本帖最后由 gohomeman1 于 2010-7-4 21:25 编辑
“Matter is not distributed uniformly in the Universe,” says Masayuki Tanaka from ESO, who led the new study. “In our cosmic vicinity, stars form in galaxies and galaxies usually form groups and clusters of galaxies. The most widely accepted cosmological theories predict that matter also clumps on a larger scale in the so-called ‘cosmic web’, in which galaxies, embedded in filaments stretching between voids, create a gigantic wispy structure.”
田中雅行，新研究报告首席研究员在ESO说：“宇宙中的物质不是均匀分布的。在我们附近的宇宙，恒星组成了星系，而星系常常成群成团。最广泛流行的宇宙论预测物质将组成更高一级的结构——宇宙之网，它们是在空间延伸的纤维状结构，星系则嵌入其中。”
These filaments are millions of light years long and constitute the skeleton of the Universe: galaxies gather around them, and immense galaxy clusters form at their intersections, lurking like giant spiders waiting for more matter to digest. Scientists are struggling to determine how they swirl into existence. Although massive filamentary structures have been often observed at relatively small distances from us, solid proof of their existence in the more distant Universe has been lacking until now.
这些纤维状结构横亘数百万光年，构成了宇宙的骨架：星系聚集在其周围，在其交汇处则形成巨大的星系团，就像巨大的蜘蛛等着消化更多的物质。科学家正在努力研究，了解这些物质为何纠集于此。虽然在相对较小的距离内，我们常常观测到这类大质量丝缕结构，但在本报告之前，如此大距离上的确凿证据却一直缺乏。
The team led by Tanaka discovered a large structure around a distant cluster of galaxies in images they obtained earlier. They have now used two major ground-based telescopes to study this structure in greater detail, measuring the distances from Earth of over 150 galaxies, and,hence, obtaining a three-dimensional view of the structure. The spectroscopic observations were performed using the VIMOS instrument on ESO’s Very Large Telescope and FOCAS on the Subaru Telescope, operated by the National Astronomical Observatory of Japan.
田中雅行领导的团队在他们早先观测的一个遥远星系团附近，发现了这个大型结构。他们主要使2个大型地面望远镜详细研究此结构，测量了150多个星系距离，并由此获得整个结构的三维视图。执行光谱分析的仪器是ESO甚大望远镜（VLT）的可见光多目标光谱仪（VIMOS）和隶属于日本国家天文台（NAOJ）的斯巴鲁望远镜的微光天体分光仪（FOCAS）。
Thanks to these and other observations, the astronomers were able to make a real demographic study of this structure, and have identified several groups of galaxies surrounding the main galaxy cluster. They could distinguish tens of such clumps, each typically ten times as massive as our own Milky Way galaxy — and some as much as a thousand times more massive — while they estimate that the mass of the cluster amounts to at least ten thousand times the mass of the Milky Way. Some of the clumps are feeling the fatal gravitational pull of the cluster,and will eventually fall into it.
感谢这些高级分析仪器，天文学家对此结构进行了详实的统计分析，并鉴别出围绕主星系团的数个星系群。他们辨别出10个群，每群质量至少10倍于银河系，其中某些甚至大千倍，整体质量估计万倍于我们银河系。其中的某些群受主星系团强大的毁灭性引力牵扯，最终将落入主星系团中。
“This is the first time that we have observed such a rich and prominent structure in the distant Universe,” says Tanaka. “We can now move from demography to sociology and study how the properties of galaxies depend on their environment, at a time when the Universe was only two thirds of its present age.”
田中说：“这是我们首次在遥远宇宙观测到如此丰富而显著的丝缕结构。根据观测统计，我们现在能够把不属于结构的星系群分离，并研究在宇宙当前年龄2/3的时代，星系与其环境间相互关系的特性。”
The filament is located about 6.7 billion light-years away from us and extends over at least 60 million light-years. The newly uncovered structure does probably extend further, beyond the field probed by the team, and hence future observations have already been planned to obtain a definite measure of its size.
这个丝缕结构离我们约67亿光年，占据了约6000万光年的空间。新的未发现的结构也许延伸得更远，超过团队调研的天区。因此，进一步的观测和测定它的大小已经规划进行。
附图为PDF文件中的插图——gohomeman1注 |
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