The album was considered the "spiritual follow-up" to A Love Supreme. It features Coltrane and Pharoah Sanders as soloists, both playing tenor saxophones.

One of the few harpists in the history of jazz, Alice Coltrane recorded many albums as a bandleader, beginning in the late 1960s and early 1970s for Impulse! She is also known by her adopted Sanskrit name Turiyasangitananda.

Coltrane described Om as the "first syllable, the primal word, the word of power". Issued posthumously, the 29-minute recording begins and ends with Coltrane and other musicians chanting in unison.

In a contemporary review for Rolling Stone, music journalist Stephen Davis called Interstellar Space "plainly astounding" and found Ali to be the ideal complement for Coltrane's mystical ideas: "He outlandishly returns the unrelenting outpour of energy spewing from Trane, and the result is a two-man vulcanism in which Ali provides the subterranean rumblings through which the tenor explodes in showers of notes."