The folks at the Sloan Digital Sky Survey told us last fall -- they're making the first map of the universe, three-dimensional map of the universe -- that there are probably 700,000 asteroids between Mars and Jupiter that are a half a mile big or bigger.
斯隆数字巡天勘探中心人员去年秋季告诉我们—— 他们正在绘制宇宙的第一张三维地图， 其中火星和木星之间就有70万个小行星 大概有半英里甚至更大。