Did Earth once feel the blast of a nearby Supernova?

WEB DESK: A startling discovery from the depths of the Pacific Ocean is leading scientists to a profound conclusion: Earth may have been showered with the radioactive debris of a dying star millions of years ago. A groundbreaking new study from Germany posits that our planet drifted through the aftermath of a nearby supernova approximately 10 million years ago, with the evidence preserved in an ancient marine layer.

An Anomaly at the Bottom of the Sea

The key evidence lies not in a flash across the sky, but in a subtle geochemical signature. Researchers analyzing deep-sea sediment cores uncovered a surprising and concentrated spike of a radioactive isotope called beryllium-10. While this isotope is constantly formed when cosmic rays strike Earth’s atmosphere, its levels are typically steady. The discovery of a massive, dated accumulation from the Late Miocene epoch, about 10 million years ago, points to a dramatic, singular event that dramatically increased its production.

“An anomalous event caused this spike,” the research suggests, with one of the most compelling explanations being a stellar explosion relatively close to our solar system.

Rewinding the Galactic Clock

To test this hypothesis, the team turned to cosmic cartography. Using data from the European Space Agency’s Gaia space observatory, they meticulously traced the movements of our Sun and 2,725 nearby star clusters over the past 20 million years. Their goal was to calculate the probability of a supernova occurring close enough to bathe Earth in its fallout.

The results were striking. The models revealed a 68% chance of a star exploding within 326 light-years of the Sun within a million years of the beryllium-10 peak. Of the thousands of clusters mapped, 19 were identified as having a greater than 1% probability of hosting such an event at the right time and place.

A Compelling but Incomplete Case

Despite the strong circumstantial evidence, the case for a supernova is not yet closed. The study’s authors urge caution, noting significant hurdles. The beryllium-10 anomaly has so far only been found in one ocean, and other telltale isotopes from supernovae, like iron-60, are absent from the same geological layer.

“Our results support the possibility of a supernova origin for the beryllium-10 anomaly,” the team concluded, highlighting the Sun’s proximity to the star-forming Orion region at that time as a favorable factor. However, they acknowledge that local forces, like shifts in ancient ocean currents, could have concentrated the isotope, creating a false signal.

The path to confirmation now lies in a global search. If a cosmic event is truly to blame, its fingerprint, the same distinct isotope peak, should be found in sediment samples from around the world. Unraveling this 10-million-year-old mystery will require reading the Earth itself, one ancient layer at a time.