Puthandu is the Tamil new year, the first day of Chithirai, fixed by the Sun’s entry into Mesha rather than by the Moon. Tamil Nadu dates it by sunset — if the Sun crosses into Mesha before it goes down, that day is Chithirai 1 — which is why Puthandu and Kerala’s Vishu, the same astronomical instant, do not always fall on the same day.
How it is observed
The year is met with the kanni: a tray of fruit, gold, betel, a mirror and a lamp, arranged so it is the first thing seen on waking. The new year’s panchangam is read aloud at the temple, and the meal turns on mangai-pachadi, which carries all six tastes because the year ahead will too.