The compositional credits go to Jon Anderson, Chris Squire, and Bill Bruford, though keyboardist Rick Wakeman contributed some uncredited sections.
The song itself ends very abruptly around 10:35, but a reprise of "We Have Heaven" from earlier on the album is included as a hidden track, extending it to 11:27 (11:32 on the 2003 release).
Original North American pressings of Fragile contain the reprise, but list "Heart of the Sunrise"'s timing as 10:34, not reflecting its inclusion.
Rick Wakeman contributed to the writing of "Heart of the Sunrise" (and fellow album piece "South Side of the Sky") by adding piano interludes to both songs, but was not credited because of contractual conflicts.
"[4] Yes drummer Bill Bruford claimed that "the band hit its real template" with the song, commenting on its "drama" and "poise".
In the early part of the Big Generator tour, the main riff was worked into an instrumental version of "Almost Like Love", which led off the show.
Progressive metal band Dream Theater paid tribute to Yes with a live cover of this song, which is included on their Uncovered 2003-2005 official bootleg.