"Celestica" is a song recorded by the Canadian electronic band Crystal Castles for their second studio album, Crystal Castles (2010). After a BBC Radio 1 premiere, it was released on April 16, 2010, as the first single from the album, being later accompanied by a music video. According to member Ethan Kath, the track was inspired by a suicide at the Celestica factories in Canada. Critics cited the song as a shift from Crystal Castles' usual sound, presenting a pop sound and resembling shoegaze. Others highlighted its melody and member Alice Glass' vocals. It was considered one of the best songs of the year by NME, while Pitchfork named it as one of the best tracks between 2010 and 2014 and among the best Crystal Castles songs.

Crystal Castles wrote "Celestica" for Crystal Castles (2010), which, according to a press release, was recorded at "an Icelandic church, a Canadian cabin, and a Detroit garage". According to member Ethan Kath, the track was inspired by a suicide at the Celestica factories in Canada, where a worker reportedly jumped into a vat of hot plastic, which was then rumored to be still used in manufacturing products.

Some critics described "Celestica" as a shift in Crystal Castles' usual glitchy and noisy sound; Molly Beauchemin of Pitchfork said that the song is "more muted" when compared to their other songs. Larry Fitzmaurice of Pitchfork compared it to Crystal Castles' "Courtship Dating" (2008), but with its "buzzy, brain-addling riff" replaced with "stadium-sized synths and a throbbing house heart". NME writers described the instrumental as a "Moloko-style anthemic pop house". Pitchfork's Ian Cohen and Jay Hill of Tiny Mix Tapes said that the track resembled shoegaze, with Hill comparing it to Galaxie 500 and Ride.

Multiple reviewers highlighted the melody of "Celestica"; Rebecca Schiller of NME described it as "sweepingly melodic", with Crystal Castles "embracing simple, calm beauty". She said that the song presents "spacious spirituality". Eric Torres wrote to Pitchfork that the track combines member Alice Glass' "gorgeous melody" with Kath's "cavernous synths and scraping guitars". DJ Zane Lowe of BBC Radio 1 described it as "deep club and longing melody", which was unusual for the band. The Guardian's Michael Hann compared "Celestica" to "those swooning, melancholy European faux-classical melodies" of Pet Shop Boys and described it as the most pop-centric of the Crystal Castles album.

Regarding Glass' vocals on "Celestica", Los Angeles Times writer August Brown described them as a delicate alto reminiscent of Hope Sandoval, while Emily Mackay of NME compared her soft singing to the one in Delerium's "Silence". The Quietus's Emily Bick compared them to Ladytron and Lady Gaga. Billboard staff said that Glass "glides sensitively", while Mosi Reeves of Spin wrote that she "coos seductively". Heather Phares wrote to AllMusic that the song "puts the focus on Glass' decidedly clear, melancholy vocals and the four-on-the-floor beat".

"Celestica" was premiered by BBC Radio 1 on April 15, 2010. It was digitally released as a single a day later through Polydor. A radio edit was released on May 31 through Fiction, Lies, and Last Gang in the United Kingdom. The song received remixes by Sonic Youth member Thurston Moore on June 2 and American band Bear in Heaven on June 9. A music video for "Celestica" was released on June 22, 2010. Directed by Ethan Kath and Rob Hawkins, the clip showcases children from the London College of Music playing violins and interacting in London's Abney Park Cemetery. At the same time, Alice Glass lip-syncs the song, while Ethan applies mud to his face.

Pitchfork's Larry Fitzmaurice named "Celestica" the "Best New Track" at the time of its release, describing it as "a stone-cold beauty of a song". Molly Beauchemin of the same website described it as an "excellent counterpart" to "Doe Deer", which follows "Celestica" on the Crystal Castles album, while also considering it a "gorgeous, harmonious classic". August Brown of Los Angeles Times described it as "fantastic" and "a delicate and unexpectedly moving single". It was named the 19th best track of 2010 by NME. In 2014, Pitchfork named it the 89th best track of the 2010–2014 period, and it was considered one of Crystal Castles' ten best songs until then by Beauchemin.

Digital single / EP

1. "Celestica" (album mix) – 3:50
2. "Insectica" (2004 version) – 1:48
3. "Seed" (2004 version) – 1:42
4. "Mother Knows Best" (2004 version) – 2:01
5. "Celestica" (single mix) – 3:47

Radio edit CD

1. "Celestica" (radio edit) – 3:34
2. "Celestica" (instrumental) – 3:50

Adapted from the radio edit liner notes.

• Ethan Kath – production, recording, engineering
• Paul Epworth – additional production
• Cenzo Townshend – mixing
• Nilesh Patel – mastering
• Alice Glass – vocals, lyrics