The actual Gayatri Mantra is written in Yajurved Adhyay 36, Mantra 3. The key point is that it doesn't have the word "Om" () in the beginning. The mantra "Om" has been added by ignorant saints.

Yajurved Chapter 36 Verse 3

BhoorbhuvH swaH tatsaviturvareniyam bhargo devasya dheemahi dheeyo yoH naH prachodyaat.

Division of words: BhooH – bhuvH – swaH – Tat – savituH – vareniyam – bhargH – devasya – dheemahi – dheeyaH – yaH – naH – prachodyaat.

Translation: - Brahm, the giver of the knowledge of Vedas, is saying that (SwaH) His personal blissful (bhuvH) in space i.e. Satlok and Anamay Lok (bhooH) one who Himself appears is Complete God. He only (savituH) giver of all the happiness, the Creator of all, is the God (Tat) that hidden i.e. invisible, but in form (vareniyam) greatest of all (bhargH) with an effulgent body, Creator of the entire Nature (devasya) of Supreme God (dheemahi) prayer, worship according to the scriptures i.e. wisely with full consideration (yaH) the God who is the Nurturer of all. He may (naH) free from misconception (dheeyaH) to wisely i.e. virtuous disposition do scripture-based true bhakti (prachodyat) inspire everyone.

Translation:- Brahm, the giver of the knowledge of Vedas, is saying that Complete God Himself appears in His blissful space i.e. Satlok and Anamay lok. He alone is the giver of all the happiness and the Creator of all. Worship that Supreme God, who is hidden i.e. invisible, but in form, Greatest of all, has an effulgent body, Creator of the entire Nature, according to the scriptures i.e. wisely with full consideration. That God, who is the Nurturer of all, may inspire everyone to wisely do doubt-free scripture-based true bhakti.

Meaning: - In this Verse 3, there is endorsement of the Yajurved Chapter 40 Verse 8 that the (Kavirmanishi) complete scholar, i.e. who knows about the past, present and future, is Kavirdev (Supreme God Kabir). He does not have a body of the five elements (swayambhuH paribhuH) that God appears Himself. The body of Complete God is made up of one element. Therefore, in Yajurved Chapter 1 Verse 15 and Chapter 5 Verse 1, it is said that {(AgneH) Supreme God (tanuH) an effulgent body (asi) has} Supreme God has an efflugent body. Do the bhakti of that Almighty, kind, happiness-giving God with a true heart and according to the scriptures. That Complete God manifests in the Satlok above. We pray to Him that, that God may inspire all the living beings to do scripture-based worship.

The mantra "Om" in the front has been added by ignorant saints