Rahu is a snake that swallows the sun or the moon causing eclipses. It is popularly called the Planet of Success but it is not actual planet. It it is an intelligent concept unique to Indian astrology. Rahu is believed to represent the head of the demon.

Rahu and Ketu are two parts of the same danava and are 180° apart from each other. Rahu is responsible for solar, Ketu for lunar eclipse. The myth of Rahu and Ketu sheds much light on their function and greater possibility. Rahu is a head without a body. Rahu is material and loses the essence of things in their substance.