Drunvalo Melchizedek points out this larger sphere and the extension of the pranic tube in "The Ancient Secret of the Flower of Life, v. 2"

The outer Unity Sphere is stellated, with each tip being an access point for angelic guides. The inner surface of the Unity Sphere is white or silver in color, and has a large number of filaments leading to other geometric shapes within the aura. The outside of the Unity Sphere is golden, and can be turned a bright white in order to attract healing guides.

The Personal Sphere contains the first seven layers of the aura. It relates to our life here and now; this incarnation and physical body. The Unity Sphere includes all of our lives, and all of our connections with life and consciousness, including healing guides and angels from other lifetimes. As we expand our awareness beyond the Personal Sphere, we have access to alternative realities, potentialities, and possibilities.

The stellations of the Unity Sphere appear to come from a number of shapes, the dominant one in this usage being the icosahedron. This large icosahedron is a mirror for the smaller one, the Heart of Light, which sits within the Universal Heart. As the Heart of Light is tuned (to emotions, beliefs, or any frequency of intent), the large icosahedron resonates and is tuned in that same manner. In other words, what is in your heart is in your life.