Barnard 68

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At a distance of only 410 light-years, Barnard 68 is one of the nearest dark clouds, a so-called "Bok globule". Its size is about 12,500 AU (= 2 million million km), or just about the same as the so-called "Oort Cloud" of long-period comets that surrounds the solar system. The temperature of Barnard 68 is 16 Kelvin (-257 _C) and the total mass of the cloud is about twice that of the Sun.By means of instruments at the Very Large Telescope at Paranal, astronomers found a total of about 3700 background stars (of which over 1000 can only be seen at infrared wavelengths).Careful measurements of the colours of these stars and hence, the degree of obscuration, allowed the most finely sampled and most accurate mapping of the dust distribution inside a dark cloud ever performed. It was found that this dependance is almost exactly as that predicted for a sphere in which the opposite forces of gravity and internal pressure closely balance each other. Nevertheless, it is also evident that Barnard 68 is only marginally stable and is on the verge of collapse. The astronomers suggest that Barnard 68 may be the precursor of an isolated and sparsely populated association of low-mass solar-like stars.

我用google翻译的，不太准确：
在距离仅410光年，巴纳德68是最接近的乌云，一个所谓的“福球” 。它的大小约为12500 1.00 （ = 200万万公里） ，或只是一样的所谓的“奥尔特云”长周期彗星围绕太阳系。温度巴纳德68 16开尔文（ -257 _C ）和总重量的云的两倍左右，在Sun.By手段文书甚大望远镜在帕拉，天文学家共发现了约3700背景星级（其中超过1000只能看到红外线波长） 。仔细测量颜色的这些恒星，因此，在一定程度的朦胧，使最精细采样和最准确的测绘尘埃分布在一个乌云以往任何时候都表现。有人认为，这依赖几乎是完全一样的预测的领域中相反的力量的严重性和内部的压力密切彼此的平衡。然而，同样显而易见的是，巴纳德68只稍微稳定，并处于崩溃的边缘。天文学家认为巴纳德68可能是前一个孤立的和人口稀少协会低质量的太阳能明星。

哇，一坛污水啊。

这到底是什么？

巴纳德暗星云有好多呢！