Recorded on November 16, 1965 at RLA Sound Studios New York City.
Side A is labeled as Side B.
Early repress, maybe as well from 1966. Side B has a Sun Ra portrait.

Some mono copies were issued in stereo covers.

156 Fifth Avenue, NY NY 10010
MONO ?

Recorded on November 16, 1965.

Per the Omniverse book, there are three mixes of side A. This edition's mix has background vocals audible throughout "The Sun Myth." The other mixes have them much quieter or completely removed.

156 Fifth Avenue, NY NY 10010
MONO ?

156 Fifth Avenue, NY NY 10010
MONO

156 Fifth Avenue, NY NY 10010
MONO

Recorded on November 16, 1965 at RLA Sound Studios New York City.
Side A "The Sun Myth" was recut with a different mono mix than the first issue.
Some mono issues came in Stereo sleeves.
Record Labels incorrectly state Sides A and B. Back of Cover correctly states track listing:
Side A: The Sun Myth
Side B: A House of Beauty, Cosmic Chaos

Plastylite "P" stamp on side 2

Recorded on November 16, 1965 at RLA Sound Studios New York City.
The this pressing notes the "156 Fifth Avenue" address on the back cover.
Side A is mislabeled as Side B and Side B as Side A but track listing is correct.

156 Fifth Avenue, NY NY 10010
STEREO

This repress has the centre labels without the deep groove like an otherwise similar repress (The Heliocentric Worlds Of Sun Ra, Volume 2), but the sleeve with the "156 Fifth Avenue" address on the backside like the original pressing (The Heliocentric Worlds Of Sun Ra, Volume 2).

Back cover reads:
All compositions by Sun Ra © 1966 United International (ASCAP)
Recorded on November 16, 1965 at RLA Sound Studios New York City
"There" [poem]
by Sun Ra © 1966

156 Fifth Avenue, NY NY 10010
STEREO

Recorded on November 16, 1965 at RLA Sound Studios New York City.
The original pressing (this) notes the "156 Fifth Avenue" address on the back cover. There is also a repress which notes "300 W. 55 Street" as the address.
Sides are not labeled, but have the same B&W image of Sun Ra.
The back cover does not have the standard picture of Sun Ra, but rather has ESP releases as in the 1966 record sleeve.
The Sun Myth track is the B version that has no background vocals.
My understanding is that the 156 Fifth Ave cover changed in 1970, so this definitely 1969 at the latest. That it is the B version of Sun Myth and is in stereo indicates it is likely not 1966, but either '67 or '68.
There is a mono version of this listed, this is the stereo version.
Max runout is simply 1017A / 1017B

300 W. 55, NY NY 10019
STEREO

1970 Pressing with "300 W. 55 Street" as the address. Purple and white picture label on side 1, black label on side 2.

Copies came with folded "Garden of Delights" poster insert.

Runouts identical to Version 3: Sun Ra - The Heliocentric Worlds Of Sun Ra, Volume 2.

"Although the Vol. 2 in the title insinuates some degree of continuity with its predecessor, this is a bit of a misnomer as the only acknowledged connection with The Heliocentric Worlds of Sun Ra, Vol. 1 (the volume number only indicating the order in which they were issued). Due in part to the wider exposure and distribution of the ESP label, enthusiasts and critics were unanimous in their recognition of this masterpiece of free jazz -- or, as Ra called it, "space jazz."

The Heliocentric Worlds of Sun Ra, Vol. 2 is comprised of three unique compositions: "The Sun Myth," "A House of Beauty," and "Cosmic Chaos." Sun Ra's work with an ensemble often presents a stated emphasis on the percussive nature of solos as well as within the group context. The underlying freeform anti-structure allows defining contrasts that ultimately establish the progressing sonic sculpture. "The Sun Myth" showcases Ra's definitive capabilities to guide his assembled musicians from anywhere within said group. He is heard on this recording initiating improvisational exchanges on tuned bongos -- for a portion of the track -- rather than from his customary keyboards. The resulting interactions include mesmerizing bass solos from Ronnie Boykins as well as some impassioned alto sax work from Marshall Allen. Directly contrasting the works that surround it is "A House of Beauty." The emphasis shifts, juxtaposing Allen's unfettered piccolo solos with Ra on piano and Robert Cumming on bass clarinet. Of particular note here are Ra's achingly lyrical piano runs and chord progressions, which weave between the light percussion beds and the dominant woodwind section. "Cosmic Chaos" is the final and most archetypal of the ensemble works that Ra and his various Arkestras would produce throughout the '60s. The extended piece begins with rush upon rush of aggressive counterpoint, building into unreserved group crescendos that are likewise punctuated by various woodwind soloists."