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Astronomers use x-rays to study stuff in space all the time.
一直以来，天文学家是通过X射线来研究太空中的物质的。
They're a fairly standard part of the toolkit.
X射线是天文学家的一项常规工具。
But this week, in a paper published in Nature Astronomy, an international team used a new strategy in order to observe a very distant, very young galaxy undergoing rapid star formation.
不过，本周，在《自然天文学》上发表的一篇论文中，一组国际团队通过一项新策略来观测了一个遥远的年轻星系，这个星系正在经历快速的恒星形成过程。
Basically, they used a galaxy cluster to look at the x-rays emitted by a galaxy behind it.
天文学家基本上是通过星系团来观测其背部星系放射出的X射线的。
And they did so in order to look into the very, very distant cosmic past.
他们这样做是为了了解宇宙遥远的过去。
Massive bodies like galaxies have gravity, and gravity can bend light.
像星系这样质量庞大的物体是有引力的，而引力会让光发生弯曲。
The bigger the body, the bigger the light bending, and as the light bends, its source appears magnified to us.
物体的体型越大，光弯曲的程度越大。光越弯曲，其光源在我们看来就越大。
It's like the lens in a telescope, except instead of being glass in a tube, it's something like a black hole in space.
这就好像望远镜中的镜头一样，只不过，与管道中玻璃相对应的是太空中的黑洞。
Also like a telescope, it helps us see things farther away than we normally could.
还有一点跟望远镜相似——它可以帮助我们看到正常情况下看不到的更远的物体。
This process is called gravitational lensing, and it works with all wavelengths of light.
这个过程叫做引力透镜，适用于各种波长的光。
Until now, however, lensing studies have mostly been done using lower-energy wavelengths, like infrared and microwave.
不过，目前为止，关于引力透镜的研究都是用低能波长做的，比如红外线和微波。
But really energetic phenomena, like star and galaxy formation, emit really energetic light, like x-rays.
但高能现象，如恒星形成和星系形成等现象，都会释放出高能的波长，比如X射线。
Which was just the ticket for observing this sprightly young galaxy.
这是我们观测年轻星系的一个切入点。
The light we can see from this galaxy is about 9.4 billion years old, so these observations represent a galaxy pretty early in the universe's life.
我们能从该星系中观测到的光波大概有94亿年的历史，
The newly-formed stars there were mostly low mass and low metallicity, meaning there were very few elements present that are heavier than helium.
新形成的恒星基本上质量都不大，引力较小，也就是说——比氦要重的元素要少一些。
But the fact that this galaxy is visible in x-ray light means that there's got to be x-ray sources there, and that's not these low-mass stars.
不过，实际上，该星系在X射线中是可见的，也就是说：那里一定有X射线的光源，但光源并不是这些低质量的恒星。
You gotta get real big and real energetic before you emit x-rays like that.
在释放出类似那样的X射线之前，应该会获得很大、能量很高的波才对。
When galaxies are young and forming lots of stars, some of those stars will form high mass x-ray binaries, or HMXBs, two big stars orbiting each other that emit a bunch of x-ray light.
在星系刚形成没多久，还在形成恒星的时候，其中一些恒星会形成高质量的X射线双星（HMXB）——2颗巨大的恒星，彼此环绕，会释放出一束X射线。
Unlike their low-mass siblings, these star pairs are huge and short-lived.
与低质量双星不同的是——这些恒星对儿体型庞大，生命周期很短。
Usually, one ends up dying, collapsing into a neutron star or maybe even a black hole, and then starts siphoning off its partner's atmosphere.
通常情况下，其中一个最后会消亡，会坍缩成中子星或者甚至是黑洞，然后开始吸食其伙伴恒星的大气层。
All this produces huge x-ray jets and shockwaves that can affect the whole galaxy, and even stuff outside of the galaxy, in ways we don't yet fully understand.
这整个过程都会产生大量X射线和冲击波，会影响整个星系甚至是星系外的物质，影响的方式目前我们并没有完全了解。
For instance, we don't know for sure how related star formation is to the formation of HMXBs.
比如，我们无法确定恒星形成跟HMXB形成之间的关系。
Maybe the shockwaves help trigger star formation.
或许，冲击波能助力触发恒星的形成。
HMXBs also may help us answer another big question in cosmology.
HMXB或许也能帮助我们解答宇宙中的另一个重要问题。
See, the intergalactic medium, that is, the gas between galaxies, has an electric charge, and we do not know why.
星系际介质，也就是星系间的气体是有电荷的，但我们不知道为什么。
It's basically a hot, charged plasma now, but observations of very distant and therefore very old targets suggest that it used to be totally neutral.
星系际介质基本上是温度很高的带电等离子体，但科学家对遥远的古老目标进行了观测后认为，星系际介质以前是不带电的。
So where did the charge come from? Well, those x-ray jets would definitely help!
那么，电荷是从何而来呢？X射线流起到了作用哦！
X-rays are a form of ionizing radiation, meaning they can totally charge gas.
X射线是电离了的辐射形式，也就是说X射线可以让气体带电。
That means enough galaxies with enough HMXBs could do the trick.
这就意味着——只要足够数量的星系里有足够数量的HMXB，星系际介质就能带上电荷，
Or, at least could be part of the trick.
或者出现类似的情况。
But either way, more studies of HMXBs will be a fascinating window into the early universe and the formation of the first galaxies.
不过，无论是哪种方式，如果能对HMXB做更多的研究，我们就能透过它来了解初期的宇宙以及早期星系的组成情况。
Much closer to home, after two years of delays, NASA got its ICON mission off the ground last Thursday.
说说离我们近的事儿——在拖了2年的时间后，NASA于上周四启动了ICON任务。
ICON is gonna orbit the Earth to study the upper-most, charged part of our atmosphere, called the ionosphere.
ICON将环绕地球飞行，研究地球大气层中最上方的带电部分——电离层。
It's where low-earth orbit is, so most of our satellites, including the ISS, live there.
所有近地轨道都在这里，所以，我们的大多数卫星，包括国际空间站也在这里。
When solar winds interact with the ionosphere, you can get beautiful auroras, and you can also get, like, satellite-damage.
每当太阳风跟电离层相互作用的时候，就会出现美丽的极光，但同时也会对卫星造成损害。
A bad enough solar storm could knock out GPS communications and be super dangerous to astronauts, so NASA is pretty motivated to figure out how to protect against that.
影响恶劣的太阳风暴会切断所有GPS通讯，对宇航员极为危险。因此，NASA有足够的理由去了解清楚如何防护人类不受太阳风暴的影响。
Until recently, we thought that the ionosphere was only affected by solar winds,
最近，我们想到——电离层只受到了太阳风的影响，
but it turns out that storms on Earth can affect it too.
但最后却发现——地球上发生的风暴也会影响电离层。
Extreme storms like hurricanes can produce turbulence that can churn up the atmosphere all the way to the ionosphere, creating really dense patches of plasma that we definitely don't want our satellites to go through.
飓风等极端风暴会产生扰乱作用，影响大气层甚至其中的电离层，产生大量密度很高的等离子体，对卫星十分危险。
But even less dramatic weather, like sustained winds, can produce turbulence in the ionosphere.
但即便不是极端天气，哪怕一直刮风，也会对电离层造成扰乱作用。
So ICON is going to study the ionosphere to better understand the connection between the sun, the ground, and the sky.
所以，ICON任务将会研究电离层，从而更好地了解太阳、地面、天空几者之间的关系。
And ICON's coolness isn't limited to the satellite itself.
ICON的优秀不止限于它对卫星的帮助。
The rocket that carried it has a very neat little launch procedure.
承载ICON的火箭，其发射流程也相当简洁。
Called Pegasus XL, it gets launched from the air.
该火箭名为飞马座火箭，是从空中发射的。
It's carried a little under 12,000 meters into the air by a huge plane, then it is let go, so it free-falls for about five seconds. And then it launches!
火箭是用某大型飞机运送到不到1.2万米的空中，然后火箭与飞机脱离。火箭进行了大概5秒钟的自由落体，然后发射了！
The idea is that, at that altitude, there's less friction from the atmosphere, so the rocket doesn't need as much fuel.
其设计的初衷是：在这样的高度下，大气层里的墨仓更少，所有火箭不需要那么多燃料。
And you don't need a fancy launch pad for it, just a runway.
而且也不需要发射台作为跑道了。
Of course, you still need jet fuel in the plane that gets it up there, so there's a tradeoff, but it's a launch process that the Pegasus rockets have used since the early 90s.
不过，飞机里还是需要燃料才能把火箭运送到空中的，所以这个方案是做了折中的。但这个发射过程是飞马座火箭自90年代初期就在使用的。
And it looks cool and it gets the science done, so win-win.
不仅看起来很酷，而且用到了科学原理，可谓双赢。
Thanks for watching SciShow Space, which is a Complexly production.
感谢收看本期的《太空科学秀》，本期节目由Complexly赞助播出。
And it is an exciting week here at Complexly, because we're trying something totally new.
本周对Complexly来说是非凡的一周，因为我们尝试的是全新的东西。
Actually, three somethings. It's Complexly Pilot season!
其实是有三样东西想介绍给大家。现在是Complexly Pilot季哦！
We're launching three brand new shows, each on their own channel.
我们推出了3款全新的节目，每款都在各自的频道上。
Each show will run for 3 episodes for 3 weeks, and then we will decide if we want any of those shows to continue on.
每个节目都会播放3周，有3集。然后我们会决定是否继续播出。
There's History Pop, which will dive into the intersection of history and pop culture, and will air on Tuesdays through the end of October.
它们是History Pop，该节目会深入介绍历史和流行文化，每周二播出，一直播到10月末。
Stories Retold, an all-ages series about fables and fairy tales, will go out on Wednesdays through the end of October.
Stories Retold，该节目会讲述各个年代的故事，每周三播出，一直播到10月末。
And Hashed Out, will help viewers navigate the media landscape from journalism to Twitter.
Hashed Out，该节目会帮助观众了解媒体，包括新闻业和推特等。
Posting Thursdays through, you guessed it, the end of October.
该节目是每周四播出，同样是播到10月末。
We love all of these ideas, but we don't have the bandwidth to make all of them happen at the same time, so we would love your feedback on what you think we should continue.
我们很喜欢这些点子，但我们没有足够的带宽来支持它们同时播出。所以我们希望得到大家的反馈，才能知道继续推进哪档节目。
Check them out and share your thoughts. Links are all in the description. Thanks!
请大家在观看后分享你们的想法。具体链接在描述中。谢谢大家！
