Concept of Relative Motion in Jyotish or Astrology: -
In Indian Vedic Astrology we have to work according to the concept of relative motion & Earth is assumed to be stationary. While Sun & Moon are considered to be planets. Also two imaginary planets 'Rahu' (Dragon's Head) & 'Ketu' (Dragon's Tail) are taken into consideration. These two imaginary planets are actually two points on which the Moon's orbit & Earth's Equator (extended into the space) intersects. Other planets are Mars (Mangal), Mercury (Budh), Jupiter (Guru), Venus (Shukra), Saturn (Shani). Newly discovered planets like Uranus, Neptune, Pluto etc. are not taken into consideration.