Although Aruṇadeva sits in front of the sun-god and is engaged in driving the chariot and controlling the horses, he looks backward toward the sun-god.
In the Vāyu Purāṇa the position of the horses is described:
vahante vāmato ravim
cakre vākṣaḥ samāhitaḥ
Although Aruṇadeva is in the front seat, controlling the horses, he looks back toward the sun-god from his left side.