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Here's a riddle for you: What objects combine giant balls of neutrons, black holes, the search for aliens, and doomed stars?
猜个谜题吧：什么现象囊括了巨型中子球、黑洞、搜寻外星人、恒星呢？
Give up? The answer is the blitzar: the flash from a type of hypothetical, dying neutron star.
猜到了么？答案就是快速电波爆发，这是我们假想中，中子星在即将消亡时爆发出的电波。
If they exist, they could be the solution to a mystery astronomers have spent years trying to solve.
如果快速电波爆发确实存在，就可以解决许多天文学家多年来一直努力解开的谜题。
And as a bonus, they're pretty weird, too. To understand blitzars, it helps to know a bit about neutron stars in general.
好事多磨，快速电波爆发也相当地不走寻常路，有了对快速电波爆发的了解，我们就能进一步了解中子星。
These objects can form when large stars die in gigantic explosions called supernovas.
中子星是在巨型恒星发生大爆炸时产生的，也就是超新星的形成过程。
If what's left over after the supernova is massive enough, gravity will pull it all into a black hole.
超新星形成后残留的东西如果质量足够大，就会被拖进黑洞里。
But if there's a little less stuff left over, gravity will sort of force together the protons and electrons from the old star's core.
但如果残留的东西质量不是那么大，那么重力会将恒星内核里残留的质子和电子结合在一起。
This creates an extremely dense ball of neutrons around fifteen kilometers across a neutron star.
这就在中子星周遭15公里的地方产生了密度极高的中子球。
Neutron stars aren't quite dense enough to become black holes, but they're close. And they're pretty extreme places in their own rights.
虽然中子星的密度没有达到形成黑洞的标准，但相差也不大，而且中子星本身也是条件非常极端的地方。
Just a teaspoon of neutron star has as much mass as Mount Everest, and its surface gravity is almost a trillion times stronger than Earth's.
埃佛勒斯峰只称得上是中子星的冰山一角，其表面的重力几乎是地球的万亿倍。
But for this story, the most important thing about neutron stars is that they spin very quickly, sometimes as fast as a few hundred times a second.
但这不是重点，重点是中子星的转速极快，有时候可达每秒几百次。
They also have super-strong magnetic fields, which can push around any gas that might be near the star.
此外，中子星磁场也极强，其附近的任何气体都逃不过它的手掌心。
As that gas moves, it emits radio waves. This actually caused a bit of a kerfuffle back in the 1960s.
气体流动过程中会释放无线电波，而这一点曾在上世纪60年引起了轩然小波。
Those radio waves can be so rapid and orderly that, when scientists first found signals from a neutron star,
这些电磁波不仅传播速度快而且十分有序，
some people thought they had to be messages from aliens. The signals were even named LGM-1 short for Little Green Men.
所以人们一开始发现中子星信号的时候，还以为是外星人传来的信息，大家甚至将该信号命名为“LGM-1”，意思是“小绿人”。
Of course, LGM was renamed after we figured out what it was, and neutron stars are at least a little less mysterious now.
当然了，在我们发现这并不是外星人传来的信号后就重新改了名字，所以，现在，至少中子星没那么神秘了。
Don't get me wrong, though they're still really weird. And in some situations, neutron stars can be extra strange.
不过，别误解我的意思哦，中子星在我们看来依然是难以捉摸的，有时候还可以说中子星是极度怪异的。
In fact, there's one hypothetical scenario where these stars are so dense that they should've been black holes from the beginning.
实际上，有一种假设的场景是：中子星密度达到，所以他们肯定是由黑洞变来的。
They're called supramassive rotating neutron stars, and they're the culprit behind blitzars.
这时候的中子星质量极大、转速极高，是快速电波爆发产生的根本原因。
The reason these stars wouldn't have become black holes is because their rotation would have spread out their mass just enough to avoid it.
而这样的中子星之所以没有变成黑洞，是因为他们的转速使自身的质量得以铺张开来，避免了成为黑洞的可能。
See, spinning objects tend to bulge out because of inertia, so a spinning object is a little bigger and a little less dense than a stationary one.
所以说，旋转中的物体由于惯性的原因，体积会变得更大，密度更小，这是与静止物体相对而言的。
That difference could be just big enough that it stops those supramassive neutron stars from collapsing.
这种差距是非常大的，会让这种中子星避免坍缩。
But that couldn't last forever. Like other neutron stars, these would have powerful magnetic fields.
但并不能永远避免坍缩，跟其他中子星一样，这种中子星的磁场也非常强大。
And over the years, those fields would carry enough energy away from the star and ultimately make it contract.
经年累月后，磁场会带走中子星的许多能量，最终导致中子星发生坍缩。
After anywhere between a few thousand and a million years, it would actually contract so far that it couldn't hold off gravity any longer.
在几百万年甚至几千年后的某一天，中子星就会收缩到无法再抵抗重力的作用。
The star would suddenly collapse into a black hole, releasing a powerful burst of radio waves as the magnetic fields get broken.
最终突然坍缩成黑洞，并随着磁场的瓦解而释放出大量的无线电波。
That powerful burst is a blitzar. Now, we don't have any concrete evidence that blitzars actually exist although there's no reason they shouldn't.
这种无线电波就是快速电波爆发，现在，我们还没有切实的证据可以表明快速电波爆发确实存在，虽然理论上而言，他们是存在的。
But if they do, the fast radio bursts they create would look a lot like a phenomenon scientists have been trying to figure out, called, well, Fast Radio Bursts.
但如果这种无线电波确实存在，那么他们所产生的快速射电暴就与科学家一直试图了解的一种现象非常相似了，那就是快速射电暴。
Over the last few years, scientists have found more and more of these signals, called FRBs for short.
过去几年来，科学家发现了越来越多的快速射电暴(FRB)。
They're exactly what they sound like: huge, quick bursts of radio waves.
顾名思义，快速射电暴就是短时间内迸发出的无线电波。
So far, astronomers aren't sure what causes them, and the ideas they do have are hard to test.
目前为止，天文学家还不确定引发快速射电暴的原因，所以，虽然有一些设想，但却无法证实。
FRBs don't usually repeat themselves, and we don't know where to look for the next one.
快速射电暴不会自我重复，所以我们不知道去哪里守株待兔。
All this uncertainty has maybe unsurprisingly led some people to speculate that FRBs must be from aliens.
这些不确定性已经，也可以说是毫不意外地，让一些人有这样的猜想：快速射电暴一定是外星人发出的。
But scientists also have a few good, non-alien ideas for explaining FRBs, including some that we've talked about before here on SciShow Space.
不过，科学家也想到了一些与外星人无关的引发快速射电暴的原因，其中一些，我们已经在之前的节目里讨论过了。
One other idea, suggested back in 2014 by a pair of European astronomers, is that blitzars would be the perfect solution for at least some of these signals.
其中一个想法是2014年两个欧洲天文学家提出的，即：快速电波爆发可能完美地诠释至少其中一些信号。
After all, blitzars are also huge radio bursts, and they also only happen once.
毕竟，快速电波爆发也是大型的射电暴，而且也只发生一次而已。
And if there were no gas around the supramassive neutron star before it collapsed, we probably wouldn't see any signals from it, either, like we did with LGM-1.
而且如果巨型中子星在坍缩之前周围没有气体的话，我们很可能也接收不到它发出来的信号，这就跟LGM-1形成了反差。
Of course, all of this means that blitzars would have to exist, which we don't know yet.
当然了，这些的前提是快速电波爆发是切实存在的，然而这一点我们还无法确定。
To find them, scientists could look for glowing clouds near the FRB's source, which might be some gas that didn't make it into the black hole.
为了证实快速电波爆发的存在，科学家可以寻找快速射电暴附近的发光云，发光云可能是没有形成黑洞的气体所形成的。
But these clouds would be dim and hard to find especially for distant FRBs.
但这种云颜色灰暗，难以寻找，尤其是很难找到快速射电暴。
Still, we don't know any real reason blitzars shouldn't be out there, though, so there's hope.
不过目前还没有理由断言快速电波爆发的存在，所以还是有希望的。
And if they are, it would mean that once again, neutron stars ruined our alien fun by being so darn cool.
而如果当真存在，那么也就意味着中子星再次以其冷艳style摧毁了我们幻想外星人存在的乐趣。
Thanks for watching this episode of SciShow Space!
感谢收看本期的《太空科学秀》！
If you'd like to keep exploring the weird, surprising, and awe-inspiring universe with us, you can go to youtube.com/scishowspace and subscribe.
如果您还想和我们一起继续探索令人吃惊、引人敬畏的奇怪宇宙，那就订阅youtube.com/scishowspace吧。
