SN 1987A Nebula

SN 1987A was a Type II supernova that occurred in the Large Magellanic Cloud, a satellite galaxy of the Milky Way, in February 1987. It was the closest observed supernova since the invention of the telescope, providing astronomers with an unprecedented opportunity to study a stellar explosion.

Because it was located only about 168,000 light-years away, SN 1987A allowed scientists to study the mechanics of a supernova in real-time. It famously provided astrophysicists with the first direct opportunity to detect neutrinos from a supernova blast.

The SN 1987A remnant is famously surrounded by a set of three glowing gas rings, which were ejected by the progenitor star thousands of years before the explosion. Over the decades, the expanding shockwave from the supernova has violently collided with the inner ring, heating the gas and causing it to brightly illuminate.

The supernova was caused by the core-collapse of a massive blue supergiant star, which was previously cataloged as Sanduleak -69° 202. Astronomers were initially surprised by this, as blue supergiants were not widely expected to go supernova in standard theoretical models of stellar evolution.