Scientists said that the culprit responsible for so many deaths may not be local. In fact, it may not have even come from our solar system.
Rather, a new study led by astronomer Brian Fields of the University of Illinois, Urbana-Champagne suggests that this great extinguisher of life on Earth may be a distant and completely alien phenomenon – a dying star, across the galaxy, many light -The year. Away from our own remote planet.
Sometimes, people who die on a large scale, such as the Late Devonian extinction, are believed to be triggered exclusively by terrestrial causes: for example a devastating volcanic eruption, which bites the planet into lifelessness.
Or, it could be a deadly visitor stopping from outside the city – an asteroid collision, the way dinosaurs were taken out. Death from space, however, may eventually come from far more remote locations.
“The broad message of our study is that life on Earth does not exist in isolation,” Fields says.
“We are citizens of a larger universe, and the universe interferes with our lives – often imperfectly, but sometimes brutally.”
In his new work, Fields and his team explore the possibility that the dramatic drop in ozone levels coincides with the Late Devonian extinction, perhaps not a result of an episode of volcanism or global warming.
Instead, they suggest that it is possible that the biodiversity crisis exposed in the geological record may be due to astrological sources, predicting that the impact of radiation from a supernova (or multiple) about 65 light-years from Earth. That can destroy our planet’s ozone. Such devastating effects.
This may be the first time such an explanation has been put forward for Late Devonian extinction, but scientists have long considered the potentially fatal consequences of near-Earth supernovae in such a context.
The fantasy that the supernova may have begun to go into mass extinction in the 1950s. In recent times, researchers have debated the estimated ‘kill distance’ (with estimates between 25 and 50 million light years) of these explosive events.
In their new estimates, however, Fields and his co-authors propose that the detonation of stars from far away on Earth, through a possible combination of immediate and long-lived effects, can have a detrimental effect on life.
“Supernovas (SNe) ions are quick sources of photons: extreme UV, X-rays, and gamma rays,” the researchers point out in their paper.
“Over a longer period of time, the explosion hits the surrounding gas, causing a shock that induces particle acceleration. In this way, SNE produces cosmic rays, that is, atomic nuclei would accelerate to higher energies. Is. These charged particles are magnetically confined inside the SN residue. And are expected to bathe the Earth for ~ 100 ky [approximately 100,000 years]. ”
These cosmic rays, the researchers argue, may be strong enough to destroy the ozone layer and cause long-lasting radiation damage to life-forms inside the Earth’s biosphere – the diversity of ancient plant spores. And the deformity has nearly the same disadvantages of both. The deep reef of the Devonian – Carboniferous border was laid about 359 million years ago.
Of course, this is a hypothesis for now. Currently, we have no evidence that can confirm a distant supernova (or supernova) that was the cause of Late Devonian extinction. But we can almost find something good as proof.
In recent years, scientists investigating the possibility of near-Earth supernovae as the basis of mass extinction have looked for traces of ancient radioactive isotopes that could have accumulated on Earth only by exploding stars.
In particular, an isotope in iron-60 has been the focus of much research, and has been found in many places on Earth.
However in the context of Late Devonian extinction, other isotopes would strongly indicate the extinction supernova hypothesis put forward by Fields and his team: plutonium-244 and samarium-144.
“Neither of these isotopes occurs naturally on Earth today, and Zhengyi Liu, a co-author and astronomy student at the University of Illinois at Urbana-Champagne, explains,” The only way they can reach here is through a cosmic explosion Huh.
In other words, if plutonium-244 and samarium-144 and buried in the Devonian-Carboniferous range can be found, the researchers say that we would basically have our smoking gun: the interstellar evidence that strongly convinces the dying star to be a Refers to as the trigger behind. Earth’s worst ever to die.
And we will never look at the sky the same way again.
The findings are stated in PNAS.