From Science Daily:
ScienceDaily (Dec. 4, 2008) — Astronomers have used light echoes as a time machine to unearth secrets of one of the most influential events in the history of astronomy –a stellar explosion witnessed on Earth more than 400 years ago.
By using a Galactic cloud as interstellar “mirror” an international team led by Oliver Krause of the Max Planck Institute for Astronomy in Germany has now re-analysed the same light seen on Earth in the 16th century and have, for the first time, determined the exact type of the explosion that happened. Calar Alto Observatory has contributed to this discovery and these results were published in the scientific journal Nature, 4th December 2008 issue.
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