Andromeda will plough straight through the Milky Way in roughly 4 to 4.5 billion years, and yet almost no two stars will collide, because the spacing between stars dwarfs the stars themselves by tens of millions of times. In about 5 billion years the Sun swells into a red giant and then shrinks to a white dwarf, never going supernova because it is far too light. Beyond that lies pure theory: star-forming gas runs dry around 10¹⁴ years, black holes evaporate through Hawking radiation, and proton decay has never once been observed.
Andromeda will plough straight through the Milky Way in roughly 4 to 4.5 billion years, and yet almost no two stars will collide, because the spacing between stars dwarfs the stars themselves by tens of millions of times. In about 5 billion years the Sun swells into a red giant and then shrinks to a white dwarf, never going supernova because it is far too light. Beyond that lies pure theory: star-forming gas runs dry around 10¹⁴ years, black holes evaporate through Hawking radiation, and proton decay has never once been observed.
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