Rahu and Ketu are the two points of intersection of the orbit of the Moon and the orbital plane of the Sun, when observed with respect to the Earth, that is geocentric Solar system. In our traditional Vedic Astrology they are referred as the Shadow planets with the form of a headless/serpent headed person. Hence, Rahu rules temptations and worldly things and will never be satisfied with small benefits but will opt for the lion's share. Rahu is a warrior. He is anxious, he is brave. Hence, the natives influenced by Rahu will have the quarrelling type of mentality. The mode of transport for Rahu in mythology is Lion, and the lion is an animal that does not hunt when not hungry. Likewise, the natives ruled by Rahu will relax and strike/hunt only when there is a necessity. Rahu is also called dragon's head by Western Astrologers. Rahu in Astrology is a very unsteady and erratic force ruled by obsessive passions and unconcerned with ethical notions of right and wrong. Because of this, Rahu can bring great material progress, though any success gained under its influence is likely to be short-lived. Rahu is tricky and sneaky and creates illusions of all kinds. It especially manifests in one's compulsions of uncontrollable passions. Ketu is also an unsteady and sometimes treacherous force, but its qualities are more of an abstract, inward nature, in contrast to Rahu who is more concerned with outward, worldly matters.