An ancient Hindu festival, dedicated to Lord Surya and Chhathi Maiya (known to be the sister of Surya), Chhath Puja is unique to the states of Bihar, Jharkhand, Eastern Uttar Pradesh and the country of Nepal. It is the only Vedic festival that is dedicated to the Sun God, who is supposed to be the source of all powers and Chhathi Maiya (another name for Goddess Usha from the Vedic period). The god of light, energy and life force is worshipped in order to promote well being, development and the prosperity of human beings. Through this festival, people aim towards thanking the Sun God for a period of four days. The devotees who observe the fast during this festival are called Vrati.