Such a giant impact is unsurprising given the amount of material careening around the early solar system, and Earth-like planets in other systems may have moons, too.

• 由于早期的太阳系充斥著大量四处游走的物质，这样的巨大撞击并不奇怪，且其他系统里像地球般的行星，也可能拥有月球。