Jyotiṣa-śāstra Saṅgraha: Threefold Division, Gaṇita Methods, Muhūrta, and Planetary Reckoning
तद्वर्गतो दशगुणात्पद भूपरिधिर्भवेत् । लंबज्याघ्नस्वजीवाप्तः स्फुटो भूपरिधिः स्वकः ॥ ८४ ॥
tadvargato daśaguṇātpada bhūparidhirbhavet | laṃbajyāghnasvajīvāptaḥ sphuṭo bhūparidhiḥ svakaḥ || 84 ||
De diez veces el cuadrado de ese valor se obtiene, por pasos, una circunferencia aproximada de la Tierra. Mas la circunferencia exacta se logra al multiplicar por el seno de la distancia al cenit (lamba-jyā) y luego dividir por el propio valor de jīva (seno).
Narada (teaching in a technical/astronomical context within Moksha-Dharma discourse)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: adbhuta
It shows that Narada Purana integrates dharma with disciplined knowledge—precision (sphuṭa) and correct method are themselves part of righteous learning that supports clarity of understanding.
Indirectly: it frames sacred study as orderly and exact, encouraging a devotee to approach Vishnu’s cosmos with reverence and intellectual honesty rather than guesswork.
Vedāṅga Jyotiṣa/gaṇita: the verse references jyā/jīva (sine) operations and distinguishes approximate versus accurate computations for determining bhū-paridhi (earth’s circumference).