blue shift

blue-shift的词性：
n.（名词）

1. A decrease in the wavelength of radiation emitted by an approaching celestial body as a consequence of the Doppler effect.
蓝移：飞近的天体发射出的幅射波长之减小，是杜普勒效应的结果

blue-shift的词源：

2. [From the fact that the shorter wavelengths of light are at the blue end of the visible spectrum]
[源于在可看见的光谱中波长较短的光线是在可见光谱一端的事实]