These rocks are believed to be the result of an asteroidal prang that happened many millions of years ago and left a crater 460km across , which dominates vesta 's southern hemisphere .

据科学家们认为，这些岩石是发生在好几百万年前的一次小行星碰撞的结果，而且留下了一个独占灶神星南半球460公里宽的陨石坑。