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Even though it’s 4,500 years old, the Great Pyramid of Giza still has some secrets.
即便已经有4500年的历史了，吉萨大金字塔仍然有一些秘密尚未解开。
Recently we discovered a new one, and we did it using subatomic particles from space.
最近我们又揭开了一个关于吉萨大金字塔的秘密，还用到了太空中的亚原子粒子。
The particles in question are called Muons,
这种粒子叫作μ子（Muons），
and they’re like relatives of electrons if electrons really let themselves go;
而且它们也可以说是电子的亲戚，如果电子真的能够自己动起来的话；
a muon has about 200 times more mass than an electron.
μ子的质量大约是电子的200倍。
They’re generated when cosmic rays --usually protons from stars-- collide with particles in our upper atmosphere.
宇宙射线 - 通常是恒星的质子发出的射线 - 与我们上层大气中的粒子碰撞时，就会产生这种粒子。
The newly formed muons rain down and about 10,000 hit every square meter of the earth’s surface every minute.
之后它们就会像雨点般落下，每分钟落入地球表面每平方米的μ子有将近1万个。
You may have noticed, or not noticed rather, that you’re not getting pummeled to death by a particle shower all the time.
您可能已经注意到了，但还是宁愿没有注意到吧，您并不会被这些纷纷落下的μ子砸死。
That’s because muons pass right through stuff with ease.
这是因为μ子很容易穿过物体。
It’s what tipped off 1930s quantum physicists that what they were looking at wasn’t some type of electron,
就是这样，20世纪30年代量子物理学家才发现他们观察到的并不是某种电子，
but it’s own distinct elementary particle.
而是有着独特结构的基本粒子。
Even though they can travel through the densest materials, that doesn’t mean they’re unaffected by them.
即便最密集的材料它们也能穿透，这并不意味着μ子能够丝毫不受这些材料的影响。
Muons have a negative charge, meaning when they come near electrons, their like charge repels the muon, deflecting it and slowing it down.
μ子带负电，这就意味着它们接近电子时，带有相同电荷性质的的电子就会排斥μ子，从而改变其运动方向和运动速度。
Since muons decay into electrons and neutrinos after just 2 millionths of a second,
由于仅仅百万分之二秒的作用就能让μ子衰变成电子和中微子，
really dense materials can slow some muons down enough to stop them, but many will still make it through.
真正密实的物质是可以让某些μ子速度降下来甚至停止运动的，但还是有很多μ子能够穿透材料。
Scientists can use these properties to give them x-ray vision.
科学家可以利用这些特性对它们进行X光扫描。
Actually it’s better than x-ray vision,
事实上，这种粒子比X光扫描还要好，
because x-rays can be blocked by dense materials while muons can come clean out the other side.
因为X光会被密实的材料阻挡，而μ子可以穿透到另一侧。
Really, Superman should have had muon vision, instead of dumb old x-ray vision.
说真的，超人应该给自己装上μ子透视眼，而不是愚蠢而老旧的X光透视眼。
That’s right, I’m suggesting they nerfed Superman.
没错，我就是想说他们把超人变弱了。
Anyway, scientists can use muons to see through buildings using a technique called Muon Tomography.
不过，话说回来，科学家已经能用μ子看到建筑物内部的情况了，这种技术就叫“μ子断层扫描技术”。
Muons travel more slowly through materials with higher atomic numbers,
μ子穿透物质的速度较慢，但穿透率较高，
so by measuring how muons from cosmic rays are deflected when they pass though a big stone building,
所以，通过检测宇宙射线中的μ子在穿过石砌建筑时的衰减率，
scientists can map out what they must have passed through.
科学家们就能推算出射线穿透的建筑材质。
And there’s no bigger or stonier building than the Great Pyramid of Giza.
而世界上又没有比吉萨大金字塔更大或更宏伟的建筑。
Well technically there is, but you get the idea.
嗯，严格来说还是有的，但你明白我的意思就好了。
Plus since the pyramid is so dang old, it’d be best to explore it in a way that doesn’t harm it.
此外，由于金字塔实在是太古老了，所以我们最好用一种不伤害它的方式来对它进行探索。
For that, muon tomography is a perfect fit.
这样一来，μ子断层扫描技术就再合适不过了。
In December of 2015, researchers put a muon detector inside the pyramid in what’s known as the “Queen’s Chamber.”
2015年12月，研究人员将一台μ子探测器放入了金字塔中的“王后室”。
Sure enough their results showed a heretofore undiscovered void,
结果果然探测到了迄今为止尚未发现的密室，
and two separate teams using different kinds of muon detectors in different locations inside and outside the pyramid confirmed the findings.
两个团队分别在金字塔内外不同位置使用不同种类的μ子探测器进行探测，他们的结果证实了这一发现。
The void is the first new discovery of a major space inside the pyramid since the 19th century,
这一密室还是自19世纪以来首次在金字塔内主体内部发现的密室，
although scientists did try and use muon detectors inside it back in the 1960s
尽管20世纪60年代就有科学家尝试用μ子探测器研究这一金字塔了，
but the technology was not as sensitive then as it is now.
但当时的技术还没有现在这样灵敏。
Muon detectors have come a long way, especially since September 11th, 2001,
μ子探测器已经走过了漫长的道路，特别是自2001年9月11日以来，
when fears of a terrorist attack spurred research into technology that could detect hidden nuclear weapons.
对恐怖袭击事件的恐惧促使人们开始研究能够发现隐藏核武器的技术。
Today muon detectors can scan a 40 foot shipping container in 45 seconds, revealing any nuclear materials inside.
如今，μ子探测器可以在45秒内扫描一个40英尺的集装箱，发现箱内任何一种核材料。
And there’s no use trying to hide a bomb by shielding it with lead,
在炸弹外面涂铅也没有用，
because the muons can go right through that too
因为μ子也可以直接穿透铅涂层，
and the scanners will just show that there’s a bomb AND some lead.
扫描仪也会直接显示有炸弹和铅。
As much as I’m glad that muon detectors are helping to keep us safe,
μ子探测器能够帮助保护我们的安全我很高兴，
I just love that some mad genius thought to use them in the pyramids.
看到一些疯狂的天才用他们来扫描金字塔的想法更让我高兴。
Where else are you going to find such an awesome convergence of astronomy, particle physics, and egyptology?
还有什么比天文学，粒子物理学和埃及学的融合更让人敬畏的呢？
Besides Stargate, obviously.
当然了，除了星际之门之外。
Want more Seeker?
想收看节目更多内容？
You can find us on TV under the name SEEKER NOW!
大家现在也可以直接在电视上看我们的节目了，节目名称就叫SEEKER。
Watch SEEKER NOW on TBD Wednesdays 9pm/8c!
TBD每周三东部时间晚上9点，中部时间晚上8点与您不见不散！
To find TBD in your area and stream it anywhere, download the TBD What’s Next app or visit TBD.COM.
查找周边的TBD或者想随时随地下载视频，请下载TBD应用程序或访问TBD.COM。
Thanks for watching SEEKER！
感谢您收看我们的节目！
We're always making new videos so you should go ahead and subscribe for more.
我们一直在制作新视频，想看更多内容就赶紧订阅吧。
Muon detectors have also been used at Fukushima to map out where nuclear materials inside the damaged reactors are.
福岛也用了μ子探测器来确定受损反应堆内核材料的位置。
That disaster is still ongoing, and we’ve just found a new source of radiation.
那场灾难至今仍在继续，我们刚刚找到了新的辐射源。
Trace has more on that here.
Trace在这期视频里就讲到了这一问题。
That’s all for now, thanks for watching Seeker!
今天的节目就到这里，感谢大家的收看！
