Scientists have found fossil evidence on Earth of a supernova that occurred 2 million years ago, more than 300 light-years away.  What’s more, this supernova may have contributed to an extinction-level event in Earth’s prehistoric past.

A supernova is the explosion of a star in outer space.  Due to the massive release of energy, it may shine with the brightness of 10 billion suns.  One of the byproducts of a supernova is Iron-60, a mildly radioactive form of iron that is not produced naturally on Earth.  Any ⁶⁰Fe found on Earth or the moon is almost certainly dust from a supernova.

German researchers extracted core samples from beneath the Pacific Ocean that date from 2.6 million to 2.8 million years ago.  Within fossilized crystals of the mineral magnetite, they found still-live atoms of the rare ⁶⁰Fe radioisotope.

According to space.com, this finding is consistent with previous studies that suggest a supernova 325 light-years from Earth blasted the planet with iron ash about 2 million years ago.  This event coincided with an extinction-level event in Earth’s prehistory that killed off mollusks such as marine snails and bivalves, and was followed by a period of global cooling.

Agilent technologies have been used in the study of the early solar system.

French researchers studied ⁶⁰Fe and other short-lived radionuclides found in meteorites to refine the chronology of the early solar system.  They used an Agilent ICP-MS to measure the concentrations of these rare metals.

UK and Swiss researchers also used an Agilent ICP-MS to develop a method for the precise and accurate determination of the tellurium (Te) isotope in meteorites.  The researchers believe that the presence of ¹²⁶Te excesses from the decay of ¹²⁶Sn (a short-lived nuclide of tin) provides strong evidence that a supernova triggered the formation of our solar system.

For more information go to:

• What is a Supernova? (NASA)
• Supernova Ashes Found in Fossils Hint at Extinction Event (space.com)
• Time-resolved 2-million-year-old supernova activity discovered in Earth’s microfossil record
• Iron-60 Heterogeneity and Incomplete Isotope Mixing in the Early Solar System
• Tellurium isotope compositions of calcium-aluminum-rich inclusions
• Agilent ICP-MS Systems