(单词翻译:单击)
This episode is sponsored by The Ridge.
本期节目由The Ridge赞助。
Go to ridge.com/scishow and use promo code “scishow” to get 10% off your next order.
登录ridge.com/SciShow，使用“scishow”优惠码，下次订购可以享受10%的优惠。
The universe is an awfully big place, so astronomers rarely get as close to things in space as they’d like.
宇宙是一个非常大的地方，所以天文学家们很少能如愿以偿地接近太空中的物体。
One way around this problem is to test ideas using computer simulations, which are informed by our understanding of nature.
解决这个问题的一种方法就是用计算机模拟来测试我们的想法，这些想法是由我们对自然的理解决定的。
And last week, two studies came out that took this approach to try and better understand planets outside our solar system and how they form.
上周，有两项研究采用了这种方法，试图更好地了解太阳系以外的行星以及它们是如何形成的。
The first was published in the Monthly Notices of the Royal Astronomical Society: Letters, and it explores so-called Peter Pan disks.
第一篇研究发表在《皇家天文学会月报:快报》上，它探索了所谓的彼得潘圆盘。
These objects are unfortunately not home to a hook-wielding space pirate;
不幸的是，这些物体并不是手持弯钩的太空海盗的家;
instead, they are protoplanetary disks that seemingly never grow up.
相反，它们是似乎永远都不会长大的原行星盘。
Protoplanetary disks are disks of gas and dust that surround young stars.
原行星盘是围绕年轻恒星的由气体和尘埃组成的盘。
And through a process that scientists still don’t totally understand, out of these disks grow the planets, moons, asteroids, and comets that make up a solar system.
通过一个科学家还无法完全了解的过程，这些圆盘诞生出了行星、卫星、小行星和彗星，它们组成了太阳系。
This is a fast process, as far as things in space are concerned.
从太空的角度来看，这个过程很快速。
Most protoplanetary disks last only a few million years, and virtually all of them have disappeared after 10 million years.
大多数原行星盘只存在几百万年，几乎所有的原行星盘都在1000万年后消失了。
But in 2016, citizen scientists helped astronomers identify a disk around a star that appears to be 45 million years old, and since then, several more of these “Peter Pan disks” have been found.
但在2016年，民间科学家帮助天文学家确定了围绕一颗恒星的一个圆盘，它似乎有4500万年的历史，从那以后，又发现了几个这样的“彼得潘圆盘”。
This new study tries to explain how these objects could last so much longer than others.
这项新研究试图解释为什么这些物体能够比其他物体保存更长时间。
Using a computer model, they simulated star-forming regions with a range of conditions to figure out which attributes lead to Peter Pan disks.
利用计算机模型，他们模拟了一系列条件下的恒星形成区域，以找出导致彼得潘圆盘形成的原因。
And the results suggest that two factors are especially important.
研究结果表明，有两个因素尤为重要。
The first is what’s going on around a forming disk.
第一是圆盘周围的情况。
Most stars form in large clumps that often contain 100,000 stars or more packed close together.
多数恒星会形成大团块，里面通常包含10万颗或更多的恒星，它们紧密地挤在一起。
But those environments are also dense, with lots of stellar radiation that can cause protoplanetary disks to evaporate away.
但这些环境也很密集，有大量的恒星辐射会让原行星盘蒸发掉。
So Peter Pan disks need to be loners to survive.
所以彼得潘圆盘需要独处才能生存。
The disks also need to start off being extremely large. Which kind of makes sense.
圆盘一开始也需要非常大。这是有道理的。
A disk that starts off with a lot of material can afford to lose more than usual.
一个一开始就含有大量物质的圆盘可以承受比平常更多的损失。
But this also helps explain a curious feature of Peter Pan disks, which is that so far, they’ve only been found around low-mass stars.
但这也有助于解释彼得潘圆盘的一个奇怪特征，那就是到目前为止，它们只在低质量恒星周围被发现。
Now, this could be a sampling error, but the authors suggest it could also be that high-mass stars are just more likely to form in those dense groups of stars, where Peter Pan disks are less likely.
这可能是采样错误，但作者认为也可能是因为大质量的恒星更有可能在那些密集的恒星群中形成，而那里不太可能形成彼得潘圆盘。
As with other modeling studies, astronomers will need to see a lot more Peter Pan disks to confirm that these ideas hold up, but their existence alone is a reminder of how variable the process of planet formation is.
和其他的建模研究一样，天文学家需要发现更多的彼得潘圆盘来证实这些观点，但它们的存在本身就提醒我们行星的形成过程是多么的多变。
The second study last week was published in Nature Communications, and this one looked at another aspect of planets around small stars: their habitability: that is, whether life as we know it could survive there.
上周的第二篇研究发表在《自然通讯》上，这项研究着眼于小恒星周围行星的另一个方面:它们的宜居性:即我们所知的生命是否能在那里生存。
Or technically, it’s where liquid water could stably exist on the surface, which accomplishes approximately the same goal.
或者从技术上来说，液态水可以稳定地存在于火星表面，这可以达到大致相同的目的。
Many planets around dwarf stars are tidally locked, which means that the same side of the planet always faces the star.
许多围绕着矮恒星的行星都会被潮汐锁住，这意味着行星总是同一面朝着恒星。
As you can imagine, somewhere where it’s either always day or always night doesn’t seem like an ideal place to live.
你可以想象，一个要么整天都是白天，要么整天都是夜晚的地方似乎并不是理想的居住地。
The side facing the star often heats up dramatically, while the far side can be extremely cold.
面对恒星的那一面通常会急剧升温，而远离恒星的那一面则可能极其寒冷。
But in computer simulations run by the authors of this paper, they suggest there might be an antidote: dust.
但是在这篇论文的作者所进行的计算机模拟中，他们指出可能存在一种解决方法:灰尘。
Dust may sound mundane, or even like a bad thing.
灰尘可能听起来很普通，甚至不是个好东西。
But the effects of dust on climate are much more nuanced than you might expect.
但是灰尘对气候的影响比你想象的要微妙得多。
On Earth, the main role of high-altitude dust, so far as we can tell, seems to be in cooling the planet.
在地球上，据我们所知，高海拔尘埃的主要作用貌似是冷却地球。
As light reaches the Earth from the Sun, some of it hits particles of dust and is reflected back into space.
当阳光从太阳照射到地球上时，其中一些会撞击到尘埃颗粒，然后被反射回太空中。
That’s why volcanic eruptions can have a measurable impact on the Earth’s average temperature.
这就是为什么火山爆发会对地球的平均温度产生重大影响。
But dust doesn’t just cool the planet, it also warms it up.
但尘埃不仅能使地球变冷，也能让它变暖和。
See, planets radiate heat, and some of that heat gets absorbed by dust and is trapped in the atmosphere before it can escape to space.
行星辐射热量，其中一些热量被尘埃吸收，在它逃到太空之前被困在大气中。
Overall, though, our current understanding is that dust cools our planet more than it warms it up.
总的来说，我们目前的理解是，灰尘对地球的冷却作用大于它对地球的升温作用。
But on some tidally-locked exoplanets, the researchers suggest the picture might be more complicated.
但在一些潮汐吸引的系外行星上，研究人员认为情况可能更为复杂。
Their simulations indicate that on the day side of a planet, atmospheric dust cools more than it heats.
他们的模拟表明，在行星上的白天，大气尘埃冷却的比变热的多。
But on the night side, the opposite happens.
但在夜晚，情况正好相反。
The net effect on the planet is one of moderation.
它对行星的影响基本互相抵消了。
The hot, day side ends up cooler than it would be otherwise, while the cold, night side gets a bit warmer.
白天炎热的那一面会比平时更冷，而夜晚寒冷的那一面会稍微暖和一点。
So with smaller temperature extremes, some of these planets might actually be more habitable than astronomers would initially think.
因此，在温度极限较小的情况下，这些行星中的某些或许比天文学家最初认为的更适合居住。
The big picture here is that the universe is, as usual, more complicated than we like to assume.
整体情况是，宇宙通常比我们想象的要复杂得多。
If we rely on broad statements like “protoplanetary disks are short-lived” or “tidally-locked worlds aren’t habitable,” we’ll be missing the nuance we might really need to understand what’s really goin’ on.
如果我们依赖诸如“原行星盘寿命较短”或“潮汐吸引的星球不适于居住”这样宽泛的声明，我们将会错过那些可以帮助我们搞清楚到底发生了什么事情的细微差别。
Fortunately, computer simulations can help scientists identify their blind spots by testing their ideas with scenarios we haven’t seen in nature.
幸运的是，计算机模拟可以通过我们在自然界中从未见过的场景来测试科学家们的想法，从而帮助他们识别盲点。
Which, hopefully, will result in faster progress and more new discoveries.
希望这能带来更快的进展和更多的新发现。
Thanks for watching this episode of SciShow Space News!
感谢收看本期太空科学秀!
This week’s episode is brought to you by the folks at The Ridge, makers of The Ridge Wallet.
本周的节目是由The Ridge公司的员工为您带来的，他们是The Ridge钱包的制造商。
They’re making a thin, light wallet that’s designed to fit in your pocket easily, and to carry up to a dozen cards plus cash without bulging.
他们正在制造一款轻薄的钱包，可以轻松放进口袋，并且可以携带多达12张卡和现金而不会鼓起来。
They also come with a lifetime warranty.
钱包享有终身保修。
If you’re interested in trying one out, The Ridge team is offering a 45-day trial where you can test the wallet and see what you think.
如果你有兴趣试用一下，Ridge团队提供了为期45天的试用期，你可以试用一下钱包，看看感受如何。
And if you’re not a fan, you can return it for a full refund.
如果你不喜欢，也可以全额退款。
To learn more, go to ridge.com/SCISHOW.
想了解更多，请登录ridge.com/SCISHOW。
And if you want a wallet, you can get 10% off and free worldwide shipping by using the promo code “SCISHOW.”
如果你想买钱包，使用“SCISHOW”的优惠码，可以享受10%的优惠，并且全球免费送货。
