The grahas are the celestial bodies of Vedic astrology: the Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn, together with the lunar nodes Rahu and Ketu, making nine in all. The Sanskrit word means "seizer" or "grasper", reflecting an understanding of them as forces that take hold of a life rather than as inert points on a chart.
Each graha rules signs, governs significations, and gives results according to its dignity, house and combinations. The two nodes, Rahu and Ketu, are not physical bodies but the points where the Moon's path crosses the ecliptic, and they are treated as shadowy planets with powerful effects.