bolide

1. More and more evidences show that the volcanism might be the most likely cause of this event, although others triggers, such as sea level change, oceanic anoxia, bolide impact, methane gas hydrates, have not been excluded.
   越来越多的证据显示火山作用是引起这次生物集群绝灭最可能的原因，虽然其他的因素，如海平面变化，海洋缺氧，地外行星撞击，甲烷及其水合物释放等，还没有排除。

noun

1. an especially luminous meteor (sometimes exploding)

   Synonym:    fireball