A tree ring can trigger the effects of distant supernovae on Earth

According to new research by Colorado Boulder geologist Robert Brackenridge, thousands of light-years of energy eruptions from Earth could leave traces in our planet’s biology and geology.

The study, published this month International Journal Astrobiology, Investigating some of the most violent events in the known universe, the effects of supernovae. In just a few months, even one of these eruptions could release as much energy as the sun throughout its lifetime. They are bright but really bright.

“We see supernovae all the time in other galaxies,” said Breckenridge, a senior research associate at the Arctic and Alpine Research Institute at CUU Boulder. “Through the telescope, the galaxy is a bit of a misty space. Then, all of a sudden, a star appears and can be as bright as the rest of the galaxy.”

A very close supernova would be able to wipe human civilization off the face of the earth. But despite the distance, these eruptions could still take a long time, Breckenridge said, to bathe our planet in dangerous radiation and damage its protective ozone layer.

To study those potential effects, Brecknridge searched through the planet’s tree ring records for fingerprints of these distant, cosmic explosions. Its findings suggest that supernovae, which are relatively close in the last 2,000,000 years, could theoretically cause at least four disruptions in the Earth’s atmosphere.

The results are far from decisive, but they do give the longing-for sign that, when life comes to a standstill on Earth, what happens in space does not always stay in space.

“These are extreme events, and their potential effects seem to match the tree ring records,” Breckenridge said.

Radiocarbon spikes

His research is bound up in the case of a strange atom. Breckenridge explained that carbon-14, also known as radiocarbon, is a carbon isotope that occurs only in small amounts on Earth. It’s not even from here. Radiocarbon is formed when cosmic rays from space bombard our planet’s atmosphere on an almost constant basis.

“There’s usually a fixed amount year after year,” Breckenridge said. “Trees take in carbon dioxide and some of that carbon will be radiocarbon.”

Sometimes, however, the amount of radiocarbon that the tree picks up is not stable. Scientists have found a handful of cases in which the concentration of this isotope inside a tree increases-suddenly and for no apparent reason. Many scientists have speculated that these spikes, which have been going on for many years, may have been caused by solar flares or huge emissions of energy from the sun’s surface.

Breckenridge and several other researchers have their eye on events away from home.

“We’re looking at terrestrial events that request clarification,” Breckenridge said. “There are really only two possibilities: a solar flare or a supernova. I think the supernova hypothesis has been rejected very quickly.”

Keep the areca

He noted that scientists have noted supernovae in other galaxies that have produced very large amounts of gamma radiation – the same type of radiation that can stimulate the formation of radiocarbon molecules on Earth. While these isotopes are not dangerous on their own, but their rising levels could signal that distant supernova energy rays have traveled thousands of light-years to our planet.

To test the hypothesis, Breckenridge turned to the past. He assembled a list of supernovae that have come closer than Earth in the last 40,000 years. Scientists can study these phenomena by observing the nebulae they have left behind. He then compared the estimated age of those galaxy fireworks with the tree ring record on the ground.

They found that the study found that out of eight nearby supernovae, all seemed to be associated with unknown spikes in the Earth’s radiocarbon record. He considers these four particularly promising candidates. Take the case of the former star in the Vine constellation. These celestial bodies, which at one time sat about 815 thousand years from Earth, went into a supernova about 13,000 years ago. Long after that, the level of radiocarbon on Earth increased by about 3% – a surprising increase.

The findings in this case are nowhere near a smoking gun or a star. Scientists still have difficulty dating past supernovae, so the timing of the vine eruption is uncertain with a possible error of 1,500 years. It is also not clear at the time what the effects of such a disruption might be for plants and animals on Earth. But Breckenridge believes the question is appropriate for further research.

“When I look at the terrestrial record and I say ‘My God, the predicted and modeling effect appears there.’

He hopes that humanity will not soon see those effects for itself. Some astronomers believe that they have taken indications that Batalizius, the star of the constellation Orion, may be on the verge of collapsing into a supernova. And it is only 642.5 light-years from Earth, which is much closer than a vine.

“We can only hope that this is not going to happen, because the battles are really close,” he said.