Rishi: Madhucchandā Vaiśvāmitra (traditional attribution for RV 1.1–1.11; RV 1.3 commonly placed under Vaiśvāmitra-collection—exact rishi for this specific mantra varies by anukramaṇī traditions)
Devata: Sarasvatī (as inspirer of dhī and luminous guidance)
Chandas: Gāyatrī (3 pādas of 8 syllables; standard for early Mandala 1 invocations)
Samhita Patha (Devanagari)महो अर्णः सरस्वती प्र चेतयति केतुना । धियो विश्वा वि राजति ॥
Samhita Patha (IAST)म॒हो अर्ण॒: सर॑स्वती॒ प्र चे॑तयति के॒तुना॑ । धियो॒ विश्वा॒ वि रा॑जति ॥
Transliterationmaho arṇaḥ sárasvatī prá cétayati ketúnā | dhíyo víśvā ví rājati ||
TranslationSarasvatī, the vast flood of luminous plenitude, awakens (in us) by her banner of discernment; and all the inspired thoughts shine out in their full radiance.
Padapatha (Word Analysis)म॒हः । अर्णः॑ । सर॑स्वती । प्र । चे॒त॒य॒ति॒ । के॒तुना॑ । धियः॑ । विश्वाः॑ । वि । रा॒ज॒ति॒ ॥महः । अर्णः । सरस्वती । प्र । चेतयति । केतुना । धियः । विश्वाः । वि । राजति ॥mahaḥ | arṇaḥ | sarasvatī | pra | cetayati | ketunā | dhiyaḥ | viśvāḥ | vi | rājati
Word by Wordअर्णःflood, wave, stream (waters) सरस्वतीSarasvatī (the goddess/river) चेतयतिmakes known, causes to perceive, awakens केतुनाby (her) banner/sign, by her light/mark धियःthoughts, insights, prayers विapart, widely, distinctly राजतिshines, is resplendent 
