
 * Melanie Fontana – vocal arrangement (track 4)
 * Jeon Jae-hee (Jarry Potter) – background vocals (tracks 1,4)
 * Sophia Pae – background vocals (track 2)
 * Choi Young-kyung – background vocals (track 3)

Technical
 * Ollipop – producer (track 1), digital editing (track 1)
 * David Anthony – producer (track 2)
 * David Amber – producer (track 3)
 * Glashausser (duo) – producer (track 3)
 * Lindgren – producer (track 4)
 * Storyboards – producer (track 4)
 * G-High – vocal directing (tracks 1,3,4)
 * Kim Sung-pil – vocal directing (track 2)
 * Kang Seon-young – recording (tracks 1,3,4), digital editing (tracks 1,3,4)
 * Min Sung-soo – recording (track 2)
 * Jang Woo-young – digital editing (track 2), mixing (track 2)
 * Michael "Lindgren" Schulz – digital editing (track 4)
 * Bob Horn – mixing (track 1)
 * Anchor (Prismfilter) – mixing (track 3)
 * Niera (Prismfilter) – mixing (track 3)
 * Jung Yoo-ra – mixing (track 4)
 * Kwon Nam-woo – mastering

Studios
 * Monotree Studio – recording (tracks 1,3,4), digital editing (tracks 1,3,4)
 * Doobdoob Studio – recording (track 2)
 * Björk Studios – digital editing (track 1)
 * MWF Hives – digital editing (track 2), mixing (track 2)
 * The One with the Big Bulb – digital editing (track 4)
 * The Echo Bar Recording Studios – mixing (track 1)
 * Prismfilter Mixlab – mixing (track 3)
 * 821 Sound – mastering

Publishing
 * The Kennel AB – original publishing (track 1)
 * The Key Artist Publishing – original publishing (tracks 1,2,4)
 * EKKO Music Rights Europe – original publishing (track 2)
 * Amberullo Publishing – original publishing (track 3)
 * Love to Pub Publishing – original publishing (track 3)
 * ThatGirl @17 – original publishing (track 3)
 * Danophonic Music – original publishing (track 3)
 * TGlass Music – original publishing (track 3)
 * Universal Music Publishing – original publishing (track 4)
 * Universal Music Publishing Korea – sub-publishing (track 1,4)
 * The Key Artist Agency – sub-publishing
 * Kobalt – sub-publishing (track 2)
 * Musikade – sub-publishing (track 3)
 * Warner Chappell Korea – sub-publishing (track 3)
 * MusicCube – sub-publishing (track 3)