The remnant of a supernova. Photo: NASA/CXC/F. Vogt et al./ESO/VLT/MUSE/STScI

Radioactive dust sent out by ancient supernovas has been found in Antarctica, according to a new study in the journal Physical Review Letters.

The big picture: Researchers behind the study suggest that our solar system is currently flying through a cloud of cosmic material thought to be shaped by supernovas.

  • Those stellar explosions may leave behind traces of the radioactive isotope iron-60, which the scientists found in Antarctic snow.
  • This study and future work could help explain more about our solar system’s past and its movements through the Milky Way, according to a synopsis published by the American Physical Society.

What they found: The team behind the study thinks that the iron-60 atoms found in the region were delivered to Earth in the last 20 years.

  • "I think Earth essentially picked [the element] up during the movement through the cloud, not like a real injection as you would expect from a very near supernova," Dominik Koll, an author of the study, tells Axios by email.
  • The scientists had been concerned that the isotope might have been created by nuclear weapons, but the team ruled that out when the other concentrations of bomb-created isotopes didn't match what they found in Antarctica.

What's next: Koll and his colleagues are hoping to get a look at older Antarctic snow in order to compare concentrations of iron-60 in the past to those found today.

  • Older samples may reveal exactly when our solar system traveled into the supernova-enriched cloud it appears to find itself within now.

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