During the 1987 February 23rd night, astronomers observed the explosion of a supernova in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. The exploded star was the blue supergiant Sanduleak (Sk) − 69o202, with a mass of 20 solar masses, and its explosion produced the supernova remnant SN 1987A. From that moment, SN 1987A was observed with
The life cycle of very massive stars ends in supernovae explosions. During these violent phenomena, an amount of energy similar to that produced by the Sun during its entire lifetime,more than 10 billion years long, is released in few seconds. Besides, the atmosphere of the exploding star (the progenitor star) is ejected with a velocity in excess of 1000 km/sec.
In vari racconti per bambini le stelle sono descritte o paragonate ad esseri viventi. Una visione certamente romantica e poco scientifica, che pero’ potrebbe celare qualche verita’. Le stelle hanno infatti un loro ciclo vitale, un po’ come gli esseri viventi. Esse infatti nascono da enormi nubi di gas e polveri (processo di formazione stellare), attraversano una fase di puberta’
