超新星的橄榄形揭示爆炸如何点燃

A supernova’s oblong shape hints at how the blasts ignite For most of their lives, stars at least eight times as massive as the sun generate an outward pressure through the fusion of hy- drogen and helium atoms in their core, counteracting gravity. But once these stars run out of fuel, that pressure disappears and the core collapses. The upper layers of the star follow suit, and as they hit the core, they create a rebounding shock wave. The shock wave splits the star’s surface and releases an immense amount of energy and light, which we see as a supernova. How exactly the shock wave starts is a long-standing question. …