精密度测量器一种仪器，用于比较物体的可度量性质，例如按标准度量它的形状、颜色或亮度 Any of various instruments for comparing a measured property of an object, such as its shape, color, or brightness, with a standard.
星星光亮度不同。 Stars vary in brightness.
逐渐消失在亮度、响度或精力上逐渐减弱直至全部消失的活动或例子 The act or an instance of gradually diminishing in brightness, loudness, or strength until actual disappearance occurs.
