Aaron Alien/Alamy
When the sun eventually expires and swells to engulf Earth, might the remnants of landfill and deeply buried nuclear waste be recycled to form star dust that will become new planets or life forms? (continued)
Clémence Fontanive
Institute for Astronomy, University of Edinburgh, UK
In principle, yes: atoms in landfill, buried nuclear waste and everything else on Earth may eventually be recycled into the wider cosmos and contribute to future worlds. But the reality is a bit less direct than “today’s rubbish becomes tomorrow’s life”.
First, Earth’s fate is still uncertain. We don’t actually know whether the expanding sun will engulf our planet or whether Earth may just avoid being swallowed. The timescale and pathway by which Earth’s material will be dispersed back into space will depend on which of these outcomes occurs.
Either way, there is also no guarantee that the sun’s remains will produce new planets after its death. We have little evidence that new planetary systems commonly form around stellar remnants, so much of the material shed by the dying sun may simply drift through interstellar space.
As for the nuclear waste itself, it is unlikely to play any special role in future biology. Life mostly runs on abundant, light elements such as carbon, hydrogen, oxygen and nitrogen. Heavier elements found in nuclear waste are generally poor biological building blocks.
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You owe me an apology, 91av – I ended up with a pile of blackened peas and had to spend hours cleaning the pan
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Still, given time, some of those atoms may one day become part of interstellar clouds, new stars or future planets. In that sense, a future organism somewhere in the galaxy could contain an atom that once sat in a landfill on Earth. It just probably won’t owe much of its biology to nuclear waste.
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