Time goes by. And the dead Solar System continues to orbit the galactic centre just as it does today. Its journey takes it past stars young and old; carries it through the ghostly ruins of stars already dead – shrouds of gas ejected by planetary nebulae, or during the cataclysmic explosions known as supernovae. Ultimately the ashes of the star once known as the Sun are spread throughout the entire Milky Way galaxy, mixed indistinguishably with the remains of other stars, replenishing the interstellar medium from which they sprang billions of years earlier.

Then one day…

A massive star reaches the end of its life. It blows itself apart. Shockwaves from the supernova spread outwards from the epicentre through the interstellar medium like concentric rings on the surface of a lake. The waves compress the gas clouds through which they propagate. And eventually, somewhere, part of the cloud begins to contract under its own gravity. Millions of years later, a new star shines in the galaxy, born from the ashes of those long dead – including the Sun. Perhaps planets will also form around this new star – even life. And so it could be that the very atoms that currently comprise our bodies will one day find themselves part of a very different, alien creature. For the Universe is the ultimate recycling machine. We have come full circle.