The supreme deity of the Sumerian pantheon is AN, or Anu. In the first two letters of the Sanskrit word An-gir-as, AN could refer to Anu. GIR might relate to the Akkadian fire-god— fire as in rocket propulsion. DinGIR in the cuneiform writing meant sky or heaven, and also a god or goddess. The masters of the sky were perceived as deities by the earthbound. This reminds of Angiras and his descendants, the Angirasas, as a group of higher beings who traversed the realms between gods and men — an inter-stellar and inter-dimensional elite.The name Anu or Ânava for the Iranians appears to have survived even in later times: the country and the people in the very heart of Avesta land, to the immediate north of Hâmûn-i Hilmand, were known as late as Greek times as the Anauon or Anauoi. The names of Anu tribes in the Rigveda and the Puranas can be clearly identified with the names of the most prominent tribes among latter-day Iranians." [Shrikant G. Talageri]. 
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