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Last week a bunch of astronomers met in Liverpool for the European Week of Astronomy and Space Science.
上周，许多天文学家因《欧洲天文与空间科学周报》在利物浦相聚。
Quite a few gave some pretty cool presentations too, like one about how the Milky Way might be growing, which we talked about last week.
其中一些人也做了非常棒的展示，比如有一位天文学家就谈到银河系可能的演变方式，这个话题我们上周也讨论过。
But there's still a lot of cool things to talk about!
但依然有很多有趣的话题可以讨论！
It turns out that solar tornadoes are not actually tornadoes, at least according to one international team.
比如，太阳能龙卷风并不是龙卷风，至少有一个国际天文学家小组不是这样认为的。
A solar tornado is a super cool name for a hot plasma structure sticking off the Sun's surface.
这个名字听起来很酷，其实它是太阳表面一种温度极高的等离子体结构。
They can be up to around two million degrees Celsius, and they appear to have similar-looking shapes to the twisters we see on Earth.
它的温度可达近200万摄氏度，形态跟我们在地球上看到的龙卷风类似。
Except, like most things on the Sun, each one is way bigger than our whole planet.
只不过，其规模要比整个星球都大得多。
And they're created because of the Sun's really complex magnetic field rather than wind and different-temperature air mixing together.
其之所以会形成是因为太阳的磁场相当之复杂，而不像地球一样只是风和有温差的气体的简单混合。
They also appear to be anchored below the Sun's surface, so they don't move around much.
这种龙卷风也只发生在太阳表面一下，不会到处移动。
Solar tornadoes were first observed about a century ago, but thanks to Sun-studying spacecraft
人们第一次观测到这种现象是在大约一个世纪以前，不过，由于现在我们有了研究太阳的宇宙飞船，
like NASA's Solar Dynamics Observatory, astronomers are now able to study them in more detail.
比如美国宇航局的太阳动力学天文台，所以天文学家现在可以探究到这种现象的更多细节。
Based on 2D images, it looks like some of the Sun's plasma is rotating up and away from the surface to form 3D tornado shapes.
从二维图像可以看到，太阳的一些等离子体似乎在向上旋转并远离太阳表面，形成了三位的龙卷风形状。
But now, evidence suggests those plasma funnels aren't actually tornado-shaped at all. They only look like they are.
不过，如今已有证据表明，这些等离子体形成的“漏斗”并不是真的具备龙卷风的形状，只是看起来像罢了。
In their presentation, the researchers described how they created new 3D ‘images' of some select solar tornadoes that occurred between 2014 and 2016.
在展示中，这些天文学家描述了他们创建新三位图像的方法，针对的对象就是他们从2014-2016年间挑选的几次太阳上的龙卷风现象。
They did this by adding in newer measurements, which allowed them to calculate not only the plasma's velocity, but its temperature and density, too.
过程中，他们还加入了一些新的测量方法，这样，他们能计算的就不仅是等离子体的速度，还有其温度和密度。
So they got a better idea of what the magnetic field was up to and the structures it was forming.
所以他们对磁场的作用以及磁场的结构有了更深的了解。
It turns out that the Sun's magnetic field lines aren't twisting the plasma up into tall tornado shapes at all.
结果显示，太阳的磁场线并没有使等离子体向上涡旋成龙卷风的形状。
Instead, the plasma's moving mostly horizontally with respect to the Sun's surface.
相反，等离子体几乎是呈水平方向地在太阳表面移动。
A solar tornado only looks like a funnel because of perspective.
只是因为视角的原因，才看起来像漏斗。
And now that we have some 3-dimensional data, things are starting to look different.
现在，我们有了三维数据，图像看起来就不同了。
The team did find some helical motion by tracking certain knots of plasma,
该研究组确实发现等离子体的部分地方呈现螺旋形的移动状态，
but it was nowhere near as fast as the measured horizontal velocity, which was up to 65 kilometers per second!
但比我们测量的65km/s的水平速度差远了。
So it might be time to rename solar tornadoes. We'll just have to wait for peer-review to be sure.
所以，要给它重新命名，还需要些时间，我们要等相关的同行评审出来后才能确认新名字。
Meanwhile outside Liverpool, last week's Nature Astronomy reported astronomers
那么，也说点儿利物浦之外的事儿，上周根据《自然-天文学》的文章，
have captured radio images of a galaxy's core using a telescope bigger than the Earth.
一些天文学家通过望远镜捕捉到了某星系内核的射电图像，比地球还要大。
Most, if not all, large galaxies have supermassive black holes in their centers.
大多数星系甚至说所有星系的中心都有特大质量的黑洞。
They're millions, if not billions, of times more massive than our Sun. A select few of those black holes are what astronomers call active.
它们的质量是地球的数百万倍乃至数十亿倍，根据天文学家的说法，其中有一些黑洞是活跃的。
They're gobbling up so much matter that the galactic nucleus radiates a bunch of light.
黑洞吞噬了太多的物质，以至于星系核会辐射出一束光。
The magnetic fields of these objects can also direct some of the infalling matter out into jets, which travel at half the speed of light or more.
这些物体的磁场也可以将落入黑洞的一些物质引导到喷流中，喷流的速度至少是光速的一半。
These jets can be so big they expand beyond the entire galaxy! But exactly how these jets come to be has been a mystery,
喷流覆盖面很大，甚至可以超越整个星系！但这些喷流的形成原因一直都是个谜，
because astronomers haven't been able to get really high-resolution data from close enough to their sources.
因为天文学家还没能得到关于它们的高清数据。
While there are computer models, we don't have the observational data to confirm if they're accurate.
虽然现在有一些电脑模型，但我们没有观测资料，所以无法确认这些模型是否是准确的。
To try and track some down, an international team of astronomers trained their sights on the galaxy NGC 1275, located about 230 million light-years away.
为了找到数据，某国际天文学家小组将目光放到了NGC 1275星系上，这个星系距离我们大概有2.3亿光年。
The jets coming from its black hole known as 3C84 are actually super new on an astronomical scale.
从这个星系的黑洞里射出的喷流，也就是3C84，实际上在天文学里还是相当新的概念。
They're only ten years old. But to get the ultra-clear resolution needed to study them,
我们十年前才发现它，但是要想得到研究所需的超清图像，
these astronomers needed a telescope bigger than the entire planet, which, if you haven't noticed, is not something they sell on Amazon.
天文学家就需要一种比地球还大的望远镜，大家可能听说过亚马逊上卖的那种超大望远镜，但并不是那种。
Still, it's totally possible thanks to a method called interferometry, or using an array of telescopes to observe the same object at the same time.
这种望远镜之所以有可能实现，全靠干扰量度法，或者用一排望远镜来同时观测同一个物体。
If you do that, the resolution becomes equal to the average separation between the telescopes, rather than just the size of a single dish.
通过使用这个方法，分辨率就能取各个望远镜的平均值，否则分辨率就会很低。
We've actually been doing this on a smaller scale for decades, like at the Very Large Array in New Mexico, and ALMA in Chile.
实际上，过去几十年来，我们一直都在小范围内使用这个方法，比如在新墨西哥州的甚大天线阵和智利天文台。
To study 3C84, the team used the RadioAstron interferometer, which is made up of telescopes positioned all over the world, plus one in orbit.
为了研究3C84，该小组使用了射电望远镜干扰度量法，汇集了分布于全球各地的望远镜，加上一个在轨道运行的望远镜。
All together, they have an angular resolution equal to 350,000 kilometers, which is nearly the distance from the Earth to the Moon!
这样的话，他们加起来的角坐标分辨率就达到了35万千米，近乎地球到月球的距离！
So, technically, it's bigger than Earth.
所以从技术角度来讲，比地球还要大。
With this network, they were able to resolve 3C84's jet structure ten times closer to the black hole than previous observations.
有了这个望远镜的网络，他们就能在距离黑洞近10倍的地方解析3C84的喷流结构了。
Admittedly, that distance is still 12 light-days away from the source, but hey. Baby steps.
不可否认的是，这个距离观察源依然有12光年的距离，但已经很好了，不是么？毕竟我们还在起步阶段啊。
So far, we've learned that the jets at that distance were a lot wider than expected.
目前为止，我们了解到的情况是，喷气射流比我们想象的跨度更宽。
They are wider than any previously measured, in fact.
实际上，也比之前测量的结果更宽。
They're so wide that it could mean that they start in a region around the black hole
这个宽度太大了，这样的宽度表明，喷流是在黑洞附近的吸积盘中形成的，
called its accretion disk which shouldn't happen based on our current models.
但我们现有的模型得不出这一点。
Instead, these models assume jets start at a place called the black hole's ergosphere.
相反，根据现有的模型，喷流是在黑洞的能层形成的。
It's an area right outside a rotating black hole's event horizon, where space is literally dragged around.
能层恰好在旋转着的黑洞视界的外面，这里的空间已经发生扭曲。
The new data doesn't rule that hypothesis out, but it does sit at the edge of what's allowed, so it's worth more investigation.
这项新数据并不能否决假设的真实性，但数据确实有些不符合常理的迹象，所以值得我们进行更多的研究。
Of course, there's also a chance that, because the jet is so young, we might not even be seeing its final structure.
当然了，还有一种可能性就是，由于喷流形成时间较短，所以我们可能还没能看到其最终结构。
So, further study could also help astronomers better understand how these active galactic nuclei evolve.
所以，进一步的研究或许也可以帮助天文学家更好地理解这些活跃的星系核是如何演变而来的。
Thanks to technology like interferometers, we're getting better and better at studying the distant reaches of our galaxy.
我们要感谢望远镜干扰度量法，因为它，我们在研究星系遥远地方取得了越来越多的进展。
And there's no telling what'll come next. Thanks for watching this episode of SciShow Space news!
或许未来还有更多意想不到的发现，感谢收看本期的《太空科学秀》！
There's a lot we don't know about the universe or even our solar system,
我们对宇宙甚至太阳系还知之甚少，
so if you'd like to keep learning about it with us, go to youtube.com/scishowspace and subscribe.
所以如果大家想继续同我们一起了解宇宙的话，可以订阅youtube.com/scishowspace。
