About: Upagraha

In Jyotiṣa or Indian astrology, the term Upagrāha (Sanskrit: उपग्रह) refers to the so-called "shadow planets" (Sanskrit: छायाग्राह, chāyāgrāha) that are actually mathematical points, that are used for astrological evaluation. Upagrāha is a generic term used for two distinct and different calculations. One type of Upagrāha called Aprakāśa (अप्रकाश) is calculated from the degree of the Sun. Another type is more generally called Upagrāha or Kālavelā (कालवेला) is calculated by dividing duration of diurnal sky (from sunrise to sunset) or the duration of the nocturnal sky (from sunset to sunrise) into eight parts. The classic writers like Parāśara, Varāhamihira and later writers like Vankatesa Śarma, author of Sarvartha Chintamani, all classify the Upagrāhas in various ways.