NASA, ESA, J. Hester, A. Loll (ASU)
Supernovas may have affected the Earth’s climate in the last 40,000 years. Tree-ring data suggests supernovas caused spikes in radiocarbon. Could the next nearby supernova cause a collapse of civilization?
Dendrochronology is a fancy word for tree-ring dating, where the age of a tree can be determined by the number of growth rings across its trunk. But there’s a lot more to learn from looking at a tree’s rings than simply its age.
Like fingerprints, tree rings give scientists clues to what the world was like when a tree was alive. By studying tree rings, we can determine when the tree lived, the climatic conditions through which it lived, and possibly, what was happening in the universe at the time.
In a new study published in the International Journal of Astrobiology, geoscientist Robert Brakenridge, of the University of Colorado, suggests a number of supernovas may have left their mark on life on Earth over the last 40,000 years. By poring through countless tree ring records and matching them to known supernova events, Brakenridge discovered that of the eight recent supernovas he studied, each one seemed to leave their mark on trees.
The alarming part? Four of those supernovas may have significantly disrupted Earth’s climate, leading scientists to wonder what the next supernova event might mean for civilization.
How to Get Started in Astronomy
Supernovas are brilliant explosions caused by the deaths of massive stars. They’re the most massive and energetic explosions known to science, sometimes shining brighter than the combined light of their galaxies. The overwhelming energy released in such an explosion has caused scientists to worry that a
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