Just as the Sun and planets were born, they will eventually die.
In 5 billion years, the Sun will cool and bloat outward to many times its current diameter (becoming a red giant) before casting off its outer layers as a planetary nebula and leaving behind a stellar corpse, a white dwarf. The planets will follow the Sun's course; in the far distant future, the gravity of passing stars will gradually whittle away at the Sun's retinue of planets. Some will be destroyed, others will be ejected into interstellar space, but ultimately, over the course of trillions of years, the Sun will be left alone with no other bodies in orbit.
I am sad. I'd like to be alive to watch this. Perhaps I am mistaken and there is an afterlife. I will seat myself in the front row and watch forever. If death is like that, how peaceful it will be. To drift and watch forever.