Hé / shì / yàn / de / Dì miàn Líng diǎn / tōng / cháng / shì / bào / zhà / zhōng / xīn / de / zhèng / xià / fāng / wèi / zhì

核试验的地面零点通常是爆炸中心的正下方位置。

The ground zero of a nuclear test is usually the position directly below the explosion center.