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Last week, two papers published in the journal Science unveiled some huge news in the world of astrophysics, featuring the tiniest particles in the universe.
上周，《科学》期刊上发表了两篇论文，其中公布了天体物理学里几条令世界震惊的新闻，这些新闻都跟宇宙里最小大的一些分子有关。
More than 1000 authors from nearly 20 research institutions spanning the globe announced that they've likely identified the very first astrophysical source of high-energy neutrinos.
来自全球近20个研究所的1000多名科学家宣布，他们很可能发现了高能中微子从天体物理学角度看的第一个源头。
This is the first evidence toward solving a century-old mystery about the source of certain cosmic rays.
这是第一份证据，有助于我们揭开有关特定宇宙射线源头的世纪谜题。
And some are even calling it the dawn of a new era in astronomy…
有些人甚至将这份证据称为天文学新时期的黎明。
but we'll have to see about that.
但这一点还有待商榷……
Now Cosmic rays are actually particles, and they constantly rain down on Earth from a variety of outer space sources.
先来说说宇宙射线：它实际上是微粒，会四面八方不断涌向地球。
Most come from the Sun, but a few super high energy ones come from places outside the galaxy.
大多数微粒都来自太阳，但还有一部分超高能微粒来自太阳系外。
Until now, though, astronomers haven't had evidence to show exactly what objects are launching them in our direction.
不过，目前为止，天文学家还没有证据可以证明是什么物体放射出了这些微粒。
Hypotheses have included violent events like supernovas, colliding galaxies, or merging black holes, but it's really hard to identify a source.
人们进行了一些假设，比如发生了一些激烈的事件：超新星形成、星系相撞、黑洞互相合并等，但要确定是某个源头还有很大的难度。
That's because cosmic particles are electrically charged, so they don't travel in straight lines from where they were born to our detectors.
这是因为宇宙微粒都带电荷，所以在出生地到我们设置的探测器之间的路程里，它们不会沿直线移动。
Their trajectories are affected by any kind of magnetic field.
它们的轨迹受到了某种磁场的影响。
And it's not like the universe has a shortage of magnetic fields.
宇宙里的磁场可不少。
So instead, researchers have been trying to understand cosmic rays by looking at another kind of particle called neutrinos.
所以，研究人员理解宇宙射线是通过观测另一种名为中微子的宇宙微粒来进行的。
Specifically, high-energy ones, or those with energy values too high to be produced by any device on Earth.
准确来说，是高能粒子，这是一种能量值相当高的粒子，无法通过地球上的任何装置来产生。
These neutrinos are created when high-energy cosmic rays interact with things like nearby gas.
中微子产生的条件是：高能宇宙射线与附近的气体发生反应。
And because they don't have an electric charge, they aren't affected by magnetic fields.
而且由于中微子不带电荷，所以不会受到磁场的影响。
So if astronomers could detect some of these neutrinos on Earth, they could trace them back to their source, and pinpoint what was creating the original cosmic rays.
所以，如果天文学家能在地球上探测到中微子，那么它们就能找到中微子的源头，并确定产生这种原始宇宙射线的来源是什么。
Mystery solved.
现在谜题解开了。
Then again, detecting these particles isn't exactly easy, either.
但我们又遇到了同样的问题：很难探测到这些粒子。
They're by far and away the least massive particles known to physics.
它们是物理学迄今为止发现的质量最小的粒子。
They're basically cosmic ghosts.
它们就像宇宙里看不见摸不着的风一样。
Like, every second, trillions of them are passing through your body and they can stream through entire planets as if there's nothing there.
举个例子，每秒钟都会有数万亿中微子经过你的身旁，即便它们穿过所有行星，也仿佛从未来过一样。
But back in 2017, researchers struck gold.
但2017年的时候，有一些研究人员有了重要发现。
On September 22, a single high-energy neutrino interacted with the IceCube Neutrino Observatory down in Antarctica.
9月22日，一颗单独的高能中微子与南极洲的中微子观测站发生了相互作用。
One of this detector's main jobs is to track down these kind of particles, and to do it, it uses over 5000 sensors arranged in a 3-dimensional grid.
该观测站的其中一项主要任务就是追踪这些中微子，而为了实现这个目标，该观测站在一个三维的电网中部署了5000多个感应器。
It's also buried more than 1.4 kilometers beneath the icy surface to avoid interference.
为了避免干扰，观测站还建在了冰层之下的1400多米处。
When high-energy neutrinos collide with the atoms in or near the detector, they make secondary charged particles, which produce blue light that's detected by IceCube's grid.
当高能中微子与观测站里面或者附近的原子发生撞击时，会产生二次带电粒子，而二次带电粒子产生的蓝光可以被中微子观测站探测到。
But the events are rare.
但这种情况的概率是很小的。
Since 2013, the experiment has only detected a few dozen high-energy neutrinos, and they've appeared to be arriving from random directions.
自2013年以来，该实验只探测到了几十个高能中微子，而且这些中微子来自四面八方。
So astronomers weren't able to pin down any obvious sources.
所以天文学家无法找到明显的来源定位。
But this time was different.
但这次情况有所不同。
Astronomers were able to narrow this neutrino's origin in space to 1 degree in the sky off the left shoulder of the constellation Orion.
天文学家可以将中微子的定位缩小到猎户星座左肩的1°。
It doesn't sound like much, but that's about twice the size of the Moon as seen from Earth.
虽然1°听起来不多，但已经是从地球上看月莲各大小的近两倍了。
And in that area of space, teams found 637 objects that might be responsible for the IceCube neutrino.
而且在这个区域，一些小组发现了637个物体，这些物体可能是在中微子观测站产生中微子的原因。
Still, with enough data matching, and time spent hunting, follow-up observations were able to narrow all that down to a single source:
有了充分的数据匹配，辅以大量的时间，后续的观测将对象缩小到了一个单个的源头：
a flaring blazar about 4 billion light-years from Earth nicknamed “the Texas source.”
一个闪闪发光的耀变体，距离地球有近40亿光年的距离，它的名字是“德克萨斯源”。
Because its full name is TXS 0506+056, and no one wants to mess with that.
其学名是TXS 0506+056，没人愿意把这名字从头读到尾。
Blazars are a special kind of quasar, and they're some of the brightest objects in the entire universe.
耀变体是一种特殊的类星体，是宇宙里最耀眼的物体之一。
They're also called blazars, which is great.
叫耀变体实在是很贴切。
Quasars in general are the central cores of certain galaxies, ones housing a supermassive black hole that's actively gobbling up matter.
类星体总体而言是星系的中央内核，其中住着一个特大质量黑洞，不断吸收物质。
As that matter spirals down into the belly of the beast, it emits a lot of radiation, so much that the core can outshine the light of all the stars in the galaxy a thousand-fold.
吸收的物质以旋涡状的方式进入黑洞深处，同时释放大量辐射，由于辐射强度很大，所以其内核的亮度要比整个星系的恒星加起来还要亮一千倍。
Some quasars also have magnetic fields that accelerate particles away at near light-speeds in what are called relativistic jets.
有些类型题也有磁场，它们的磁场可以加速粒子以近光速的速度脱离，这就是相对论射流。
And blazars are those that have a jet pointed close to straight at us.
而耀变体发出的射流离我们就很近。
Now, it looks like they're also one confirmed source of cosmic rays. Finally!
现在看来，它们也是经过确认的宇宙射线来源了。所以终于有进展了！
Thanks to work by hundreds of scientists, we were somehow able to track one tiny particle from a detector in Antarctica all the way across the universe to a specific blazar.
感谢上百位科学家的辛勤工作，我们总算能通过南极洲的一个观测站来追踪极其微小的料子了，寻着它穿越宇宙来到特定的耀变体上。
Which is amazing.
这就很神奇了。
Of course, there is a chance that the neutrino didn't actually come from some blazar's cosmic rays.
当然，有可能中微子并非来自某个耀变体的宇宙射线。
But you can make a good case that it did.
但我们姑且这样假设。
When astronomers looked back at older IceCube data, they did find evidence that other neutrinos came from the same place, during events when the blazar was ‘acting up' so to speak.
天文学家回顾中微子观测站的旧数据时，确实发现了一些证据表明其他的中微子来自同一个地方，中微子活跃的时期也是耀变体活跃的时期。
Stuff like emitting extra bursts of gamma rays.
有的物质还会发射出伽马射线。
A statistical analysis also showed that the chance that the events are unrelated is about 1 in 5000.
统计分析显示，这些事件不相关的可能性大约是1/5000。
Those are pretty great odds, but it's also not impossible that we're wrong.
确实也有很大的可能性，但我们的猜想也不是不可能。
So this massive team of astronomers has to keep hunting.
所以天文学家们还要继续探索追寻。
So far, though, these results show the possibilities of what the field calls multimessenger astronomy, using not just light, but neutrinos or even gravitational waves to study the same object.
目前为止，结果显示，用多信使天文学的方法来研究同一个物体是更靠谱的，因为这种方法不仅会用到光，还会用到中微子乃至引力波。
Because neutrinos basically treat matter like it's nothing, measurements of them coming from things like blazars and black holes could reveal more about how those objects work.
由于中微子一般都会无视各种物质，所以对从耀变体或者黑洞出来的中微子进行测量可能会探究到中微子的运行机制。
We could learn things like the actual physics behind these beams of cosmic rays, even in environments where other research methods won't cut it.
我们了解到宇宙射线背后的物理学原理，即便是在其他研究手段一无所获的环境里，我们也会有收获。
So as we keep making discoveries like this, we'll be able to probe deeper into mysterious areas of physics than ever before.
所以在我们不断有类似的新发现后，我们就能进一步探索以前物理学未曾接触到过的神秘地区。
And we at SciShow Space are eagerly waiting for what's to come.
《太空科学秀》会一直关注接下来的新发现。
And thanks for watching this episode of SciShow Space News!
感谢收看本期的《太空科学秀》！
We could not bring you new information from around the universe every week without the support of our Patreon patrons, so special thanks to all of you who support this channel on Patreon.
如果没有忠实粉丝的支持，我们就无法每周为大家呈现有关宇宙的新消息，所以要特背感谢我们的支持者。
Thank you!
谢谢大家！
