STIS spectrum showing Interaction regions

SN 1987A was a supernova within the Large Magellanic Cloud, a companion dwarf galaxy of the Milky Way. Observations made several months after the supernova showed a ring surrounding the remnants of the progenitor stars. This ring consists of material from the stellar wind of the star which was ionized by the explosion of the supernova. In 2001 the expanding material from the supernova collided with this ionized gas, whereby the material was heated up.