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The Largest Structure in
the Universe
| Astronomers
have discovered the largest
structure yet seen in the universe, a clump
of quasars so large that it would take light 4 billion years to
traverse its widest dimension. Light from these quasars started its
journey when the universe was only 5 billion years old, the
researchers say. Far larger than previously discovered groups of
quasars, the structure (artist's depiction of a single quasar) is
so large that it challenges Albert Einstein's cosmological
principle—the notion that the universe, at large scales, looks the
same no matter the direction and locale from which you look.
According to that theory, the researchers say, the universe's
large-scale structures—in this case, clumps of objects such as
quasars—shouldn't be larger than 1.2 billion light-years across.
The elongated, newly discovered large quasar group (LQG) is, on
average, about 1.63 billion light-years across but in its largest
dimension is more than 4 billion light-years across, the
researchers report today in Monthly
Notices of the Royal Astronomical Society. By comparison,
typical clusters of galaxies can be nearly 10 million light-years
across. Bringing the comparison to our cosmic neighborhood, the new
record-holding group of quasars spans about 1600 times the distance
between our Milky Way galaxy and our neighbor
Andromeda. |
天文学家们发现了宇宙中可以看到的最大结构——一个类星体团，该类星体团如此巨大，要想穿越其最宽阔的部分，光也需要利用40亿年的时间。研究人员称，当宇宙只有50亿岁的时候，这些类星体的光线就开始了其行程。该结构比以前发现的类星体团都要大得多（见图中艺术家描绘的一个类星体），以至于对爱因斯坦的宇宙论原则构成了挑战。爱因斯坦的观点为：从大尺度上来讲，不管一个人从哪个方向，也不论从什么位置去观看，宇宙看起来总是相同的。研究人员说，根据这一理论，宇宙中大尺度结构（如该情况中的类星体团）的跨度不应该超过12亿光年。今天，研究人员在《皇家天文学会月刊》上报道说：这个新发现的狭长状大型类星体团（LQG）平均跨度大约为16.3亿光年，最宽阔处超过40亿光年。相比之下，典型的星系团只有将近1000万光年的跨度。再到我们宇宙近邻来做一下比较：这个打破新记录的类星体团的跨度，大约相当于我们银河系跟邻居仙女座星系之间距离的1600倍。 |
译自：美国《科学》杂志网站（11
January 2013, 2:20 PM）
原著：Sid
Perkins![]()
青春就应该这样绽放 游戏测试：三国时期谁是你最好的兄弟！！ 你不得不信的星座秘密![]()
青春就应该这样绽放 游戏测试：三国时期谁是你最好的兄弟！！ 你不得不信的星座秘密