{"id":"vidhyamitra:day:1620-12-21:en","page_class":"VM-1-day","url":"https://vidhyamitra.com/day/1620-12-21","language":{"target_lang":"en","base_lang":"en","quality_tier":"canonical"},"data":{"date":"1620-12-21","date_display":"December 21, 1620 CE","panchanga":{"method":"Sūrya Siddhānta + Bhāskara-II iterative manda + Kerala-school (Mādhava-Nīlakaṇṭha) evection + variation + annual equation","engine_version":"2.0 (Kerala-school enhanced)","accuracy_note":"Sub-degree on Moon at any Kali-Yuga date (~2-5° residual max)","tradition_chain":"Āryabhaṭa(499) → Brahmagupta(628) → Bhāskara II(1150) → Mādhava(~1400) → Parameśvara(1430) → Nīlakaṇṭha(1501) → 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