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Even though it's 4,500 years old, the Great Pyramid of Giza still has some secrets.
尽管已经屹立于世长达4,500年之久，吉萨大金字塔仍然蕴含着诸多未解之谜。
Recently we discovered a new one, and we did it using subatomic particles from space.
最近我们利用了来自太空的亚原子粒子，发现了一个新的谜题。
The particles in question are called Muons, and they're like relatives of electrons if electrons really let themselves go.
这些粒子被称为μ子，如果电子真的可以自行释放，它们就像是电子的亲戚。
A muon has about 200 times more mass than an electron.
μ子的质量比电子高出大约200倍。
They're generated when cosmic rays --usually protons from stars-- collide with particles in our upper atmosphere.
当宇宙射线（通常是来自恒星的质子）与我们上层大气中的粒子发生碰撞时，它们就产生了。
The newly formed muons rain down and about 10,000 hit every square meter of the earth's surface every minute.
新形成的μ子下落，每分钟大约对每平方米地表产生10,000次撞击。
You may have noticed, or not noticed rather, that you're not getting pummeled to death by a particle shower all the time.
你可能已经注意到了，或者没有注意到，你并没有被粒子簇射杀致死。
That's because muons pass right through stuff with ease.
这是因为μ子很容易穿过物质。
It's what tipped off 1930s quantum physicists that what they were looking at wasn't some type of electron,
20世纪30年代的量子物理学家们说，那时他们所看到的不是电子，
but it's own distinct elementary particle.
而是其不同的基本粒子。
Even though they can travel through the densest materials, that doesn't mean they're unaffected by them.
即使它们可以穿过最致密的材料，但也并不意味着它们不会受到这些材料的影响。
Muons have a negative charge, meaning when they come near electrons, their like charge repels the muon, deflecting it and slowing it down.
μ子具有负电荷，这意味着当它们接近电子时，它们类似的电荷会产生排斥作用，使得他们发生偏转，减速。
Since muons decay into electrons and neutrinos after just 2 millionths of a second,
因为μ子衰变成电子和中微子时间长度为两百万分之一秒，
really dense materials can slow some muons down enough to stop them, but many will still make it through.
真正致密的材料可以使一些μ子减慢速度，无法通过，但许多μ子仍然可以成功通过。
Scientists can use these properties to give them x-ray vision.
科学家们可以利用这些特性实现X光透视。
Actually it's better than x-ray vision, because x-rays can be blocked by dense materials while muons can come clean out the other side.
事实上，它比X光透视更好，因为X射线可以被密集的材料阻挡，而μ子不会。
Really Superman should have had muon vision, instead of dumb old x-ray vision.
真的，超人应该有μ光透视，而不是破烂X光透视。
That's right, I'm suggesting they nerfed Superman.
没错，我是说他们耽误了超人。
Anyway, scientists can use muons to see through buildings using a technique called Muon Tomography.
无论如何，科学家们可以使用μ子，通过一种叫做μ子断层扫描的技术来看穿建筑物。
Muons travel more slowly through materials with higher atomic numbers,
μ子在通过高原子序数的材料时速度更慢，
so by measuring how muons from cosmic rays are deflected when they pass though a big stone building,
因此，通过测量来自宇宙射线的μ子在通过石制建筑时的偏转情况，
scientists can map out what they must have passed through.
科学家们可以绘制出它们的运动轨迹。
And there's no bigger or stonier building than the Great Pyramid of Giza.
没有比吉萨大金字塔更大更坚固的建筑了。
Well technically there is, but you get the idea.
严格来说还有，但你明白我的意思。
Plus since the pyramid is so dang old, it'd be best to explore it in a way that doesn't harm it.
另外，因为金字塔已是千年之身，最好用一种不伤害它的方式进行探索。
For that muon tomography is a perfect fit.
μ子断层扫描完全适合。
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，研究人员在金字塔中放置了μ子探测器，称为“Queen's Chamber”。
Sure enough their results showed a heretofore undiscovered void,
果然，他们的结果显示出金字塔内存在迄今为止尚未发现的空洞，
and two separate teams using different kinds of muon detectors in different locations inside and outside the pyramid confirmed the findings.
两支独立团队使用不同的μ子探测器在金字塔内外不同位置证实了这一发现。
The void is the first new discovery of a major space inside the pyramid since the 19th century,
空洞是自十九世纪以来金字塔内主体空间的第一新发现，
although scientists did try and use muon detectors inside it back in the 1960s but the technology was not as sensitive then as it is now.
虽然科学家们在20世纪60年代，曾尝试使用μ子探测器，但当时技术水平并不像现在那样敏锐。
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发展道路，尤其是2001年9月11日以来，
when fears of a terrorist attack spurred research into technology that could detect hidden nuclear weapons.
对于恐怖袭击的恐惧促使人们加强了探测隐秘核武器技术的研究。
Today muon detectors can scan a 40 foot shipping container in 45 seconds, revealing any nuclear materials inside.
今天，μ子探测器可以在45秒内扫描一个40英尺的集装箱，并可显示出任何核材料的存在。
And there's no use trying to hide a bomb by shielding it with lead,
如果藏匿炸弹，用铅屏蔽，无效，
because the muons can go right through that too and the scanners will just show that there's a bomb AND some lead.
因为μ子也可以通过铅皮，扫描仪只会显示那里存在炸弹和一些铅皮。
As much as I'm glad that muon detectors are helping to keep us safe,
我很高兴μ子探测器帮助我们保障了安全，
I just love that some mad genius thought to use them in the pyramids.
我也欣慰那些疯狂的天才想法在金字塔上的应用。
Where else are you going to find such an awesome convergence of astronomy, particle physics, and egyptology?
除此以外，你到哪里去找天文学、粒子物理学以及古埃及学惊人的融合呢？
Besides Stargate, obviously. Want more Seeker?
显然，除了星际之门。还想观看更多科学探秘节目？
Muon detectors have also been used at Fukushima to map out where nuclear materials inside the damaged reactors are.
μ子探测器在福岛也有应用，它们用来帮助绘制受损反应堆内部的核材料。
That disaster is still ongoing, and we've just found a new source of radiation.
那场灾难还在继续，我们刚刚发现了一个新的核辐射源。
Trace has more on that here.
特雷斯为您带来更多内容。
That's all for now, thanks for watching Seeker!
先到这里，感谢收看！
