常見例句雙語例句The low-latitude meridian circle is requested to determine the transit time and the apparent zenith distance simultaneously when a star is passing across the meridian of the instrument;為了滿足低緯子午環(huán)絕對測定方法的要求,即在子午方向同時測定天體中天時刻和天頂距;The first meridian circle of China has been installed at CSAO in April 1990. This horizontal reflecting transit circle with 240ram effective aperture is developed by CSAO, NAIF and CUO.我國第一架水平子午環(huán),其有效口徑在世界上為最大,于1990年4月在陜西天文臺臨時觀測室安裝就緒。 返回 meridian transit