Surya Yantra should be installed and worshipped when the planet Sun is malefic in the Birth Chart of a person. As per Ancient Vedic Texts, the Planet Sun is considered as the king of all planets. In fact, Sun is not a planet but it is a star because it is self illuminated. All the other planets including earth revolve around the Sun. Sun represents our Soul, Father, Power, Health, Fame, Government, Medicine, Gold, Bones, Fire as well as government jobs.