In Vedic astrology and traditional Hindu timekeeping, Rahu Kaal (also spelled Rahukalam or Rahu Kalam) is a daily daytime period lasting approximately 90 minutes. It is governed by Rahu, the northern ascending node of the Moon. In astronomy, Rahu is not a physical planetary body, but a calculated intersection point where the Moon's orbit crosses the apparent path of the Sun.
Puranic accounts describe the churning of the cosmic ocean (Samudra Manthan), during which the Asura Swarbhanu drank the nectar of immortality. Alerted by the Sun and Moon, Lord Vishnu used the Sudarshana Chakra to divide the form into two entities: the head became Rahu and the torso became Ketu.
Because Rahu holds a natural tension with the luminaries (Sun and Moon), this daily daytime window is associated with sudden impulses, distraction, and unexpected delays. Initiating fresh investments or contracts during this window frequently requires later rework.