Graha–Ketu–Utpāta Lakṣaṇas: Solar/Lunar Omens, Comets, Eclipses, and Calendar Rules
षण्मासवृद्ध्या ग्रहणं शोधयेद्र विचंद्र योः । पर्वेशास्तु तथा सत्यदेवा रव्यादितः क्रमात् ॥ ८१ ॥
ṣaṇmāsavṛddhyā grahaṇaṃ śodhayedra vicaṃdra yoḥ | parveśāstu tathā satyadevā ravyāditaḥ kramāt || 81 ||
En ajoutant la correction de six mois, on doit calculer et vérifier les éclipses du Soleil et de la Lune. De même, les seigneurs des jours de jonction (parvan) doivent être déterminés dans l’ordre prescrit—à commencer par le Soleil—avec les Satya-deva qui leur sont associés.
Sanatkumara (in instruction to Narada within the Moksha-Dharma discourse, touching Vedanga-style calendrical science)
Vrata: none
Primary Rasa: shanta
Secondary Rasa: adbhuta
It links dharma to correct time-reckoning: sacred observances depend on accurate parvan and eclipse determination, so spiritual practice is aligned with cosmic order (ṛta).
Indirectly: bhakti-oriented vratas and worship performed on parvan days or during eclipse-related rites require proper calendrical knowledge; devotion is strengthened when worship is done at the right sacred times.
Vedāṅga Jyotiṣa: the verse indicates a rule of correction (six-month adjustment) for checking solar/lunar eclipses and determining parvan presiding deities in proper sequence.