If the Sun loses fuel, does that correspond to Surya the Sun god getting old? If the Sun burns out, does that correspond to Surya dying? What does Hindu scripture have to say on the subject of Surya getting old or dying?
The Vedas mention Sun or Lord Surya as the inner soul of everything. So, needless to say there is no question of that eternal Sun (mentioned in Vedas) ever dying.
Surya AtmA jagatah tasthushah cha.
The Sun is the soul of all that is dynamic and static.
Atharva Veda Samhita, KAnda 13, Sukta 2, Mantra 35.