Everything we see and touch is made up of atoms, and those atoms had to come from somewhere. The smallest – hydrogen and helium atoms – were formed in the Big Bang (which, incidentally, was not particularly loud). Inside the extremely hot cores of stars, hydrogen and helium atoms are fused to make bigger atoms – beryllium, barium, lithium, the carbon and oxygen that makes up more than 80% of our bodies. When the biggest stars die they explode, releasing enough energy to fuse much larger atoms. All the gold and silver on Earth came from stars that exploded.

Carl Sagan invited us all to consider the journeys that the atoms of everyday things have taken, and in doing so made the mundane a little more incredible.

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