Ancient Atomic Mystery Found Miles Under the Pacific

Scientists have discovered an unexpected surge of rare atomic particles preserved in the Pacific Ocean floor from 10 million years ago, potentially unveiling either a dramatic shift in Earth’s ocean currents or the aftermath of an ancient cosmic event. The finding could provide a crucial new tool for dating geological history, much like a temporal fingerprint marking a specific moment in Earth’s past.

The discovery centers on beryllium-10, a radioactive isotope created when cosmic rays strike Earth’s upper atmosphere. Researchers found nearly double the expected amount of this rare isotope in deep-sea samples from a specific time period, challenging current understanding of Earth’s geological history.

“At around 10 million years, we found almost twice as much beryllium-10 as we had anticipated,” said Dr. Dominik Koll, physicist at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR). “We had stumbled upon a previously undiscovered anomaly.”

The research team, analyzing samples from several kilometers beneath the Pacific Ocean, found this mysterious spike consistently across multiple locations, confirming it wasn’t a mere sampling error. The samples came from ferromanganese crusts – rocky formations that slowly accumulated iron and manganese over millions of years, preserving within them a record of Earth’s past.

Two competing theories have emerged to explain this ancient anomaly. The first suggests a massive reorganization of ocean currents near Antarctica 10-12 million years ago. “This could have caused beryllium-10 to be unevenly distributed across the Earth for a period of time due to the altered ocean currents,” Koll explained. “As a result, beryllium-10 could have become particularly concentrated in the Pacific Ocean.”

The alternative explanation is more cosmic in nature: Earth might have experienced either increased cosmic radiation from a nearby supernova or temporarily lost its protective solar shield – the heliosphere – after colliding with a dense interstellar cloud. Either event could have led to a surge in beryllium-10 production.

The discovery’s significance extends beyond solving an ancient mystery. This anomaly could serve as a crucial temporal marker for dating geological samples, similar to how archaeologists use other isotopes to date more recent findings. However, while radiocarbon dating is limited to the past 50,000 years, beryllium-10 can help scientists peer millions of years into Earth’s past.

Using highly sensitive accelerator mass spectrometry at HZDR, the team could detect and measure individual beryllium-10 atoms, distinguishing them from other isotopes and molecules. This precision was crucial in confirming the anomaly’s existence.

The research group plans to analyze more samples from different ocean locations to determine whether this beryllium spike was a global phenomenon or limited to specific regions. If found worldwide, it would support the cosmic origin theory; if only in certain areas, it would suggest the ocean current explanation is more likely.

“Only new measurements can indicate whether the beryllium anomaly was caused by changes in ocean currents or has astrophysical reasons,” Koll noted, highlighting the need for further research to solve this ancient puzzle.

The findings, published in Nature Communications, represent a potential breakthrough in geological dating methods. For periods spanning millions of years, scientists have lacked reliable time markers to synchronize different geological records. This beryllium anomaly could provide that much-needed reference point, helping to align various geological archives and improve our understanding of Earth’s distant past.