eta bhÄvi' kali-kÄle prathama sandhyÄya
avatÄ«rṇa hailÄ kṛṣṇa Äpani nadÄ«yÄya
eta - thus; bhÄvi' - thinking; kali-kÄle - in the Age of Kali; prathama - first; sandhyÄya - in the junction; avatÄ«rṇa hailÄ - descended; kṛṣṇa - Lord Kṛṣṇa; Äpani - Himself; nadÄ«yÄya - in Nadia.
The prathama-sandhyÄ is the beginning of the age. According to astronomical calculation, the age is divided into twelve parts. The first of these twelve divisions is known as the prathama-sandhyÄ. The prathama-sandhyÄ and Å›eá¹£a-sandhyÄ, the last division of the preceding age, form the junction of the two ages. According to the SÅ«rya-siddhÄnta, the prathama-sandhyÄ of Kali-yuga lasts 36,000 solar years. Lord Caitanya appeared in the prathama-sandhyÄ after 4,586 solar years of Kali-yuga had passed.