science · 09 October 1604 · 421 years ago
The supernova which becomes known as Kepler's Supernova (SN 1604) is first observed from northern Italy. From 17 October, Johannes Kepler begins a year's observation of it from Prague. As of 2006, this is the last supernova to be observed in the Milky Way, and the last visible by the naked eye until 1987.