A team of astrophysicists and geochemists has discovered traces of interstellar dust from distant supernova explosions in Antarctic ice layers. Earth has passed through regions of varying density in space over tens of thousands of years, and this process is reflected in the ice. The key to the study was the radioactive isotope iron-60, considered 'supernova ash'. This is reported by Ixbt.com news.
Scientists analyzed hundreds of kilograms of ice and snow samples dating from 40,000 to 80,000 years ago. Using mass spectrometry to count iron-60 atoms, they found that their concentration was significantly lower in the past than it is today. This is explained by the Solar System's movement through local interstellar clouds consisting of gas, plasma, and stardust.
Currently, the Solar System is passing through the 'Local Interstellar Cloud', and modern models suggest this process will last between 40,000 and 124,000 years. Antarctic ice sheets serve as a unique archive for studying the history of the cosmic environment, as snow layers there remain almost unchanged for millennia.
Researchers note that this method allows for the analysis of 'cosmic sediment' that has settled directly on Earth, unlike observations made via telescopes. However, the lower-than-expected amount of iron-60 necessitates a revision of the theory regarding the origin of interstellar clouds. Scientists now plan to reconstruct the Solar System's past galactic trajectory by studying even older ice layers.
Read “Zamin” on Telegram!
