Trayodashi

Trayodashi hosts the Pradosh (twilight) window — the 1.5 hours spanning sunset when Shiva dances his Tandava. This is why Pradosh Vrat (see data/vrats.js) is observed on Trayodashi. Kartik Shukla Trayodashi is Dhanteras (Dhan = wealth, Teras = 13th) — the day Dhanvantari (physician of the gods) emerged from the ocean of milk carrying amrita. Buying gold, silver, or utensils on Dhanteras is considered the most auspicious purchase of the year.

1. 1Every Trayodashi: observe Pradosh Vrat — see data/vrats.js Pradosh Vrat protocol
2. 2On Dhanteras: light a 4-wicked diya (south-facing) for Yama; light other diyas for Lakshmi
3. 3Worship Dhanvantari with yellow flowers and tulsi — pray for health of the family
4. 4Buy gold, silver, or copper utensils during the auspicious Dhanteras window