Supernovas may have affected the Earth’s climate in the last 40,000 years. Tree-ring data suggests supernovas caused spikes in radiocarbon.

Ancient supernovas may have blasted Earth with powerful radiation, causing dramatic changes in our climate, and could do so again, posing a threat to life.

Luckily for Earth, these supernovas are well outside the calculated kill-distance of about 8 parsecs (or around 26 light-years), where such an explosion would be bad news for life.

The calculations suggested 2.5 supernovas might affect Earth in some way every 1 billion years, equating to one or two in the past 500 million years during which life evolved on the planet.

Two ancient supernovas exploding 300 light-years away from Earth most likely bludgeoned early life on Earth with intense amounts of radiation, according to new research published Monday in The ...

However, supernovas can also be deadly. If one explodes within 65 light-years of Earth, it could strip away the ozone layer. This would expose the planet to harmful radiation and acid rain.

Supernovas may have triggered ancient ice ages, wiping out 60–70% of Earth’s species: Study A supernova — the explosive death of a massive star — can leave behind a black hole or neutron star.

The calculations suggested that 2.5 supernovas might affect Earth in some way every 1 billion years, equating to one or two in the past 500 million years during which life evolved on the planet.

"Tree rings may hold clues to impacts of distant supernovas on Earth." ScienceDaily. ScienceDaily, 11 November 2020. <www.sciencedaily.com / releases / 2020 / 11 / 201111144400.htm>.