... Supernova 1987A (LMC) . ... Type I: thermonuclear runaway in a red-dwarf/white-dwarf binary . ... At present, such an event is unlikely, since the nearest potential Type I supernova is at least 50 light years distant, and the nearest Type II ~1500 light years away (in Orion). However, the Sun orbits the Galactic Centre once every 100 million years; every ~30 million years, or so, it passes through a Galactic spiral arm - major sites for star formation, regions with many, short-lived massive stars. ...