
Rishi: Atharvanic tradition (specific ṛṣi not securely determinable from the provided excerpt alone)
Devata: Nakṣatra-rājan (Śakadhūma) with day/night and sun/moon as invoked supports
Chandas: Anuṣṭubh (probable; common in AV 6th kāṇḍa short charms)
Mantra 1
राजा शकधूमं नक्षत्राणि यद् राजानमकुर्वत । भद्राहमस्मै प्रायच्छन्निदं राष्ट्रमसादिति
When the Nakṣatras made the king—(even) Śakadhūma—Bhadrāham bestowed on him this realm: ‘So may this kingdom be.’
Mantra 2
भद्राहं नो मध्यंदिने भद्राहं सायमस्तु नः । भद्राहं नो अह्नां प्राता रात्री भद्राहमस्तु नः
Auspiciousness for us at mid-day; auspiciousness in the evening be ours. Auspiciousness for us through the days—at morning, at night—auspiciousness be for us.
Mantra 3
अहोरात्राभ्यां नक्षत्रेभ्यः सूर्याचन्द्रमसाभ्याम्। भद्राहमस्मभ्यं राजन्छकधूम त्वं कृधि
By Day and Night, by the Nakṣatras, by Sun and Moon—make for us a lucky day, O King, O Śakadhūma.
Mantra 4
यो नो भद्राहमकरः सायं नक्तमथो दिवा । तस्मै ते नक्षत्रराज शकधूम सदा नमः
Thou who hast made for us a lucky day, at eve, at night, and also by day—to thee, O King of the Nakṣatras, O Śakadhūma, be homage evermore.
It aims to secure “bhadrāham”—a lucky, auspicious day—by pacifying harmful time/astral influences and aligning the undertaking with day/night, sun/moon, and the nakṣatras.
Śakadhūma is addressed as a Nakṣatra-king (nakṣatra-rājan), a ruling astral power who can ‘make’ the day auspicious when invoked with the cosmic supports of time.
No special substances are required by the text. It can be used as a short recitation at the start of an important action, ideally with a clear intention for an obstacle-free, auspicious day.