Sankranti means "transition". In the Panchang it is the exact moment the Sun crosses from one sidereal sign (rashi) into the next. There are twelve Sankrantis a year, one for each sign, and each begins a solar month. Two are especially celebrated: Mesha Sankranti, the solar new year in many regions, and Makar Sankranti.
Makar Sankranti and its date
Makar Sankranti is the Sun's entry into sidereal Makara. Because it follows the Sun rather than the Moon, its Gregorian date is nearly fixed: around 14 or 15 January in our time.
It is not permanently fixed, though. The sidereal zodiac is measured from the stars, while the Gregorian calendar follows the tropical year. Because of the precession of the equinoxes (reflected in the ayanamsa), the sidereal ingress drifts later by roughly one day in about 70 years. Over many centuries it has moved from late December towards mid-January, and it will continue to move slowly later.
Which day is observed?
The ingress is an instant that can fall at any hour. This platform follows the rule used by most North Indian Panchangs: if the Sankranti moment is before local sunset, that day is observed; if it is after sunset, the observance moves to the next day. Tamil, Kerala and Bengal rules for the start of the solar month differ slightly. Traditions vary by region and Panchang convention.
Punya kaal
The hours around a Sankranti are traditionally called punya kaal, a period considered especially meritorious for a holy bath (snana), charity (daan) and Surya worship. Panchangs describe a longer punya kaal and a shorter, more intense maha punya kaal; their exact spans vary between traditions.
Uttarayana: tropical and traditional
Makar Sankranti is popularly associated with Uttarayana, the Sun's "northward" half-year. Astronomically, the Sun actually begins moving north at the winter solstice, around 21 December, which is the tropical Uttarayana. The traditional association with Makar Sankranti comes from an era when the two nearly coincided; precession has since separated them by a few weeks. The Panchang on this site shows both the tropical and the sidereal ayana.
One festival, many names
- Pongal in Tamil Nadu, beginning the solar month Thai
- Lohri in Punjab, celebrated on the eve of Makar Sankranti
- Uttarayan in Gujarat, famous for kite flying
- Bhogali (Magh) Bihu in Assam
- Khichdi in parts of Uttar Pradesh and Bihar
See this year's timing on the Makar Sankranti page, and read Ayanamsa and Panchang differences to see why the moment can differ by minutes between Panchangs.