Uttarayana & Dakshinayana
- Kishore S Kumar
This animation illustrates the apparent annular movement of the Sun between the Tropics of Cancer and Capricorn (the apparent movement caused by the Earth's axial tilt). The Surya Siddhantha designates the movement from the winter solstice to the summer solstice as Uttarayana (northward movement) and the reverse movement as Dakshinayana (southward movement). Yet another ancient, early Vedic tradition designated the movement from the vernal equinox to the autumnal equinox (when the Sun is North of the Equator) as Uttarayana (northern movement) / Devayana and the reverse movement (when the Sun is to the South of the Equator) as Dakshinayana (southern movement) / Pitrayana. This earlier tradition is consistent with another tradition (which is current even today) of dedicating the northern hemisphere to the gods (devas ) and the southern hemisphere to the ancestors (pirtus). Both these traditions are illustrated in this animation. This animation also highlight the correlation of some Hindu festivals with Uttarayana and Dakshinayana.
- The Hindu New Year day - Sauramana Yugadhi - coincides (subject to a 24 days lag caused by the precession of the equinoxes) with the Vernal Equinox, which is the beginning of Uttarayana as per the early Vedic tradition.
- The Pitru Paksha (fortnight of the ancestors) spans the Autumnal Equinox which is the beginning of Dakshinayana as per the early Vedic tradition. This is consistent with the tradition of dedicating the southern hemisphere to the ancestors (pitruloka / yamaloka)
- Makara Sankranthi coincides (subject to a 24 days lag caused by the precession of the equinoxes) with the beginning of Uttarayana as per the Surya Siddhantha definition.