Traces of iron-60 have been found in Antarctic ice.
Why it is true
Iron-60 is a radioactive isotope produced in supernovae that does not occur naturally on Earth. In 2025, scientists analysed 300 kilograms of Antarctic ice aged 40,000 to 80,000 years and found atoms of this isotope, confirming that Earth has been passing through a cloud of stellar debris for tens of thousands of years.
Source: Physical Review Letters
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