They're light because of the effects of cosmological red shift.

他们质量很轻，这是因为宇宙红移影响。

This is very similar to the Doppler redshift I've talked about in earlier episodes, and is called a gravitational redshift.

这和我之前讲过多普勒红移非常相似，被称为引力红移。

That's just what galaxy redshifts are telling us.

这就是系红移告诉我们。

Remember, redshift stretches the wavelength of light.

记住，红移延伸了光波长。

It was as if the predictions based on the redshifts were underestimating the distances to the exploding stars.

似乎基于红移估了到爆炸恒距离。

And as distant stars move further away from us, the wavelength of their light increases and shifts towards red.

当遥远恒离我们越来越远时，们光波波长逐渐增加，并发会生红移现象。

Then those can be compared to the supernovae redshifts, which is a different way of getting their distance.

然后可以将之与超红移相比较，这是一种不同距离量方法。

They are shifted all the way into the infrared, so we're only really able to observe those galaxies by looking infrared.

红移结果是进入红外线，所以只能通过红外线来观这些系。

Out away from earth you drift, This is known from your redshift.

你远离地球漂流， 这是从你红移中得知。

When light loses energy its wavelength gets longer — that's what cosmological redshift is.

当光失去能量，波长会变长，这就是宇宙学红移。

But its wavelength kept stretching out, redshifting until it could only be detected as microwave radiation.

但波长不断延伸，红移， 直到只能作为微波辐射被检到。

When he examined their spectra, he saw that almost all of them were highly redshifted.

当他检查们光谱时，他发现几乎所有原子都有高度红移。

And this trend of distant galaxies moving away from us, and from one another, is called cosmological redshift.

这种遥远系 远离我们、彼此远离趋势被称为 宇宙学红移。

I wanted to explore the whole universe, not just whatever I can see, you know, before the redshift kicks in.

我想探索整个宇宙，而不仅仅是我能看到一切， 你知道，在红移开始之前。

Using the idea of lookback time, they could predict how far away it would be from us, and therefore calculate its redshift.

利用回溯时间概念，他们可以离我们有多远，从而计算红移。

We discussed redshift and used Hubble’s Law to calculate how much certain parts of the universe are expanding away from us.

我们讨论了红移并使用哈勃定律来计算宇宙某些部分正在向远离我们方向膨胀。

On their merry-go-round path, one undergoes a redshift as it moves away, and the other has a blue shift as it moves toward us.

在们旋转轨道上，一颗在远离地球时发生红移，另一颗在靠近地球时发生蓝移。

We discussed redshift and used Hubble's Law to calculate how much certain parts of the universe are expanding away from us.

我们讨论了红移，并使用哈勃 定律来计算 宇宙某些部分正在远离我们膨胀程度。

There is also the problem that access to telescopes is always at a premium and historically measuring red shifts has been notably costly in telescope time.

使用天文望远镜总是代价很高，在历史上，量红移要长时间使用天文望远镜，令人注目地花钱很多。

When you're right at the event horizon, just when an outside observer would see your clock stop, they'd also see the light coming from you infinitely redshift!

若你正好在事件视界之中，当外部观察者看到你时钟停止时，他们也会看到来自你无限红移光！