The Gāyatrī Mantra, also known as the Sāvitrī mantra, is a highly revered mantra from the Rig Veda (Mandala 3.62.10), dedicated to Savitr, the Sun deity. Gāyatrī is the name of the Vedic meter in which the verse is composed.[1] Its recitation is traditionally preceded by oṃ and the formula bhūr bhuvaḥ svaḥ, known as the mahāvyāhṛti, or "great (mystical) utterance".
om bhūr bhuvaḥ svaḥ
tát savitúr váreṇ(i)yaṃ
bhárgo devásya dhīmahi
dhíyo yó naḥ prachodayāt
– Rigveda 3.62.10[11]