| 释义 |
回归线huíguīxiàn地球上赤道南北各23°26′处的纬度圈。北边的叫北回归线,南边的叫南回归线。夏至时,太阳直射在北纬23°26′;冬至时,太阳直射在南纬23°26′。太阳直射的范围限于这两条纬线之间,来回移动,所以叫回归线。{tropic; imaginary lines of latitude drawn around the earth at 23°26′ north and south of the equator, respectively called the tropics of Cancer and Capricorn. At the Summer Solstice, the sun shines down vertically over latitude 23°26′N, and at the Winter Solstice, over latitude 23°26′S. Between the tropics the sun shines down vertically at least once a year.} |