Supernova Debris Affected Climate, Evolution of Life on Earth Says Study

Studies confirmed that supernovae, or multiple instances of violently exploding stars, have showered the Earth with radiation in the last few million years. A study said that traces of the radioactive iron-60 - an indicator of supernova debris - were found buried in the sea floor. Another research modeled the specific debris that have splattered the isotope in our galactic neighborhood.

However, according to the BBC the periods of bombardments did not coincide with mass extinction events, which means that they are not close enough to unleash their level of destruction - but they were close enough to have affected the climate and evolution of life on earth.

The iron-60 which has a half-life of 2.6 million years, can't have originated from the earth's formation. The Los Angeles Times noted that using isotopic evidence, researchers found that they were present in two spans - from 3.2 million to 1.7 million years ago, and from 8.7 million to 6.5 million years ago, hinting that there may have been a series of these supernovae that have showered the earth with debris, therefore indicating that our solar system was passing by a neighborhood that was "polluted" by these pieces of dead stars.

Either way, these periods overlapped with the most significant changes our earth has gone through, most recently matching with the onset of the ice age. Dr. Anton Wallner, a nuclear physicist from the Australian National University in Canberra said, It's an interesting coincidence that they correspond with when the Earth cooled and moved from the Pliocene into the Pleistocene period."

The possibility of star explosions triggering transitions in the earth's natural history is not a new one - the evolution of our natural history as well as our solar system posits from this very idea. However, little scientific evidence have been found over the years - until this one.