Chanting the long version of the Gayatri consciously invokes energy from the 7 upper lokas into each of the chakras in ascending order.
(The short version only addresses the first 4 chakras). Gayatri bestows so many blessings it is difficult to know where to begin. Gayatri bestows a Kavacha (Spiritual/Divine Protection) to the practitioner.
Subtle Body Energies: The Seven Subtle Bodies
here are seven subtle bodies, or layers, around the physical body, which create the auric body system (aura). It is commonly said that these layers are like an onion, and that when you peel one away, you'll reach the next, but this is not true. As you extend inward, the one before is also present within the next aura layer. For example, the outer most body is the causal, or Ketheric body. The next is layer is the celestial body, which contains itself and the causal body. As you go inward, towards the first layer (the etheric) it will be the densest because it holds all seven subtle bodies. And of course, there is the physical body, which is the densest of them all.
The seven subtle bodies can be broken down as follows: There are three physical plane bodies, three spiritual plane bodies and the astral body, which is the bridge between the lower and higher bodies (some teachings claim that the astral is the fourth in the spiritual bodies). The lower three bodies process energies dealing with the physical plane, whereas the upper three process energies from the spiritual planes. Ịt is said that the energies from the higher planes must pass through the "fire of the heart" - the heart chakra-- to reach and be of full use by the lower bodies.
Each level of the aura has its own seven chakras, which are nested within the other auric chakras. As each layer extends outwards, the chakras vibrate at higher rates. So the seven chakras within the etheric body will be vibrating at a much lower frequency then the seven chakras within the causal body. So in actuality, the base chakra, for example, will have 7 major chakras, all vibrating at different frequencies. This way, energy can be transmuted between all bodies to all chakras.
First Layer (The Etheric Body)
This is the closest energy body to the physical. It is what is made evident through Kirlian photography. The etheric body extends one quarter to two inches beyond the physical body and pulsates at about 15-20 cycles per minute. The entire body, including organs, can be perceived but it is made of a bluish (emotional) or gray light (highly active).
Second Layer (The Emotional Body)
Since this is the emotional body, it is associated with feelings. It is more fluid in nature, and does not duplicate the body, as does the etheric body. This body is about one to three inches from the physical body. Unlike the etheric body, which is blue or grayish in nature, this is more like colored clouds that change color depending on what kind of emotions the person is going through. Love, joy, excitement, and even anger will result in very brilliant hues, whereas confused emotions will result in muddy tones. This body contains all the colors in the rainbow.
Third Layer (The Mental Body)
With an even more subtle composition, the mental body holds our thoughts and mental processes. It extends three to eight inches from the body, and generally has a yellow light, which radiates around the head and shoulders, and extends to the body below. This yellow will brighten if a person is deep in thought, or concentrating on mental activities. Although the color associated with this body is yellow, other colors are evident if there is an emotion associated with the thought (stemming from the emotional body).
Fourth Layer (The Astral level)
This is the true bridge to the spiritual plane! When we start to work with this plane, and above, our perception and abilities leap from the physical to the subtle. Here we will begin to perceive energies that are not of this vibrational frequency. The body of the astral is composed of gorgeous clouds of color, which extend six inches or one foot from the body. Not only does it have the same colors of the rainbow like the emotional body, but a pink, or rose hue is often present with these colors, especially if the person is a loving one. The astral plane is also called the "emotional" plane, which ties it strongly to the heart chakra and the second subtle body (the emotional body). Because it is so closely tied to the emotions, when people fall in love, great hues of pink can be seen shooting from their heart chakra. This is also why when we are in the astral, our emotions are greatly enhanced either way. When I am with my love in the astral, it is generally free of any lower body emotions, and our love is able to flow, without restriction.
The Fifth Layer (The Etheric Template Body)
This is what you would call a template for the lower template body (the first body referenced). This is the template that exists before the physical body is formed. Although this co-exists in a different dimension, it also extends one and one half to two feet from the body and can only be seen by clairvoyants and very advanced healers. This is an important layer in healing if the lower etheric body becomes disfigured as this is the true building block to the lower etheric. This template has a dark blue hue to it.
The Sixth Layer (The Celestial Body)
This is the spiritual emotional plane where a person will feel things such as bliss, and spiritual ecstasy. When we reach the place of divine love, interconnectedness (generally through deep meditation) we are touching on this plane, which is felt through our celestial body. When we raise our level of awareness, or consciousness, to the sixth level of the aura, we have allowed a connection to happen from the heart chakra and the celestial chakra. Through this, we can love not only our fellow man (the heart chakra) but do so with divine love (celestial chakra). The colors of this body are very soft in nature (pastel) and glow softly from the body.
The Seventh Layer (The Ketheric Template or Causal Body)
This is the mental level of the spiritual plane (whereas the celestial body is the emotional level of the spiritual plane). This body contains all the other bodies within it and extends up to three and a half feet from the body, often in the shape of an egg. Its structure is made of a gold, or silvery-gold, and appears as a grid type structure, which is very durable. It pulsates and vibrates at a very high speed and within this level; we "know" we are one with God. This body also contains the main Kundalini force that runs up and down the body.
Now while the Ketheric body is the last auric level in the spiritual plane, there are other planes (such as the Cosmic plane) but they do not relate to the aura for they are beyond the aura and a different article entirely!