The Navagrahas (‘nava’ means nine and ‘graha’ means planet) are the deities representing the nine important celestial bodies, according to Hindu religion. They occupy an important role in Hindu religion and mythology. They are supposed to influence the lives of an individual.
Of the nine celestial bodies, the first seven are Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn. The remaining two, Rahu and Ketu are regarded as shadow planets. They do not have the ability to cast aspects, as other planets do, they do not rule any zodiacal signs and are not specified as male or female.
Each planet is represented by a deity as follows, Sun by Lord Agni, Moon by Goddess Apas, Mars by Goddess Bhumi, Mercury by Lord Vishnu, Jupiter by Lord Indra, Venus by Goddess Indrani, Saturn by Lord Yama, Rahu by Goddess Durga and finally Ketu by Lord Chitragupta.
The Hindu system of astrology, called the Vedic Astrology, is based on these nine bodies. Each of the planets has a particular effect on humans. Saturn, Rahu and Ketu have evil effects, while Jupiter, Venus, Mercury, Mars, the sun and the moon have favorable effects on humans. Before beginning any auspicious event, the goodwill of the navagraha is sought. The navagraha are also believed to influence the events related to a nation as well as the entire earth.
In addition to the navagraha, 27 constellations through which the moon passes and the 12 zodiac signs of the sun are also regarded as deities. They are consulted during important events like births, marriages and on occasions relating to happiness or calamity. In case of any unfavorable constellations, special ceremonies to appease the deities are held.