aScientists are concerned about what happens when an empty rocket strikes another while orbiting (绕轨道飞行) the earth. 科学家关注发生了什么,当一枚空的火箭碰撞另,当围绕 (绕轨道飞行旋转) 地球时。[translate] aYou should start your essay with a brief description of the picture and then express ...