In Egypt, the sun god was called Ra - depicted with a hawk head in many ancient characters. Ra was said to be the creator - the one who cried as he created the Earth (because it was so beautiful when he had finished) that the tears fell to the earth, and became people. Celtics actually had an ancient sun god by the name of Lugh. The Native Americans spoke of Tsohanoai, the god who carried the sun upon his back - across the sky - everyday. At night, he hung the sun from a peg in his house. Hence, that is why the moon is not as bright as the sun. The Aztec god, who also seemed the hardest to please, was named Huitzilopochtli. He was the sun and the war god, and was continuously offered human sacrifices to secure the plentiful ness of rain, as well as victory in wartimes.
The sun still gets its shining moment in today's tattoos (sorry about the pun). As cool as a sun tattoo had been in the past, it seems to have fallen by the wayside - replaced by other celestial bodies like the stars or moon.
When working at my family business as a teenager, it seemed that one of my stepfathers' best customers always came in bearing a new tattoo. His most significant tattoo on his body took up just about his entire back. It was a Native American Chief in full headdress, with his hands and face upturned to the sky, as if in prayers of thanks. On his left side, an eagle flew in the sky. The shadow of the eagle seemed to fall into the chief.
Source : http://ezinearticles.com/?Sun-Tattoo-Design&id=610295