They're so powerful that astronomers call them hypernovae.

它们非常强大，天文学家称它们为超超新星。

Long ones are from hypernovae, massive stars exploding, sending out twin beams of matter and energy.

长爆发来自超新星，大质量恒星爆炸，释放出物质和能量的双束。

When you look at the duration of all the bursts detected, they divide pretty well into two groups: ones that last longer than two seconds, and come from hypernovae, and ones that are much more rapid.

当你观察检测到的所有爆发的持续时间时，会发现它们被很恰当地分为两组：一组持续时间超过2秒，来自超新星，另一组速度则更短暂。