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Saturn’s moon Enceladus has fascinated scientists for decades.
几十年来，土卫二一直是许多科学家关注的焦点。
I mean, it’s one of the shiniest objects in the solar system, thanks to its ice-covered surface.
毕竟它是太阳系里最闪耀的物体之一，这是因为它表面都是冰层覆盖。
And scientists love shiny objects, just like all the rest of us!
科学家跟我们一样，也喜欢闪闪的物体。
Geysers at its south pole launch water and organic molecules from its global subsurface ocean into Saturn’s beautiful ring system.
南极的间歇泉从其在全球范围内的次表层海洋喷射出水分子和有机分子，喷射到土卫二美丽的环系中。
Now, a paper in the journal Nature Astronomy claims that there are spots on the surface with an awful lot of heat coming from the ocean below.
现在，《自然天文学》期刊上发表的一篇论文指出，表面的一些点里有大量热量从地底的海洋中喷射而出。
And if Earth’s any guide, that’s a pretty good starter pack for life.
如果说地球是指南的话，那么这里就是试炼第一步的绝好开始。
In the paper, an international group of researchers looked at measurements that the Cassini probe’s RADAR instrument made back in 2011.
撰写这篇论文的一组国际研究人员查看了一些测量数据，这些数据是卡西尼号太空船的雷达设备于2011年捕获的。
Radar usually shines microwaves on something and learns about its surface features based on how the microwaves bounce back.
雷达通常会在某些事物上发射微波，然后根据微波弹回的方式来了解该事物的表面特征。
But Cassini’s RADAR instrument is designed so that if you turn the transmitter off, it can still detect the light given off by the surface itself.
但卡西尼号的雷达设备设计成了这种模式：即便关掉发射机，它依然可以检测到物体表面放射的光。
And that can tell you about its temperature -- like how seeing that metal is glowing red tells you it’s hot.
这样就可以判断物体表面的温度——就像通过金属烧红可以判断金属温度很高一样。
As it flew over Enceladus’s south pole, Cassini measured a stripey pattern of temperature changes near the pole right next to a bunch of fractures in the surface.
卡西尼号飞过土卫二南极的时候，会以条纹模式呈现南极附近的温度变化，测量地就在土卫二表面的一系列断裂处。
Scientists have thought for a while that Enceladus’s ice might be broken up into big sections that act like icy versions of Earth’s tectonic plates.
有那么一段时间，科学家一直认为土卫二的冰层可能被切分成了一些大块，这些大块就像地球地壳构造板块上的冰层部分一样。
And these stripey temperature measurements seem to confirm that idea.
而以条纹形式呈现的温度测量结果似乎与这份数据不谋而合。
Most of Enceladus’s heat comes from tidal effects, where Enceladus gets stretched and flexed by Saturn’s gravity as it orbits.
土卫二的大多数热量都来自潮汐作用，因为土卫二在环绕飞行的过程中会受到土星引力的拉伸作用。
Thin ice flexes and heats more than thick ice, and it also lets more underground heat through to the surface.
薄冰的拉伸程度和发热程度要大于厚冰，而且薄冰从地下释放的热量也大于厚冰。
So higher surface temperatures probably mean thinner ice.
所以地表温度越高，冰层就越薄。
And plates with different thicknesses would make patterns of warmer and cooler areas on the surface -- just like Cassini measured.
不同薄厚的地壳板块会在表面形成不同温度模式的区域——就像卡西尼号观测到的那样。
Icy plates would also make something like volcanoes and faults that we see at Earth’s plate boundaries -- again, just like the geysers and fractures Cassini saw a few years ago.
冰层板块还可以产生像火山和断层一样的东西，这种景象我们在地球板块的边缘处也可以看到——这些景象依然与几年前卡西尼号观测到的间歇泉和断裂处不谋而合。
So between the higher temperatures and active geysers, the ice near the south pole could be way thinner than we used to think.
所以在高温和活跃的间歇泉之间，南极附近的冰层可能比我们过去所认为的还要薄。
Based on the evidence they’d collected before this, astronomers estimated that the ice on Enceladus might be 30 or 40 km thick in some places, and maybe 5 km thick at the south pole.
根据他们此前收集到的数据，天文学家估测认为，土卫二的冰层可能有些地方是三四十公里厚，而南极可能有5公里厚。
But now, it seems like ice right near the pole might be as little as 2 km thick!
但现在，似乎南极附近的冰层只有2公里厚！
All this makes the south pole a prime target if we ever want to send something to check out the oceans under the ice.
这就让南极成了我们探测海底冰层的主要目标。
And we might actually do that, because heat bubbling up from the bottom of a huge, salty ocean of liquid water and organic molecules sounds a lot like the conditions where life first evolved here on Earth.
而且我们或许真的会这样做，因为热量从巨大的液态盐海里涌出，里面都是有机分子，这听起来很像地球上生命刚开始孕育的时候。
If there’s life anywhere else in our solar system, Enceladus is one of the best places to look for it.
如果太阳系里还有可能有生命存在的地方，那土卫二绝对是寻找生命的绝好地点。
Meanwhile, other researchers are looking into how our entire universe came to be in the first place.
同时，其他研究人员也在观测整个宇宙最开始形成的方式。
In a recent video over on the main SciShow channel, we talked about five big mysteries that poke holes in our understanding of the universe.
最近，科学秀频道发布了一则视频，其中我们探讨了5个巨大的谜题，这5个谜题如果能解开，我们对宇宙的了解将大进一步。
But if a recent paper in The Astrophysical Journal has anything to say about it, that number could drop down to four.
但《天文物理期刊》上最近发表的一篇论文却只提到了其中的4个谜题。
A few minutes after the Big Bang, the universe was filled with a hot plasma of particles that sometimes fused together to form the first few elements on the periodic table.
宇宙大爆炸数分钟后宇宙里都是高温等离子体，这些等离子体有时候会发生融合，形成元素周期表上的前几种元素。
So hydrogen fused into helium, and then helium combined into different types of lithium and beryllium.
按照这个思路，氢会融合为氦，而氦会融合形成不同的锂和铍。
And our current model of this process does a great job of predicting how much of each element was produced.
我们当前对于该过程的建模可以很好地预测每种元素产生的量。
Except lithium-7, a type of lithium with four neutrons.
除了锂7之外。锂7是带有4个重子的锂原子。
There was about a third as much lithium-7 in the early universe as the model predicts, and there’s no accepted explanation for why.
宇宙初期只有如今1/3的锂7，这跟模型的预测不谋而合。对此，至今还没有普遍认可的解释。
But the authors of this paper are proposing a pretty simple way around this frustrating problem.
但该文作者提出了一个相当简单的办法来解决这个疑惑。
Cosmologists generally assume that that plasma throughout the early universe acted like what’s called an ideal gas.
宇宙学家普遍认为，宇宙初期的等离子体就像理想气体一样。
Ideal gases are in equilibrium: They look pretty much the same everywhere.
而理想气体是平衡的，在哪里都一样。
And assuming the plasma stayed in equilibrium leads to those great predictions of the amounts of elements — besides for lithium-7.
假设等离子体可以保持平衡状态，这样我们就可以很好地预测元素的总量——除了锂7之外。
But by the time lithium was forming, that plasma was really quickly cooling down to where new elements couldn’t fuse together anymore.
而等锂形成的时候，等离子体很快就会降温到不再融合出新元素的程度。
And as the authors point out, there aren’t great reasons to assume this happened at the same time everywhere.
正如本文作者所指出的，但我们没有理由认为这种现象会在各处同时发生。
So the plasma might not have been in equilibrium as it cooled.
所以等离子体冷却之时可能并非出于平衡状态。
By changing that one assumption, the researchers were able to create a model that predicts the right amounts of every early element – including lithium!
改变了这个假设条件后，科学家就能建造出一个模型，该模型可以预测每种初期元素正确的含量——甚至包括锂！
If they’re right, it’s a beautifully simple way to explain a problem that had a lot of physicists thinking we needed whole new laws of physics.
如果他们的说法是正确的，那么这种方法就非常简单，可以解释很多物理学家的困惑，让他们不必执着于猜想新的物理学法则。
But we’ll have to wait and see if it gets accepted by the scientific community.
但我们还要观望这种说法是否能为科学界所接受。
The researchers don’t really have strong reasons to think that the plasma wouldn’t be in equilibrium; they just say that it’s plausible.
研究人员没有确凿的证据可以说明等离子体确实处于平衡状态，他们只是认为这种说法是可行的。
And their model also doesn’t predict anything new; it just matches what we already know, which makes it hard to test.
他们的模型也没有预测出新的情况；只是与我们已经知道的信息相吻合罢了，这就让验证工作变得很难。
We should just keep running the Big Bang over again...take some measurements...just...you know...more Big Bangs!
我们还是应该再一次过一遍宇宙大爆炸的过程，进行测量，然后反复如此。
The authors end the paper by encouraging more research into this new model to see if it predicts anything else that we haven’t seen yet about the universe’s first few minutes.
本文结束时，作者鼓励对该新建模进行更多的研究，以查验该模型是否还发现了宇宙初期几分钟内我们还没有发现的情况。
They also point out that the insides of stars might be out of equilibrium in a similar way, so research into those types of plasmas could lead to other predictions that scientists can go out and test.
本文作者还指出，恒星内部可能也以相同的方式平衡着，所以对这些等离子体类型的研究可以得出其他的预测结果，以便科学家进行验证。
And if it does, maybe we’ll have an update to that list of mysteries about the universe sooner than we thought.
如果当真如此，或许我们就可以以更快的速度来解决当前的宇宙谜题了。
Thanks for watching this episode of SciShow Space News.
感谢收看本期的《太空科学秀》。
One of our favorite parts of space is the Earth!
我们对宇宙里最感兴趣的部分当然是地球啦！
It’s a really great planet and April 22 is Earth Day this year.
地球是个很棒的星球，而今年的4月22日就是地球日哦。
And on Earth Day, the March for Science is taking place in Washington, D.C. and all over the US.
地球日这天，华盛顿内乃至整个美国都会进行科学游行。
To show our support for scientists and their work making the world a better place and understanding it better,
为了力挺让世界更好、让人们更懂世界的科学家们，
we made these “Knowledge is Power” shirts and posters that we think are great for any day, but if you want one before April 22, make sure you order yours today!
我们只做了“知识就是力量”的T恤和海报，不仅适用于地球日这天，但如果大家想在4月22日之前得到T恤和海报的话，今天就要预定哦！
There’s a link in the description. And if you want to keep getting smarter along with us, don’t forget to go on to youtube.com/scishowpace and subscribe.
描述里有预定链接。如果大家想跟我们一起学习的话，不要忘记订阅youtube.com/scishowpace哦。
