SB 12.2.31
Devanāgarī
यदा देवर्षय: सप्त मघासु विचरन्ति हि । तदा प्रवृत्तस्तु कलिर्द्वादशाब्दशतात्मक: ॥ ३१ ॥
Text
yadā devarṣayaḥ sapta maghāsu vicaranti hi tadā pravṛttas tu kalir dvādaśābda-śatātmakaḥ
Synonyms
yadā—when;deva-ṛṣayaḥsapta—the seven sages among the demigods;maghāsu—in the lunar mansion Maghā;vicaranti—are traveling;hi—indeed;tadā—then;pravṛttaḥ—begins;tu—and;kaliḥ—the Age of Kali;dvādaśa—twelve;abda-śata—centuries [These twelve hundred years of the demigods equal 432,000 earth years];ātmakaḥ—consisting of.
Translation
When the constellation of the seven sages is passing through the lunar mansion Maghā, the Age of Kali begins. It comprises twelve hundred years of the demigods.