Saura-mata is an amalgam of an endogenous layer of solar deities going back to the #Veda and neo-morphic layer of Iranic origin & while all Vedic deities have a solar character, most prominent are Ādityas.
ndra is the Indo-Aryan version of the preeminent deity of the ancestral Indo-European pantheon. In the Vedic texts, we see remnants of what might have been an ancient tripartition of this deity, as manifest on the earth, in the atmosphere and in the heavens.