What Will Eventually Happen to the Sun? KehlBayern June 4, 2014 Science & Technology Eternal though it may seem, our local star, Sol, is not immortal. Indeed, approximately 500 years from now, our sun will become a red giant star, engulfing all of the inner planets except for Mars. Then it will gradually shrink to nothing but a mere shadow of its former self and our solar system will be finished for the remainder of the lifespan of the universe. Cool stuff, eh?