An area of the celestial sphere occupied by one of the88 recognized constellations. 星座区域天球上88个已被确认的星座中的一个所占据的区域
A polar projection of half or more of the celestial sphere on a chart equipped with an adjustable overlay to show the stars visible at a particular time and place. 星座一览图天体球的一半或多半在平面图上的极投影图,这种图具有可调节的遮蔽物以显示在给定时刻和位置可见的恒星
A point on the celestial sphere directly below the observer, diametrically opposite the zenith. 天底天球上,在观测者垂直向下的一点,与天顶完全相对