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Sometimes, astronomers can seem obsessed with finding water on other planets and moons, so you'd think it was super rare in the solar system.
有时候，天文学家会痴迷于在其他行星和卫星上寻找水源，这种举动给人的感觉就是：太阳系里的水源是非常稀少的。
But it's really not, and now we know of yet another place that might have water.
但其实并非如此，比如，我们找到了另一个可能有水源的地方。
It's just not one you might expect. In this month's edition of the Astronomical Journal, scientists reported hints of a water cloud deep within Jupiter's Great Red Spot.
这个地方，大家肯定意想不到。在这个月出版的《天文学期刊》中，科学家称他们发现有迹象表明木星表面大红斑下的深层可能存在水源。
It's not a sign astrobiologists should start looking for life there or anything, but it could help solve the mystery of how the largest planet in our solar system actually formed.
这个现象的发现并不是要天体生物学家开始去那里寻找生命的存在，但确实可以帮助我们解决一个谜题：木星这个太阳系里最大的行星是如何形成的。
Like the other gas giants, Jupiter is mostly made of hydrogen and helium.
跟其他气体星球一样，木星基本上也是由氢和氦组成的。
But astronomers have spent over a century trying to pin down what other compounds it's made of, and how abundant they are.
但科学家耗时一个多世纪才确定了这两种元素之外的组成成分及其含量。
Among other things, that could help us understand how and where the planet formed.
这个发现有助于我们理解木星的组成方式和形成地点。
For example, knowing how much water, or how much oxygen, Jupiter has could help answer the question of how far away from the Sun it had to have started.
比如，在知道了木星上有多少水和多少氧元素后，就能帮助我们解答这个问题：要让木星形成，那它距离太阳应该有多远才可以。
So far, computer models have been able to help a bit with these questions.
目前为止，计算机模型对于解答这些问题的帮助不是很大。
They suggest Jupiter has three different cloud layers:
计算机模型表明，木星有3个不同的云层：
The uppermost has a lot of ammonia, and below that it's ammonia and sulfur.
最上层有很多氨，其下面是氨和硫。
The bottom layer, though, is suspected to have water, both in solid and liquid form.
据我们的猜测，底层可能有水，固态液态都有可能。
But physical evidence of that water has been a bit elusive over the decades.
但过去几十年来，我们一直没有找到水源存在的切实证据。
And that's where this new study helped. This team analyzed data of the Great Red Spot, a centuries-old storm larger than Earth.
而这正是这个新研究可以帮助我们的地方。该小组分析了红斑的数据。这个红斑是比地球体积还要大的风暴，年龄有几百年。
Specifically, they used infrared data from a few telescopes and the Cassini spacecraft, which allowed them to penetrate Jupiter's opaque upper layers and get a look beneath the planet's surface.
研究人员用到了望远镜和卡西尼号宇宙飞船发回的红外数据。有了这些数据，研究人员就能透过木星并不透明的上层云层来一窥木星的表面以下。
They weren't directly looking for water, though.
不过，他们并非直接寻找水源。
Instead, they were mostly measuring the amount of a type of methane gas.
相反，他们基本上都在测量一种沼气的含量。
The abundance of this gas is roughly uniform in Jupiter's atmosphere, so if the group saw that abundance changing at all, it was likely that something, like a cloud layer, was blocking their signal.
木星大气层中这种气体的含量基本上是一致的，所以如果该小组能观测到这种气体含量的变化，就很有可能是什么东西阻挡了他们的信号，比如云层。
And that's exactly what they found! By studying the light traveling through Jupiter's clouds, the team could determine exactly how far down those different layers were.
而他们的发现结果果真如此！通过研究穿过木星云层的光线，该小组可以准确得知这些云层的方位。
Then, based on the pressures and temperatures at those depths, they could figure out what kinds of compounds could exist there.
然后根据这个距离的压强和温度，就能得出那里有什么样的化合物。
In the end, they did find three cloud layers, just as earlier models predicted.
最后，他们确实发现了3个云层，与先前的预测一模一样。
The deepest was 160 kilometers down, where the atmospheric pressure is around five times that of Earth's at sea level, and the temperature is just above the corresponding freezing point of water.
最深的在160公里下，那里的大气层压强是地球海平面的近5倍，那里的温度只比凝固点高一些。
That pressure and temperature suggests the presence of water down in those clouds, but right now, it definitely doesn't prove it.
这样的压强和温度表明云层中有水的存在，但目前我们还是无法确切证实这一点。
We'll need more research to actually be sure.
需要更多的研究才能确定。
Luckily for us, we currently have someone, or someTHING, on the case.
幸运的是，我们在这个研究里有了帮手。
Right now, the Juno spacecraft is investigating water on, or in, Jupiter.
目前，朱诺飞行器正在研究木星表面及内部的水源。
And it can look deeper than any of our other tech, up to where the pressures are 100 times that of Earth's atmosphere.
朱诺的探测深度比其他技术能实现的都要远，可以触及地球大气层压强100倍的地方。
So the team is waiting for our local planetary probe to back up their work.
所以，该研究小组正等待朱诺来支持他们的工作。
If it does, then we'll be able to further investigate water on Jupiter and maybe learn more about its origins, too.
如果朱诺确实能起到帮助的作用，那我们就能进一步研究木星上的水源，或许还能了解更多有关木星起源的知识。
Finding water on Jupiter would stick it in the same category as a bunch of other objects in the solar system, but don't worry: Jupiter is still super special.
如果能在木星找到水源，那木星就跟太阳系里的其他一些物体有一样的标签了，但大家别担心：木星还是不一样的烟火。
In fact, according to research published in Nature this Wednesday, it might have a magnetic field completely unlike any other planet.
实际上，根据本周三《自然》期刊上发表的一则研究，木星的磁场可能跟太阳系的任何一个行星都完全不同。
For the last couple of years, our little friend Juno has been doing more than just looking for water: It's been mapping Jupiter's magnetic field.
过去数年来，我们的好伙伴朱诺所做的工作并不仅仅限于寻找水源：朱诺还在勾勒木星的磁场图谱。
Astronomers had already crafted a new, more accurate model for the field outside Jupiter, based on eight of the spacecraft's passes around the planet, things like how strong it is and where.
天文学家已经为木星磁场勾勒出了一个更为精确的新模型，根据就是朱诺环绕木星飞行8圈所获得的数据，比如磁场的强度和地理位置。
But instead of looking at its surface, this team looked beneath the planet's cloud tops, up to a depth of 15% of Jupiter's radius.
但该小组并未观测其表面，而是观测了木星的云层顶部之下，深度大概是木星半径的15%。
There, it's suspected that the hydrogen inside Jupiter becomes a metallic fluid, which allows it to conduct electricity and generate a magnetic field.
科学家怀疑，在那里，木星里的氢元素是以金属液态的形式存在的，所以既可以导电，也可以产生磁场。
But that analysis showed something super weird.
但这个分析结果却也凸显了十分怪异的信息。
The team found that Jupiter's magnetic field looks different across the northern and southern hemispheres.
该小组发现，木星的磁场在南北半球看起来完全不同。
In the north, it's not a dipole, like you see in diagrams of the Earth's magnetic field.
北半球的磁场并非偶极，这跟地球的磁场图解不同。
But in the south, it is — and it's much weaker.
而南极的磁场比北极更弱。
The group measured something called the magnetic flux, or how strong a magnetic field is as it passes through a certain area.
该小组测量了磁通量。磁通量是衡量磁场通过某区域时强度多大的指标。
And they found that most of the flux comes out of the planet in a small band in the north.
他们发现，大多数磁流都是以小带状的形式从北极出来的。
Then, some of it loops back around and reenters the planet in a region near Jupiter's equator, called the Great Blue Spot.
然后，部分磁流会回过弯去，并再次进入木星近赤道的区域，该区域是大蓝斑。
Based on this, the team proposes that the mechanism that powers Jupiter's magnetic field has to operate differently than what we're used to seeing elsewhere in the solar system.
基于此，该小组开始提出：木星磁场提供能量的机制一定跟太阳系里其他地方的机制不同。
It's not like on Earth, where a thick shell of some electrically conductive fluid rotates as a single body.
反正跟地球的机制是不同的，因为地球是一些导电流体形成的厚层作为一个整体旋转。
Instead, there could be different layers, like different densities of metallic hydrogen at different depths.
木星的机制可能是：有不同的层，就像不同深度有不同密度的金属氢一样。
Or the layers could be better or worse at conducting electrical charge.
有可能是各层导电的能力强弱不同。
Maybe some helium rain is up to something, or maybe it has to do with dissolved parts of the planet's rocky, icy core, which is predicted by some studies.
也有可能是氦元素形成的雨在搞事情，或者与木星由石头组成的冰核发生了溶解有关（这是一些研究的预测）。
This new paper brought up a bunch of cool new questions, and we just don't know what's going on yet.
这片最新论文提出了许多很棒的新问题，目前，我们还不清楚答案。
Like with the water mystery, we need Juno to collect more data.
就像木星是否有水的谜题一样，这个谜题我们也需要收集更多的数据才能知晓。
For the moment, though, it definitely looks like Jupiter's magnetic field isn't like anything we've seen before.
目前来看，木星的磁场肯定是跟我们见过的其他磁场不同就是了。
So even if the planet turns out to be full of water, Jupiter is still in a class all its own.
所以，即便我们发现木星里充满了水源，木星的独特性还是使它自成一派。
Thanks for watching this episode of SciShow Space News!
感谢收看本期的《太空科学秀》！
If you'd like to learn even more about the weirdness of Jupiter's Great Red Spot, like where it came from and how long it'll exist, you can watch our episode all about it.
如果您想了解更多有关木星红斑的知识（比如红斑来自哪里、可以存在多久），我们的集锦里都有答案哦。
