akashic definition of: Zeta Body:

The Zeta Body is not in direct Spirit-to-Matter alignment with the 2nd Millennium (current) incarnated form, but is rather a 'double' of 1st / 3rd Millennium ( past and future realities) wave-creation. Wave-creation is a path that is created when two similar yet separate realities have occasion to 'touch,' or more appropriately to know one another. This forms a wave bending back on itself from both directions, meaning that it is bent by both realms of sentient consciousness. In this way, the dipole of an 'event' is created. A Zeta Body then, acts as an extension of the wave-creation, in this instance between the 1st and the 3rd Millennium (past and future). Somewhat like a time traveler, it can carry Light codes through the portal between the three realities, bringing a stronger coupling to the building charge of their shared wave-creation.

Usually, a Zeta Body arising from a 2nd Millennium incarnated form can only be sustained for a small period of linear time. In most cases, the consciousness of the individual is not even aware that such an activation has taken place, although he / she will certainly experience some 'sensation' of the event. Their Higher Self had in effect agreed to act as a transducer for the experience. Such occurrences happening for an individual unconsciously are rare, but it is even rarer particularly within the last 5 centuries, when an individual embodied within the 2nd Millennium (from Christ's crucifixion through current time) is consciously informed of this process. Yet this will come to pass with greater frequency as the world moves toward its appointment with the 3rd Millennium ascended reality (the New Earth Star).

Thoth explains the process involved whereby the Adonai Kodesh would 'cause' a current human to create a Zeta Body:

The command for this causation would come from that soul's 1st / 3rd Millennium beingness, thereby circumventing the fractured sub-system (2nd Millennium). However, the 2nd Millennium experiential role must out-picture a portion of the dynamic, for in doing so it projects itself into the true reality on some level of its multiple existence within the fallen condition. Understand that the 2nd Millennium experience is entirely the result of 1st Millennium consciousness attempting to bridge the gap into the 3rd Millennium.

(note: the application of the word "Millennium" is not in earth-time as we know it, but in earth reality zones of past-present-future.)