You are not worshiping the physical Sun; you are worshiping the Parabrahman within the sun. Not only you are worshiping the Solar God, you are also worshiping the Solar Shiva, the Solar Vishnu and the Solar Brahma because they are all part of the Solar Parabrahman. When you pray to the Solar God, you receive a lot of blessings. Repeating the Gayatri Mantra helps to develop the intuition of Buddhic Intelligence.
Source: Excerpt from The Inner Teaching of Hinduism Revealed, Master Choa Kok Sui 2004
You can also listen to this sacred chant on the Gayatri Mantra CD.