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The Cassini probe has been orbiting Saturn for almost thirteen years, and in that time it's sent back some of the most incredible pictures and data we've ever seen.
卡西尼号环绕土星已有近30年的时间，在此期间，它传回了一些珍贵的图片和数据。
It's found underground oceans on Enceladus, methane lakes on Titan, mysterious hexagons at Saturn's poles, and so much more.
卡西尼号发现土卫二上有地下海，土卫六上有甲烷，土星的极点伤有神奇的六边形等等。
Its mission ends in September, when it'll dive down into Saturn's clouds in a blaze of glory.
卡西尼号将于9月结束使命。届时，它将带着辉煌的光芒穿越土星云层坠落。
But Cassini still has a lot to do in the meantime.
但卡西尼号目前还是身负重任的。
It just finished a risky dive between Saturn and its ring's -- something no probe has ever done before.
卡西尼号刚刚完成土星及土星光环之间的一次冒险穿越——这是其他探测器未曾做过的一件事。
And it'll repeat the trick 21 more times before September.
而且在9月之前，这样的事情，它还要再做21次。
Sending Cassini through the rings will let scientists map Saturn's gravity and magnetic fields like never before, because nothing else has ever gotten this close.
通过让卡西尼号穿越土星光环可以让科学家前所未有地勾勒出土星的重力场和磁场，毕竟未曾有探测器可以离土星这样近。
It was just too dangerous.
唯一的问题在于太过危险。
The rings are made of rocks and ice moving dozens of kilometers a second, so they aren't the safest place for a spacecraft with lots of sensitive electronics.
土星光环是由石头和冰组成的，它们的移速都达到了每秒数十千米。所以，土星光环对于载有许多敏感电子器件的航天器来说并不是最安全的地方。
Cassini did fly through the 30,000-kilometer gap between the inner and outer rings when it first got to Saturn in 2004.
2004年，卡西尼号首次抵达土星后，确实穿越了内外环之间的3万千米。
But we only sent it through that big gap because we already knew it was pretty empty.
但我们是在知道内外环之间空无一物后才决定发射卡西尼号的。
Now that the mission is finally winding down, there's not much left to lose.
现在，鉴于任务量逐渐减少，所以也可以放手一搏了。
So it's time to send Cassini on some way more dangerous dives.
现在是时候派卡西尼号去执行更危险的任务了。
The plan is to thread the needle between Saturn and its innermost ring 22 times.
我们计划将在土星及其最内环之间实现22次往返。
That gap is ten times smaller than the gap it went through back in 2004.
土星及其最内环之间的距离是2004年所穿梭距离的1/10。
Cassini finished its first dive last week, but there were a few tense hours back here on Earth when we weren't sure if it made it through.
上周，卡西尼号完成了第一次飞行，不过在我们不确定它是否安然渡过的时候，确实担心了几个小时。
The probe used its dish-shaped antenna as a shield, just in case anything was in its path, but that also meant that it couldn't let us know if it survived until about 20 hours after it passed through the rings.
卡西尼号将盘形的天线作为防护，以防有其他物体与它相撞，不过这也意味着我们无法得知它是否安然无恙，只能等20个小时候见分晓。
Cassini made it, though, and collected data the whole trip!
卡西尼号不仅安然无恙，还全程收集了数据！
Since we've never sent anything through that gap before, hopefully we'll learn some totally new things about Saturn and its rings.
鉴于我们之前从未派任何探测器做过这样的事情，所以我们希望能了解到以前未曾了解的有关土星及其光环的信息。
A lot of the data will take a while to process, but Cassini already sent back a few of those incredible photos that we've all gotten used to for the last 13 years.
鉴于数据较多，处理起来还需要一段时间。不过卡西尼号已经发回了一些珍贵的照片，这些照片是我们过去13年来习以为常的景象。
Like this close-up of a storm on Saturn.
比如，土星风暴的特写。
Pictures like that will keep flooding in over the next few months, telling us more about how Saturn's atmosphere moves and evolves.
类似这样的照片会在未来的3个月里铺天盖地，让我们对土星大气层的移动和演变了解的更多。
In the process, we're getting perspectives on Saturn and on the entire solar system that no one has ever seen before, which is a pretty cool. And bonus: gorgeous!
在这个过程中，我们对土星以及整个太阳系有了更多的了解，这是一件很酷的事情。福利也很惊人哦！
Speaking of new perspectives on the solar system:
说到对太阳系的最新认知：
Last week, a team of researchers published a paper in the journal Nature claiming that the Sun's surface might not be quite as complicated as astronomers thought.
上周，一组研究人员在《自然》期刊上发表了一篇论文，指出太阳表面可能并不像天文学家想的那样复杂。
The Sun has two main kinds of eruptions where particles shoot out from its surface: Coronal Mass Ejections, or CMEs, and coronal jets.
太阳表面有两种主要的喷发形式：日冕物质抛射(CME)以及太阳大气喷流。
CMEs are the big ones that we need to watch out for.
前者规模很大，是我们需要注意的。
Each one launches billions of tons of plasma at millions of kilometers an hour, and they can endanger astronauts and interrupt communications around the world if they hit Earth.
无论是哪种喷发形式都会释放无数的高速等离子体，这些等离子体会威胁宇航员的安全，而且如果它们撞击地球的话，还会干扰宇航员与地球之间的交流。
Coronal jets also fire out plasma, but they're way smaller and have much less energy.
太阳大气喷流也会释放等离子体，但它的规模和能量都更小。
Astronomers have known for a while that both kinds of eruptions involve the Sun's magnetic fields twisting and crashing into each other until plasma breaks free and flies off into space.
此前，天文学家就已经知道，无论是哪种喷发形式，太阳的磁场都会发生扭缠和撞击，直到等离子体突出重围，飞向太空。
But for years, they thought that's where the similarities ended.
但多年来，科学家一直以为这就是这两种喷发形式的唯一共同点了。
It didn't seem like the same kind of twisting and splicing could make both giant, explosive CMEs and those smaller jets.
似乎磁场以同一种方式扭缠和拼接并不会引发两种喷发。
As astronomers studied more eruptions, though, they discovered that they're actually really similar — so similar that there's probably one main process causing both CMEs and coronal jets. Just on different scales.
天文学家对喷发了解的越多，就越发现这两种喷发其实非常相似——正因为它们太过相似，所以很有可能是同一种过程引发了这两种喷发。只不过它们规模不同罢了。
So this group of researchers used simulations to try and figure out what kind of twisting in the Sun's magnetic fields could cause both types of eruptions.
所以，这组研究人员通过模拟来尝试弄清楚太阳磁场的何种扭缠会引发两种喷发。
They decided to try simulating mini-CMEs, way smaller than the ones we see on the Sun.
它们决定尝试模拟小型的日冕物质抛射，即规模小很多的日冕物质抛射。
The fields in regular CMEs stretch over big sections of the Sun and have huge loops of plasma that eventually explode out when the magnetic fields get twisted together and rearranged.
常规日冕物质抛射的磁场会覆盖太阳的许多区域，并形成巨大的等离子体环，这些环最终爆发，磁场扭缠在一起，重新排布。
So the team tried shrinking down the fields to see if the process that causes CMEs would produce something like a jet on a smaller scale.
所以，该小组尝试压缩磁场，看看引发日冕物质抛射的过程是否会产生较小规模的太阳大气喷流。
And it did! They found that even with the same sorts of things happening to the magnetic fields as in big CMEs, the resulting eruption looked pretty different on a smaller scale.
事实也确实如此。他们发现，即便用大规模日冕物质抛射中磁场遭遇的同种要素，最终的喷发也是规模更小的喷发形式，与日冕物质抛射大为不同。
As the magnetic fields twisted, the plasma got pushed together instead of spreading apart.
随着磁场的扭缠，等离子体不但没有四散开来，反而冲撞在一起。
And when it finally broke free as the fields rearranged, it all rushed out along a single line -- just like what we see in coronal jets.
然后，随着磁场的重新排布，等离子体会沿着一条线喷发出去——就像太阳大气喷流一样。
If this is really what's happening on the Sun, that means the only real difference between gigantic CMEs and those smaller jets is the strength of the magnetic fields involved.
如果这就是太阳表面发生的情况的话，也就意味着两种喷发形式的唯一不同就在于：磁场的强度不同。
Big fields tend to spread out and make CMEs, while small fields clump together to form jets.
强磁场倾向于通过四散来产生日冕物质抛射，而小磁场则会通过聚合来产生太阳大气喷流。
We're still not sure if this is actually what happens, since these are just simulations.
我们还不知道这是否就是现实的情况，毕竟这只是模拟。
But if it is, then we now have one unified theory to explain all kinds of eruptions.
但如果这就是现实情况，那么我们现在就有统一的理论来解释各种喷发形式了。
And that makes it a lot easier to study and compare them.
那么以后研究比较不同喷发形式的难度也就降低了。
Either way, we're one step closer to understanding the giant, and sometimes dangerous, explosions bursting out of the Sun.
无论是哪种情况，我们都离研究太阳喷发现象更近了一步。
And hopefully someday we'll be able to use that understanding to make better predictions about when they'll happen, and give ourselves a few precious extra moments if a massive CME is about to head right for us.
希望以后我们能通过所知来更好地预测太阳喷发的时间点，在日冕物质抛射发生在我们眼前时，可以有时间留下宝贵的时刻。
Thank you to our patrons on Patreon for helping make this show possible.
感谢粉丝们支持我们的节目。
If you want to help us keep making episodes like this, you can go to patreon.com/scishow.
如果大家想助力我们制作类似本期的视频的话，就请登录patreon.com/scishow吧。
And if you want to watch more episodes like this, there's probably some in the side bar. It's actually on that side…
如果您想要看更多类似的集锦，在侧栏会有惊喜哦。其实就是这边啦。
And if you want to subscribe and watch a new one, twice a week, that would also be great, at youtube.com/scishowspace … or just there's a button under the video.
而如果您想要订阅并观看两周一次的节目的话，那自然是好事啦！就请关注youtube.com/scishowspace吧……视频下方也有订阅按钮哦！
