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SciShow Space is supported by Brilliant.org.
《太空科学秀》由Brilliant.org赞助播出。
It might not always seem like it, but there’s a lot going on around us in the universe.
宇宙里一直发生着各种各种的事，虽然我们可能毫无所知。
Stars are forming, planets are being born, galaxies are being ripped apart.
恒星和行星生生不息，各星系彼此撕裂。
You name it, and it’s probably happening somewhere.
只要你想的出来，就一定在某个地方发生着某件事。
But in the middle of all this action lie ancient relics of a universe long gone.
但在这些过程中隐藏着很久以前的宇宙留下的财富，
They are red nuggets, and they’re galaxies that have done the seemingly-impossible:
即大质量宁静致密星系，这种星系可以做到看似不可能的事情：
survived billions of years of cosmic evolution without a scratch.
它们在宇宙的演变中存活了数十亿年，却毫发无损。
Finding one is like discovering a message in a bottle:
寻找这样的星系就像寻找漂流瓶传递的信息一样：
a time capsule from the early universe, delivered to our doorstep.
这是宇宙初期的时间胶囊，被送到了我们的门前。
They get their name because they’re as valuable as gold but red in color.
这种星系得名于此是因为他们价格高昂，颜色红润。
And if we can understand their secrets, they have a lot to teach us.
如果我们能明白它们蕴藏的奥秘，就能学到很多。
Astronomers today recognize two main types of galaxies: spiral and elliptical.
如今，天文学家发现了两种主要的星系：螺旋星系和椭圆星系。
Spiral galaxies are probably what popped into your mind when we started talking about galaxies.
螺旋星系很可能是我们谈论星系之时首先映入脑海的星系。
They’re pretty flat, with long, sweeping arms, like the Milky Way.
螺旋星系体态扁平，旋臂很长，覆盖面积大，跟银河很像。
They’re also full of younger, hotter stars, so their light tends to be relatively blue.
螺旋星系里到处都是年龄小、温度高的恒星，所以它们发出的光相对发蓝。
Elliptical galaxies, on the other hand, are full of older stars, so they tend to be redder and cooler.
而椭圆星系里都是年龄较大的恒星，所以颜色更红，温度更低。
They’re also much less ordered than spirals, with blobby, uniform shapes.
而且后者比前者更无序，到处都是斑点，形状统一。
Astronomers have spent much of the last century trying to sort out how galaxies end up in these two basic categories.
上个世纪，天文学家投入大量时间试图搞清楚为何星系最后会氛围这两大类。
It’s now generally accepted that spirals form first and then ellipticals are born from the collision of two or more galaxies.
普遍认可的说法是：螺旋星系率先形成，随后在一个以上的星系碰撞中产生了椭圆星系。
This helps explain why spirals are full of younger stars and ellipticals older ones.
这也帮我们理解了螺旋星系里到处都是年轻恒星，而椭圆星系里都是年纪较大恒星的原因。
It also makes sense why the collision-born elliptical galaxies are so messy in appearance.
同时，也说通了通过撞击产生的椭圆星系外观很杂乱的原因。
But with all this stuff smashing together, it’s hard to know how the lives of galaxies are “supposed” to play out, in a sense.
但从某种角度看，由于这些物质都挤在一起，所以很难得知这些星系的命运会何去何从。
If the universe were really a more peaceful place, what would things look like?
如果宇宙里少发生一些撞击事件，现在的景象又是怎样呢？
That’s where the red nuggets come in.
这就要说到大质量宁静致密星系了。
These objects were first detected by the Hubble Space Telescope in 2005, and in 2013, astronomers found more of them much closer to home.
这种星系第一次被哈勃望远镜探测到是在2005年；2013年，天文学家又发现了更多离地球更近的这种星系。
Like, only a few hundred million light-years away, versus billions.
差不多只有几亿光年远，跟几十亿光年比起来算很近了。
These galaxies are both massive and compact, meaning they have a lot of stuff inside them but they don’t take up much space.
这些星系质量超大，结构紧密，所以里面一定有很多占空间不大的物体。
Some can have more mass than ten Milky Ways, but also be ten times smaller than our galaxy.
其中有些物体的质量比银河的十倍还要大，但却是太阳系的1/10。
But what’s arguably even cooler about red nuggets is that, from what we can tell, they appear to be the ancient remnants of the first generation of elliptical galaxies.
但我们发现关于这种星系还有更酷的地方：它们看起来像第一代椭圆星系的远古残留物。
Also they’re not just ancient: Those nearby red nuggets specifically also appear to have avoided collisions since their formation, some for more than ten billion years.
而且不只是远古这一个标签：这些地球附近的大质量宁静致密星系自形成依赖就未曾发生过撞击，有些已经安然无恙地度过了100多亿年。
I mean they’ve been drifting alone through space for longer than we can really wrap our heads around.
也就是手，它们孤独地在宇宙里晃了很多年，比我们能想象的更久。
Scientists are still trying to piece together what all of this can teach us about modern galaxies, especially the elliptical ones.
科学家依然试图弄清楚这些信息对于现代星系研究来说有什么用，尤其是椭圆星系。
But for now, there is one red nugget mystery we think we’ve already solved.
但目前为止，关于大质量宁静致密星系，我们只解决了一个问题。
See, one thing that’s really notable about these objects in general is how dead they are.
有目共睹的一件事是：这种星系有一个明显的标签——呆若木鸡。
Astronomers call a galaxy dead if it’s stopped forming new stars, and from what we can tell, even the youngest red nuggets don’t seem to be making anything new.
科学家什么时候会这样描述一个星系呢？就是星系不再形成新恒星的时候。根据我们目前了解的情况，即便是刚形成没多久的大质量宁静致密星系，似乎也不再产生新恒星了。
In fact, that’s why astronomers call them red nuggets.
这就是大质量宁静致密星系得名的原因。
Without any new, blue stars to balance things out, the galaxy gets redder and redder as everything ages.
没有蓝色新恒星的抵消作用，大质量宁静致密星系的颜色随着时间的流逝会越来越红。
The good news is, a clue as to why may be hiding in plain sight: an overactive supermassive black hole.
好消息是我们发现了一条线索，该线索与可能隐藏在外表之下的东西有关，即过度活跃的超重黑洞。
Scientists believe all galaxies may have supermassive black holes at their centers like ours does.
科学家认为，所有星系都跟太阳系一样，在中心部分会有超重黑洞。
The one the Milky Way hosts weighs in at four million times the mass of the Sun, which is kind of a lot.
银河系中央的超重黑洞，其质量是太阳的400万倍，这质量非常大了。
But some of the largest black holes we’ve ever seen are at the center of red nuggets.
但我们见过的质量最大的黑洞还是在大质量宁静致密星系的中央。
The biggest are more than a thousand times more massive than the one in our galaxy.
其中质量最大的黑洞比银河系质量最大的黑洞还要大1000多倍。
So it could be a simple explanation: The huge black holes are swallowing up all the material that otherwise would create new stars!
所以可能就很容易解释了：这种超重黑洞吞没了所有能形成新恒星的物质！
Well, not really that simple.
不过，并非如此简单。
NASA’s Chandra X-ray Observatory has shown a bunch of extra heat at the center of one nearby red nugget, heat which probably comes from the black hole.
美国宇航局的钱德拉X射线天文台显示，银河系附近某大质量宁静致密星系的中央存在额外的热量，这种热量可能来自于黑洞。
The heat would’ve made gas in the galaxy too hot to easily collapse down and form new stars, a process astronomers call quenching.
这种热量会让星系中的气体温度极高，很容易分崩离析并形成新的恒星，这个过程科学家称之为熄火。
Then, over time, that gas could’ve fallen into the black hole, growing it to such massive proportions.
然后，随着时间的流逝，这种高温气体会落入黑洞之中，逐渐庞大到质量超大的比例。
This process isn’t unique to red nuggets, but they do prove it’s a mechanism that can work even after billions of years of isolation from the rest of the universe.
该过程并非大质量宁静致密星系所特有的，但确实可以证明：即便与宇宙里的其他地方脱离了数十亿年之久，该机制依然有效。
And the fact that we can figure that out at all is pretty impressive.
我们能解密此事很让人颇为振奋。
Now, we just need to investigate other mysteries, like what these ancient galaxies can tell us about the formation of the modern, massive elliptical galaxies.
现在，我们只需要研究其他的谜题就好了，比如通我们能过这些远古星系了解到多少有关现代大质量椭圆星系的形成过程。
But, right now, it’s okay just to stop and be amazed.
但就目前而言，先停下来欣赏一下这次的研究结果就可以了。
It’s a violent universe out there, and we’ve finally started to find the ultimate survivors.
宇宙里时常发生撞击事件，我们已经开始探索最终的幸存者了。
And speaking of finding things, scientists make all these discoveries using the scientific method.
说到寻找事物，科学家是用科学的方法才做出了这些发现。
And you can learn all about that at Brilliant.org.
这些发现成果在Brilliant.org上都可以找到。
I’ve talked a little before about The Scientific Process course on Brilliant and how it walks you through the process of making observations and hypotheses.
之前的节目中，我曾提到Brilliant.org上有《科学流程》的栏目，以及大家可以怎样利用这档节目来了解进行观测和假设的整个流程。
Well, once you’ve made those observations, asked questions, and hypothesized, as a scientist you need an experiment to investigate your hypothesis further.
进行了观测、发问和假设后，模拟为科学家身份的你就可以进行实验来进一步验证假设了。
And a lot of careful thought needs to go into designing an experiment.
设计实验是要花费一番心思的。
In this quiz, Experimental Design, you need to think through what questions you’re trying to answer.
在《实验设计》这项测试中， 你需要通篇思考自己要回答的问题。
You need to consider controls and variables, and at some point, you’ll probably need to reconsider your original question.
你需要思考控制和变量的问题，有时候，很有可能还需要重新思考最初的问题。
It’s an entertaining and helpful way to more deeply understand the scientific process.
能深入理解科学流程是让人享受的有益过程。
The world is complex and one thing I like about Brilliant is that their lessons don’t shy away from that, but they do keep it fun.
世界很复杂，而我喜欢Brilliant的一点就是：他们的课程并没有规避世界复杂的这一点，反而让复杂的事情变得有趣。
And right now, Brilliant is offering 20% off of their annual premium subscription to the first 200 SciShow Space viewers to sign up at brilliant.org/scishowspace.
目前，Brilliant为前200位注册brilliant.org/scishowspace的《太空科学秀》用户提供20%的年费减免。
So check it out. And if you take the experimental design quiz, let me know how you do in the comments!
心动不如行动。如果屏幕前的您已经进行过实验设计的测试了，可以将测试情况写在评论里。
Like good scientists, we can compare our results!
我们也要像优秀的科学家一样对比结果！
