Life on earth may have benefited from the explosion of massive stars, according to Danish physicist Dr. Henrik Svensmark of the Technical University of Denmark.
When massive stars reach the end of their lives they explode as supernovae and in the process release vast amounts high-energy charged particles known as galactic cosmic rays (GCR). If a supernova is close enough to earth these GCR may reach and have a direct impact on the atmosphere of the Earth.
Dr. Svensmark conducted analyses that looked back through 500 million years of geological and astronomical data to determine the rate at which these explosions occurred and whether they were related to life on earth. His findings show that whenever there was a high chance for galactic cosmic rays to reach the earth, life thrived. "The biosphere seems to contain a reflection of the sky, in that the evolution of life mirrors the evolution of a galaxy," said Dr. Svensmark in a statement to the press.
"Evidence of nearby supernovae affecting life on Earth" (DOI: 10.1111/j.1365-2966.2012.20953.x)