Antarctic ice cores reveal Earth's 80,000-year passage through supernova dust
Updated
Updated · ScienceAlert · May 11
Antarctic ice cores reveal Earth's 80,000-year passage through supernova dust
11 articles · Updated · ScienceAlert · May 11
Dominik Koll's team found iron-60 in EPICA Antarctic ice dated 40,000 to 81,000 years old after analysing 295kg of samples, with results published in Physical Review Letters.
The isotope forms in supernovae and exceeds expected cosmic-ray background levels, indicating interstellar origin and suggesting the Solar System moved from a sparser into a denser part of the Local Interstellar Cloud.
Researchers say the ice preserves a time profile of changing local interstellar conditions and may help map the cloud's structure, while implying Earth could still be passing through iron-60-bearing debris today.
This 'flight record' in ice reveals our cosmic past. What does it predict about the interstellar clouds our solar system faces next?
As NASA's IMAP samples space dust, how will its live data compare to the ancient 'flight record' frozen in Antarctic ice?
We are flying through denser supernova debris than in the past. Could this cosmic dust be affecting our climate or technology?
Iron-60 in Antarctic Snow: Direct Evidence of Recent Supernova Dust Deposition on Earth
Overview
Scientists have discovered the radioactive isotope Iron-60 in Antarctic ice and snow, providing direct evidence that Earth has encountered material from distant supernova explosions. Iron-60 is only created in these powerful stellar events, so its presence on Earth is a clear sign of extraterrestrial origins. The supernovae that produced this Iron-60 were close enough for their ejecta to reach our planet in detectable amounts, but not so close as to cause harm. As our Solar System traveled through the Local Interstellar Cloud, Earth became littered with Iron-60 particles, linking our planet to dramatic cosmic events in our galactic neighborhood.