Aṣṭamīअष्टमी(Ashtami)
The eighth tithi; devatā Rudra (Durgā in Kṛṣṇa-8), Jayā-class, classical register of intensity and Janmāṣṭamī observance.
Aṣṭamī
Aṣṭamī (अष्टमी, also written Ashtami) is the eighth of the thirty tithis, occurring in both Śukla-pakṣa and Kṛṣṇa-pakṣa. Its presiding devatā is Śiva — addressed in the Vedic-continuing register as Rudra for this tithi's classical context. In the five-class auspiciousness scheme of the Muhūrta Cintāmaṇi, Aṣṭamī belongs to the Jayā class (tithis 3, 8, 13) — the victory- oriented register. Several of the most significant annual lunar observances fall specifically on Aṣṭamī, notably Durgāṣṭamī in the Navarātri cycle and Kṛṣṇa Janmāṣṭamī in the Bhādrapada-Kṛṣṇa- Aṣṭamī register.
Classical grounding
Muhūrta Cintāmaṇi and the Nirṇaya Sindhu identify Śiva as Aṣṭamī's devatā. The Ṛgvedic Rudra hymns (2.33 especially) and later Śaiva texts establish the devatā continuity from the Vedic storm-god to the Puranic Maheśvara. The monthly Kālāṣṭamī (Kṛṣṇa-Aṣṭamī) observance is dedicated to Kāla Bhairava, a Śiva- form associated with time's dissolving register. Durgāṣṭamī falls on Āśvina-Śukla-Aṣṭamī during Navarātri and is the major annual Durgā observance. Kṛṣṇa Janmāṣṭamī — the most significant annual observance on Aṣṭamī — falls on Bhādrapada- Kṛṣṇa-Aṣṭamī and celebrates Viṣṇu's Kṛṣṇa-avatāra birth. The Jayā classification places Aṣṭamī among the victory-oriented tithis, with specific weight given to contests, formal confrontations, and completions of difficult undertakings.
Significations
What Aṣṭamī classically governs:
- Major ritual observances — Durgāṣṭamī, Kālāṣṭamī, Kṛṣṇa Janmāṣṭamī, and Rādhāṣṭamī (Bhādrapada-Śukla-Aṣṭamī) are the principal annual observances
- Śiva-oriented worship, particularly in the Rudra and Bhairava aspects; the Pradoṣa evening observance falls fortnightly on the Trayodaśī but draws on the Aṣṭamī register for broader Śaiva practice
- Victory in contested undertakings; the Jayā classification applies directly
- Avoidance of travel — classical muhūrta lists Aṣṭamī among the tithis classically avoided for travel initiation
- Śakti-oriented worship during Navarātri cycles — Durgāṣṭamī is the central tithi of the nine-day observance
Pakṣa-level reading
In Śukla-pakṣa, Aṣṭamī carries the waxing register with major observances including Rādhāṣṭamī (Bhādrapada-Śukla) and Durgāṣṭamī (Āśvina-Śukla, during Śāradīya Navarātri). The Śukla- Aṣṭamī first half carries Viṣṭi (the Bhadrā karaṇa), classically avoided for auspicious work — meaning the tithi's ritual observance is typically undertaken in its second half (Bava karaṇa) where classical muhūrta permits. In Kṛṣṇa-pakṣa, Aṣṭamī carries the waning register and the major Kāla Bhairava Aṣṭamī (Kālāṣṭamī) observance, with Kṛṣṇa Janmāṣṭamī (Bhādrapada-Kṛṣṇa-Aṣṭamī) as the annual peak. The Kṛṣṇa-Aṣṭamī half-tithis carry the movable karaṇas Bālava and Kaulava, both favourable.
Muhūrta-relevance
Classical muhūrta names Aṣṭamī among the tithis classically avoided for travel initiation, for marriage ceremonies, and for contract signing. The specific exceptions are Śiva-, Durgā-, and Kṛṣṇa- oriented observances, for which Aṣṭamī is precisely the correct tithi. Durgāṣṭamī during Śāradīya Navarātri is classically the most powerful Śakti-observance day of the year. The Viṣṭi karaṇa in the first half of Śukla-Aṣṭamī reinforces the general muhūrta avoidance register for that window.