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.

簡儀爲元代(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。