Jyotiṣa-śāstra Saṅgraha: Threefold Division, Gaṇita Methods, Muhūrta, and Planetary Reckoning
शंकुच्छायाहते त्रिज्ये विषुवत्कर्कभाजिते । लंबाक्षज्ये तयोस्छाये लंबाक्षौ दक्षिमौ सदा ॥ १३८ ॥
śaṃkucchāyāhate trijye viṣuvatkarkabhājite | laṃbākṣajye tayoschāye laṃbākṣau dakṣimau sadā || 138 ||
Apabila trijyā (jejari) didarab dengan bayang śaṅku (śaṅku-chāyā) lalu dibahagi menurut ukuran piawai ekuinoks dan Karkata (Cancer), nilai yang terhasil ialah lambākṣa-jyā, yakni “sin latitud”. Daripada dua bayang yang diperoleh itu, kedua-dua latitud hendaklah sentiasa diambil sebagai selatan (dakṣiṇa).
Sanatkumara (teaching Narada in a Vedanga/astronomical context)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: adbhuta
It shows that Narada Purana integrates Moksha-oriented teaching with Vedāṅga Jyotiṣa: precise knowledge of time, direction, and seasonal markers supports correct dharma-practice and disciplined living.
Indirectly: by emphasizing accurate astronomical reckoning (equinox/seasonal measures), it safeguards the proper timing of vrata and pūjā—practical supports that strengthen steady Vishnu-bhakti.
Vedāṅga Jyotiṣa and mathematical astronomy: using a gnomon’s shadow with trijyā and jya (sine) operations to derive lambākṣa (latitude) and determine southern orientation.