雙語科技百科(天文) 第13期:簡儀
Abridged Armilla
簡儀The Abridged or simplified Armilla was invented in 1276 by Guo Shoujing (1231一1316),an astronomer in the Yuan Dynasty(1271一1368),for measuring positions of celestial bodies.
簡儀為元代(1271一1368)天文學家郭守敬(1231一1316)於公元1276年創制的一種測量天體位置的儀器。The apparatus is simpler than the armillay sphere in terms of structure and application,and it gives a panorama of the celes-tial sphere except the part around Polaris,so it is called Abridged Armilla.
該儀器的結構和使用都比渾儀簡單,而且除北極星附近以外,整個天空一覽無餘,故稱簡儀。
The primary structure of Abridged Armilla contains two large rings that are per-pendicular to each other, of which one is parallel with the equatorial plane and is accordingly called“equatorial ring;,
簡儀的主要裝置是由兩個互相垂直的大圓環組成,其中的一個環面平行於地球赤道面,叫做“赤道環”;and the other is a double-ring which is per-pendicular to the center of the equatorial ring,revolving around a metallic shaft,and is called“right ascension double-ring.
另一個是直立在赤道環中心的雙環,能繞一根金屬軸轉動,叫做“赤經雙環”。The double-ring holds within itself a sighting tube with crosshairs,which equals to a monocular and revolves around the center of the right ascension double-ring.
雙環中間夾着一根裝有十字絲裝置的窺管,相當於單鏡筒望遠鏡,能繞赤經雙環的中心轉動。During observation,the sighting tube is targeted at a certain star, thus the positional value can be read out at the dials of the equatorial ring and the right ascension double-ring.
觀測時,將窺管對準某顆待測星,然後在赤道環和赤經雙環的刻度盤上直接讀出這顆星星的位置值。Two stands are supportingthe metallic shaft that exactly directs at the south and the north,bracing the entire observing unit to a position in which the north part is higher than the south part.
有兩個支架託着正南北方向的金屬軸,支撐着整個觀測裝置,使這個裝置保持着北高南低的形狀。The equatorial mounting,invented by the Chinese,was somewhat 500 years earli-er than like devices createdin Europe
這是我國首先發明的赤道裝置,要比歐洲人使用的赤道裝置早500年左右。