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The International Astronomical Union defines Brown Dwarfs as balls of gas in space that are too small to be bona-fide hydrogen-burning stars,
国际天文学联合会将褐矮星定义为太空中的气球，它们太小，不可能是真正的氢燃恒星，
but large enough to burn deuterium, which anything bigger than about 13 times the mass of Jupiter can do.
但又大到足以燃烧氘，任何大于木星质量约13倍的东西都可以燃烧氘。
Because of this, brown dwarfs are often called “failed stars” or “super Jupiters.”
正因为如此，褐矮星通常被称为“失败的恒星”或“超级木星”。
However, there’s a major problem with this deuterium-burning-based definition: it doesn’t make any scientific sense.
然而，这种以烧氘为基础的定义有一个主要问题：它没有任何科学意义。
First, unlike how hydrogen fusion is huge since it means you can shine brightly for millions or billions of years,
首先，与氢聚变的巨大不同，因为它意味着你可以发出数百万年或数十亿年的明亮光芒，
burning deuterium doesn’t appear to affect an astronomical object in any particularly meaningful way, which is probably why you haven’t heard much about it.
燃烧氘似乎不会以任何特别有意义的方式影响天文物体，这可能就是为什么你对它知之甚少的原因。
I mean, on this density vs mass plot, hydrogen burning is a cutoff that clearly distinguishes stars from non-hydrogen-burning things, while deuterium burning doesn’t appear distinguishing at all.
我的意思是，在这个密度与质量的曲线图上，氢燃烧是恒星与非氢燃烧物体的明显区别，而氘燃烧似乎完全没有区别。
So it may seem like there is no distinction between things that are slightly-too-small to be stars (which we call brown dwarfs) and giant gas planets, and that they’re all really the same kind of object.
因此，看起来小到不可能是恒星(我们称之为褐矮星)的东西和巨大的气体行星之间似乎没有区别，它们实际上都是同一类物体。
However, just because deuterium isn’t a good cutoff doesn’t mean there aren’t other options.
然而，仅仅因为氘不是一个好的区分点并不意味着没有其他选择。
So, let’s briefly list the features that DO scientifically distinguish brown dwarf-like objects from gas-giant-like objects
所以，让我们简单地列举一下在科学上区分褐矮星类天体和类气态巨星类天体的特征
(And a caveat here: some of these statements are still being debated within the astronomical community, but for each one there are at least some researchers arguing in favor of it):
(这里还有一个警告：其中一些说法在天文学圈子里仍在争论，但对于每一种说法，至少都有一些研究人员支持它)：
1.Movement: Brown dwarfs (whether above or below the deuterium limit) and stars appear to be located and move in similar ways: in loose clusters with other similar objects moving with roughly the same relative speeds.
1.运动：褐矮星(无论是在氘的极限之上还是之下)和恒星似乎以相似的方式定位和运动：与其他类似物体以大致相同的相对速度移动在松散的星团中。
Planets, on the other hand, move around stars in orbits, and are much closer to the nearest star – which can even be a brown dwarf.
另一方面，行星围绕恒星运行，距离最近的恒星更近，甚至可能是褐矮星。
2.Formation: Brown dwarfs (whether above or below the deuterium limit) and stars appear to follow the same distribution of masses,
2. 形成：褐矮星(无论是在氘极限之上还是之下)和恒星似乎遵循相同的质量分布，
suggesting they form the same way: the gravitational collapse of a cloud of gas and dust.
这表明它们的形成方式是相同的：气体和尘埃云的引力崩塌。
Planets appear to follow a different distribution of masses,
行星似乎遵循着不同的质量分布，
suggesting they form in their own way: by accreting from the protoplanetary disk of gas and dust leftover around a star (or brown dwarf) after it forms.
表明它们是以自己的方式形成的：在恒星(或褐矮星)形成后，由恒星(或褐矮星)周围残留的气体和尘埃组成的原始行星盘吸积而成。
3. Metallicity: The dust and gas leftover from star formation has higher concentrations of metal, so the atmospheres of gas giant planets have elevated levels of metal.
3. 金属性：恒星形成后残留的尘埃和气体含有较高浓度的金属，因此气态巨行星的大气中金属含量较高。
Brown dwarfs (whether above or below the deuterium limit) have around the same amount of metal as stars.
褐矮星(高于或低于氘极限)的金属量与恒星大致相同。
4.Size of Orbits: Protoplanetary disks around stars typically don’t extend much farther than a few hundred times the distance between the earth and the sun, so that’s about as far out as you find planets.
4. 轨道大小：围绕恒星的原行星盘通常不会延伸到地球和太阳之间距离的几百倍，所以这大约是你发现行星的距离。
However, brown dwarfs (whether above or below the deuterium limit) often orbit stars or other brown dwarfs in binary pairs at significantly greater distances .
然而，褐矮星(无论是高于或低于氘的极限)通常以更大的距离围绕恒星或其他成对运行的褐矮星运行。
5. Mass Ratio: Protoplanetary disks are pretty much never more than 10% of the mass of their parent star (or brown dwarf), so a planet-to-star mass ratio is almost always more extreme than 1 to 10.
5.质量比：原行星盘几乎从来不会超过其母恒星(或褐矮星)质量的10%，因此行星与恒星的质量比几乎总是比1：10更极端。
However, brown dwarfs (whether above or below the deuterium limit) and stars regularly orbit in pairs with mass ratios much closer to 1 to 1, suggesting they formed from their own clouds of gas and dust.
然而，褐矮星(无论高于或低于氘的极限)和恒星经常成对运行，质量比更接近1：1，这表明它们是由自己的气体和尘埃云形成的。
Basically, a lot of evidence points to two separate populations of objects: things that form from gravitationally collapsing clouds of gas, and things that form from the leftovers.
基本上，很多证据指向两类不同的物体：一类是由引力崩塌的气体云形成的，另一类是由残余物形成的。
It appears an unfortunate coincidence that the overlap in these two populations is roughly at the mass where deuterium-burning becomes possible.
这似乎是一个不幸的巧合，这两个群体的重叠大致是在可能燃烧氘的地方。
I mean, IF we didn’t have any other good ways to distinguish between brown dwarfs and planets, sure, deuterium burning might be a reasonable rule of thumb.
我的意思是，如果我们没有任何其他好的方法来区分褐矮星和行星，当然，燃烧氘可能是一个合理的经验法则。
It’s also possible, as some researchers contend, that there IS no real, clear way of distinguishing between brown dwarfs and giant planets, and that they really do just exist on a spectrum.
也有可能，正如一些研究人员所说，没有真正、明确的方法来区分褐矮星和巨行星，它们确实存在于光谱上。
But either way, deuterium is more or less a distraction.
但不管怎样，氘或多或少会让人分心。
So, among those who think that the evidence suggests brown dwarfs are different from giant planets, what supposedly distinguishes them is how they formed, their consequent behavior, and their composition.
因此，在那些认为证据表明褐矮星与巨行星不同的人中，据推测它们的不同之处在于它们是如何形成的，它们随后的行为，以及它们的组成。
The claim is this: planets, no matter how big, appear to be the leftovers of star formation.
这种说法是这样的：行星，无论有多大，似乎都是恒星形成的剩余物。
And brown dwarfs, no matter how small, appear to be failed stars: they started off the same ways stars do by gravitationally collapsing from a cloud of dust, but failed to capture enough mass to burn hydrogen.
而褐矮星，不管有多小，看起来都是失败的恒星：它们开始的方式与恒星一样，是通过从尘埃云中引力坍塌开始的，但它们未能捕获足够的质量来燃烧氢气。
Perhaps in the end it doesn’t matter how badly they failed –?
也许到最后，褐矮星一败涂地也无关紧要--？
That is, it doesn’t matter if they also can’t burn deuterium – what matters is that they aspired to be stars, and fell short.
也就是说，它们是否能燃烧氘并不重要——重要的是，它们渴望成为恒星，但没有达到目标。
Thanks to NASA’s James Webb Space Telescope Project at the Space Telescope Science Institute for supporting this video.
感谢NASA太空望远镜科学研究所的詹姆斯·韦伯太空望远镜项目对本期视频的支持。
JWST is literally the perfect telescope for studying brown dwarfs: it sees best in infrared light, and guess what brown dwarfs mostly emit: yup, infrared!
詹姆斯·韦伯太空望远镜实际上是研究褐矮星的完美望远镜：它在红外光下看得最清楚，猜猜褐矮星主要发射的是什么：是的，红外线！
Unlike stars which are super hot, the smallest brown dwarfs are about the same temperature as you and me, and they give off infrared light right in the middle of JWST’s spectrum.
与超热的恒星不同，最小的褐矮星与你我的温度大致相同，它们发出的红外线正好位于詹姆斯·韦伯太空望远镜光谱的中间。
This also means that if you and I were in space, we’d shine out like a beacon to JWST even with no stars nearby.
这也意味着，如果你和我在太空中，即使附近没有恒星，我们也会像灯塔一样向詹姆斯·韦伯太空望远镜发出光芒。
So JWST will be able to find and study human-temperature brown dwarfs and compare them with super Jupiters to help settle the brown dwarf debate.
因此，詹姆斯·韦伯太空望远镜将能够发现和研究与人类温度相同的褐矮星，并将它们与超级木星进行比较，以帮助解决关于褐矮星的争论。
