The Vela Supernova Remnant Expands.

The explosion is over but the consequences continue. About eleven thousand years ago a star in the constellation of Vela exploded, creating a strange point of light briefly visible to humans living near the beginning of recorded history . The outer layers of the star crashed into the interstellar medium , driving a shock wave that is still visible today . Different colors in the complex, right moving shock, pictured on the left , represent different energies of impact of the shock front . The star on the left appears by chance in the foreground, and the long diagonal line is also unrelated. Remaining at the center of the Vela Supernova Remnant is a pulsar , a star as dense as nuclear matter that completely rotates more than ten times in a single second.