The word “ha” means sun; “ta” means moon. Without the sun and the moon, there is no Hata Yoga. The postures in Suryanamaskar are preparatory or balancing in nature between the Ida and Pingala (the left and right energy channels). Largely, it is called Suryanamaskar because it is mainly to activate the solar plexus, to raise the “samat prana” or the solar heat in the system. When we say “solar” it is not just symbolic. All heat that you experience on this planet is essentially from the sun — stored and released in many ways. Or, hydrocarbons have formed the way they have formed, essentially because they are sun-baked. If you take a piece of wood and burn it, it is only releasing solar energy. If the solar energy is taken away, the whole planet will freeze into solid ice.
Everything is run by solar power. You may think we are generating power by thermal or by gas, but everything is happening because of solar power. The only exception could be the breaking of the atom. That is not solar because you are not using the normal powerhouse of this system, which is the sun. When we activate the sun in the system, the body begins to glow and shine. If you have certain types of problems which manifest, usually in the form of excess mucus in the system — not just in your nasal passages, but all over — this can become balanced.
For one who is doing Suryanamaskar, glandular secretions and mucus levels will be very easily balanced and in good shape, and this determines a lot of things about you — not just your physical health. Your physical health, psychological health and spiritual possibility are determined by this, depending upon how much solar energy is within you. Or in other words, how balanced your secretions are. If your glandular secretions are slightly imbalanced, it is very hard to even sit and listen, forget about meditating or doing something else. It will make you feel crazy because the chemistry will go wonky. Suryanamaskar is one of the simplest and most effective sadhanas to bring that balance.
~ Adapted from Isha blog