That means that its light will undergo a Doppler shift, and that can be detected.

意味着它的光会经历多普勒，并且被探测到。

Another way is to measure the Doppler shift in a star's light due to reflexive motion as the planet orbits.

另一种方法是测量恒星光线的多普勒，种是由行星绕轨道运行时的自反运动引起的。

If we know the planets' mass from the star's Doppler shift, we can use the planet's size to calculate its density.

如果我们通过恒星的多普勒知道行星的质量，我们用行星的大小来计算它的密度。

The stars Slipher looked at showed unmistakable signs of a Doppler shift, the same mechanism behind that distinctive stretched-out yee-yummm sound cars make as they flash past on a racetrack.

斯莱弗发现，些恒星明确显示出一种多普勒的迹象，跟赛车场上飞驰而过的汽车发出的那种连贯而又特有的“嚓——嗖”的声音属于同一机制。

While we may not see that motion directly, if we take spectra of their light, breaking it up into individual narrow colors, we can see the Doppler shift in their spectra.

虽然我们能无法直接看到种运动，但如果我们把它们的光谱分解成单独的窄色，我们看到在它们光谱中的多普勒。

Star forming gas clouds emit a very narrow wavelength range of radio waves, and this could be used to measure their Doppler shift, how quickly they were moving toward or away from us.

恒星形成气体云发射出波长范围非常窄的无线电波，用来测量它们的多普勒，即它们向我们动或远离我们的速度。