These air rocks, not gas, they could be Metal is well, but they are hard surfaces, and sometimes they come out of the asteroid belt, get closer to the surface of the earth, or at least our atmosphere.
這些空氣岩石,不是氣體,它們可能是金屬是好的,但它們是堅硬的表面,有時它們從小行星帶出來,更接近地球表面,或至少是我們的大氣層。