This big splat is a low-velocity collision," said study co-author Erik Asphaug, a planetary scientist at the University of California, Santa Cruz.

也没办法避免……双月碰撞属于低速碰撞，”圣克鲁兹州加利福尼亚大学天体科学家兼本次研究论文撰写者埃里克·埃斯帕格说。