The Sun is the charioteer, the leader of the Navagraha. Not unlike the CEO of a company, the Sun is knowledgeable on the roles and responsibilities of the other grahas and has the ability to inspire and integrate all aspects of consciousness within the human experience.
The Moon is feminine, soft, compassionate. She is the Mother and as such she is governs the HEART of the human experience. Her power lies in graceful surrender, to let go and let God.