ProjeKct X was the alter ego of the 2000 version of King Crimson - Robert Fripp, Adrian Belew, Trey Gunn, and Pat Mastelotto. While the "name" version of the band was composing and recording The ConstruKction Of Light (2000), they were also fooling around in the studio, improvising and having fun.
The fun, which one doesn't normally associate with Crim, comes through on this album of improvisations, outtakes, and random sounds: though it has its Crimmishly heavy moments, it's generally lighter in tone and feel than any Crimson studio recording since the days of Lizard.
Heaven And Earth is in many ways the predecessor of the improvisations that would take up much of the bulk of the live CD Heavy ConstruKction. Many of these traKcs consist, as do most of the Heavy ConstruKction improvs, of a groove laid down by Mastelotto, over which Gunn, Fripp, and Belew lay down anything from mellow soundscaping to screeching elephantosities. Heaven And Earth is not, however, a straightforward document of "what happened in the studio;" it is highly produced by Mastelotto and his jamming partner Bill Munyon, with parts joined to form something like composed pieces, overlaid with various spoken words, strange sounds, and additional rhythm bits. The result is something that, strangely, you could dance to, if you were inclined to dance. (But then, the '00 Crim were actually a startlingly danceable band; Belew liked to inform the people on the floor that "You've just been dancing in 7/8 time.")
Some of the tracks are outright silly, such as "Two Awkward Moments; others are strangely beautiful - particularly the last three tracks, which strike wistful emotions quite unlike Crimson-as-Crimson, a band whose emotional range tends to start at tension and end at terror.
The ConstruKction Of Light represented, more than anything else, a new band attempting to create something new while coping with the King Crimson heritage. Heaven And Earth was, I think, the same band discarding that heritage - not completely, but enough that it could find its own unique voice and make its own definitive contribution to the Crimson heritage.
That contribution would come three years later, with the release of The Power to Believe. In the meanwhile, The ConstruKction of Light and Heaven And Earth are the record of two sides of a band that had not yet quite bleshed those sides into a single identity.