It's a puzzle that has bedeviled astronomers and theorists for years: Do massive stars form in the same way as our sun or by some other process? Now a team of astronomers has gone a long way toward providing the answer by catching a massive star in the act of condensing. Their verdict is that this massive star, at least, seems to follow th e same mechanism as smaller stars.

 这是一个困惑了天文学家和理论家多年的谜：巨型恒星跟我们的太阳是以同样方式形成的吗？莫非巨型恒星是以其他方式形成的？目前，一组天文学家经过长期努力，拍摄到一颗正在凝缩中的巨型恒星，找到了问题的答案。他们得出的结论是：起码这颗恒星好象跟较小的恒星遵循着相同的形成机制。

 Based on decades of observations, astronomers know that sun-sized stars condense from vast clouds of dust and gas. But finding nascent massive stars has proven difficult. They are rare and form within just a few hundred thousand years, so it's unlikely that astronomers will spot one that is condensing and close enough to observe. Also, no star, heavy or light, forms out in the open. They are born in a cosmic womb of obscuring dust and gas, which prevents optical observations altogether and makes studies in other wavelengths tricky.

 根据几十年的观测，天文学家们知道象太阳这么大的恒星是从大团的尘埃和气体凝缩而来。但是事实证明，要想发现刚刚诞生的巨型恒星是艰难的。这种恒星很稀少，而且仅仅形成于几十万年之内，因此天文学家们不可能发现正在凝缩中的、距离近而又便于观察的恒星。况且，不管质量大与小，任何恒星都不会形成于视野开阔的太空中，相反它们诞生于宇宙中尘埃和气体的发源地，那里朦朦胧胧，xx遮挡了观察视线，使得在其他波长下的观察难以进行。

 So the researchers used a new tool--the Near-Infrared Integral Field Spectrograph (NIFS) on the Gemini North telescope at Mauna Kea, Hawaii--to study one of the few, well-known, young and massive stars. With its ability to detect infrared light, NIFS pierced the gas and dust obscuring the star, known as W33A and located about 12,000 light-years away in the constellation Sagittarius. The detailed spectrum of the light allowed the astronomers to measure the relative speed and direction of motion of the material surrounding W33A.

 因此，研究小组使用了一种新工具来研究xxxx的几颗xx的年轻xx之一，这种新工具是夏威夷莫那克亚山上双子北座望远镜上安装的近红外全视角光谱仪（NIFS），该工具有探测红外光的能力，穿透了笼罩着那颗恒星的气体和尘埃。该恒星被称为W33A，大约在12,000光年之外，位于人马座。恒星光线的详细光谱使研究人员能够测出W33A周围物质运动的相对速度和方向。

 The team found that W33A, which is about 10 times more massive than the sun, not only is surrounded by a disk of gas and dust from which it's condensing but is also ejecting fast-moving jets of particles from its north and south poles. As the team in an upcoming Monthly Notices of the Royal Astronomy Society, the disk and the jets are very similar to what is seen around young, low-mass stars. Moreover, the jets are the "smoking gun" that W33A is still growing, says astronomer and lead author Ben Davies of the University of Leeds in the United Kingdom. The next step, he says, is to see whether the jets are common to all massive protostars.

 研究小组发现，W33A的质量比太阳大10倍，其周围不仅有一个凝缩的气体和尘埃圆盘，而且从它的南北两极还喷出高速运动的粒子射流。研究小组在即将出版的《皇家天文学会月报》上报道：圆盘和射流非常类似于在年轻的低质量恒星周围所看到的情况。英国利兹大学的天文学家、研究论文的{dy}作者本·戴维斯说：而且，这些射流是确凿的证据，说明W33A正在成长。他说，下一步要看看射流对于大型原恒星来说是不是普遍现象。

 The observations are "beautiful," says astronomer Scott Kenyon of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. They "clearly show that at least some massive stars grow by accreting material from a circumstellar disk of gas and dust, just like our sun did roughly 4.5 billion years ago." The finding is "an exciting new result that further strengthens the case for a universal mechanism of star formation," says astronomer Jonathan Tan of the University of Florida, Gainesville. One question, Tan says, is how efficiently the process works for massive versus light stars, because that's likely to be the mechanism that determines stellar mass.

 马萨诸塞州剑桥市哈佛-史密森天体物理中心的天文学家斯科特·凯尼恩说：“这些观察资料很棒，明确地说明至少有一些巨型恒星是通过吸积环恒星盘中的气体和尘埃而成长的，正象我们的太阳在大约45亿年前的情况一样。”佛罗里达大学（位于盖恩斯维尔市）的天文学家乔纳森·坦恩称，该发现是个令人兴奋的新成果，进一步强调了这个情况是恒星形成的普遍机制。然而坦恩说，问题是：巨型恒星跟小型恒星相比吸积过程的运行效率有什么差别呢？因为这个问题可能是决定恒星质量的机制。