Scientists have found evidence of two separate supernova events in the last 7.5 million years that showered the Earth with radioactive debris like iron-60. These events were traced back to the Scorpius-Centaurus association of young, massive stars about 300-400 light-years away.
While the amount of supernova material that reaches Earth is tiny compared to the total ejecta, it indicates that our planet has been bombarded by radioactive ashes from exploding stars thousands of times over its history.
The most recent known nearby supernova event may have been visible in the sky to early human ancestors like Australopithecus afarensis, appearing as a bright star or "guest star" in the sky
hammock|1 year ago
Scientists have found evidence of two separate supernova events in the last 7.5 million years that showered the Earth with radioactive debris like iron-60. These events were traced back to the Scorpius-Centaurus association of young, massive stars about 300-400 light-years away.
While the amount of supernova material that reaches Earth is tiny compared to the total ejecta, it indicates that our planet has been bombarded by radioactive ashes from exploding stars thousands of times over its history.
The most recent known nearby supernova event may have been visible in the sky to early human ancestors like Australopithecus afarensis, appearing as a bright star or "guest star" in the sky
bell-cot|1 year ago
I was a subscriber from ~1972 to ~2000, and kept my old issues. Folks have told me that even in '76, SciAm had been heading down for a long time.
unknown|1 year ago
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