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Peering deep into the Milky Way galaxy, astronomers might have solved the decades-old mystery of how gigantic stars emerge. Based on the new observations, it seems that stars can start to grow huge when interstellar turbulence prevents the formation of any other stars nearby. |
天文学家们凝视了银河系的深邃之处后，解开了一个困惑他们长达几十年的谜团——巨型恒星的形成之谜。根据新一轮观测，他们发现情况好象是这样的：当星系间的动荡状态阻止了附近其他恒星的形成时，恒星就开始发展为巨型恒星。 |
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The sun might seem gigantic and powerful from Earth, but it's downright puny compared to behemoths such as Betelgeuse, which is about 600 light-years away. If Betelgeuse switched places with the sun, its atmosphere would graze Mars. Regardless of size, all stars are thought to emerge in the same basic way: Gravity contracts a giant, diaphanous cloud of gas and dust and eventually ignites a star's nuclear furnace. But how do relatively rare titans such as Betelgeuse emerge from the same stuff that usually yields batches of sun-sized orbs and even more common red dwarfs? |
从地球上来看，太阳看起来巨大而有威力，但是跟象参宿四那样的庞然大物相比，太阳就根本微不足道了。参宿四位于600光年以外，如果将参宿四和太阳易位，参宿四的大气就会扫过火星。不管大小，所有的恒星都被认为是以同样的方式诞生的：引力使得由气体和尘埃构成的半透明状巨大云团发生收缩，最终点燃了恒星的核熔炉。但是象参宿四那样相对稀少的巨型恒星是如何出现的呢？同样多的物质材料通常可以产生一批象太阳大小的天体，甚至可以产生更多的普通红矮星。 |
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One possibility is that, like the largest galaxies and black holes, the biggest stars grow from collisions that happen early in their history. Alternatively, simulations have attributed the births of massive stars to the presence of turbulence, which churns up the parent cloud and keeps gravity from contracting the dust and gas into multiple births. But no one had seen this phenomenon in action until now. |
一种可能性是：跟最大型的星系和黑洞一样，最大型的恒星也产生于其早期历史上的碰撞。还有一种可能性：模拟显示巨型恒星的诞生是由于动荡状态造成的，这种动荡搅乱了母体云团，使引力无法将尘埃和气体收缩成多星诞生的状态。但是，此前没有人看到过这种实际的现象。 |
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In a bit of observational good fortune, a team from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, has spied the effects of turbulence directly using the Submillimeter Array, a cluster of telescopes on Mauna Kea in Hawaii that can track the internal dynamics of interstellar clouds with great precision. In one such cloud, about 15,000 light-years away, researchers led by astrophysicist Qizhou Zhang detected normal-sized stars emerging from relatively quiet regions, while a giant star was accumulating inside a zone of turbulence. They report the findings in a paper that has been accepted by The Astrophysical Journal. |
马萨诸塞州剑桥市哈佛-史密森天体物理中心的一个研究小组，在观察中凭借一丝好运直接发现了动荡状态带来的影响。他们利用了亚毫米波阵列望远镜，这是夏威夷莫纳基亚山上的一组望远镜，这些望远镜可以极其精确地跟踪观察星际间云团内部的动态。天体物理学家张其周（Qizhou Zhang的音译）带领的研究人员发现：在15,000光年以外的一个云团中，正常大小的恒星产生于相对平静的区域，而一颗巨型恒星正在一个动荡带内积聚起来。研究人员在一篇论文中报道了该发现，这篇论文已被《天体物理学杂志》接受。 |
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Theoretical astrophysicist Mark Krumholz of the University of California, Santa Cruz, says the new observations clearly reveal that turbulence prevents the formation of competing stars and allows a large one to keep growing. The challenge now is for theorists to explain the phenomenon in greater detail, he says. |
加州大学圣克鲁兹分校的理论天体物理学家马克·克鲁霍尔兹说，新的观察资料清晰地显示，动荡状态可以阻止群星互相竞争地形成，并促使巨型恒星不断地壮大起来。但是他表示，现在理论学家所面临的挑战是如何来更加详尽地解释这种现象。 |
