Upagrahas are the non-luminous ('aprakasha') grahas: points computed from the Sun's or Saturn's position, with no body and no orbit, which afflict the house they fall in. There are two families - the five derived from the Sun (Dhuma, Vyatipata, Parivesha, Indrachapa and Upaketu) and the Saturn-derived Gulika and Mandi, computed from the division of the day or night into eight parts.