The beacon of Taurus
THE DYING STAR HAD ABOUT 10 TIMES the mass of our Sun and had just lost the ability to fuse elements in its core. Without the outward pressure of fusion to hold back its own crushing gravity, the inner core collapsed within seconds into a 20-kilometre-wide sphere of neutrons. The outer core of the star immediately crashed onto this abruptly smaller and superdense core at 23% the speed of light. A titanic shock wave explosively rebounded off the star’s neutron core, completely disrupting its outer layers in a star-shattering Type II supernova. The intensely sudden and cataclysmic death of the star was briefly brighter than the entire Milky Way galaxy.
Around 6,500 years later Chinese astronomers saw a brilliant ‘guest star’ in the pre-dawn sky near Zeta (ζ) Tauri on July 4, 1054. For 23 days it was visible in broad daylight and at night it had a reddish-white colour. It took more than a year and a half for it to gradually fade from sight.
Some 700 years after that, the still-expanding debris nebula of the supernova inspired Charles Messier to start his catalogue of things that looked like comets but didn’t move relative to the stars. Althought it had been discovered 27 years earlier by John Bevis, Messier independently found the
