There are about 100,000 balls of ice and rock -- comets, really -- out there, that are 50 miles in diameter or more, and they regularly take a little spin, in towards the Sun and pass reasonably close to us.
約10万もの球形の氷や岩が存在し 直径80km級の彗星はその外側にあります それらは規則的に少し回転します 太陽に向かって 地球の比較的近くを通過します