文章来源:未知 文章作者:meng 发布时间:2010-07-01 02:52 字体: [ ]  进入论坛

Many of the Milky1 Way's ancient stars are remnants(残留) of other smaller galaxies2 torn apart by violent galactic(银河的) collisions around five billion years ago, according to researchers at Durham University. Scientists at Durham's Institute for Computational Cosmology(宇宙学) and their collaborators at the Max Planck Institute for Astrophysics(天体物理学) , in Germany, and Groningen University, in Holland, ran huge computer simulations to recreate the beginnings of our galaxy3.

The simulations revealed that the ancient stars, found in a stellar halo(恒星晕) of debris4 surrounding the Milky Way, had been ripped from smaller galaxies by the gravity generated by colliding galaxies.

Cosmologists predict that the early Universe was full of small galaxies which led short and violent lives. These galaxies collided with each other leaving behind debris which eventually settled into more familiar looking galaxies like the Milky Way.

The researchers say their finding supports the theory that many of the Milky Way's ancient stars had once belonged to other galaxies instead of being the earliest stars born inside the galaxy when it began to form about 10 billion years ago.

The research, funded in the UK by the STFC, appears in the Monthly Notices of the Royal Astronomical5 Society.

Lead author Andrew Cooper, from Durham University's Institute for Computational Cosmology, said: "Effectively we became galactic archaeologists(考古学家) , hunting out the likely sites where ancient stars could be scattered6 around the galaxy.

"Our simulations show how different relics7(遗迹) in the galaxy today, like these ancient stars, are related to events in the distant past.

"Like ancient rock strata8(岩层) that reveal the history of Earth, the stellar halo preserves a record of a dramatic primeval(原始的,初期的) period in the life of the Milky Way which ended long before the Sun was born."

The computer simulations started from the Big Bang, around 13 billion years ago, and used the universal laws of physics to simulate the evolution of dark matter and the stars.

These simulations are the most realistic to date, capable of zooming9 into the very fine detail of the stellar halo structure, including star "streams" – which are stars being pulled from the smaller galaxies by the gravity of the dark matter.

One in one hundred stars in the Milky Way belong to the stellar halo, which is much larger than the galaxy's familiar spiral disk. These stars are almost as old as the Universe.

Professor Carlos Frenk, Director of Durham University's Institute for Computational Cosmology, said: "The simulations are a blueprint10 for galaxy formation.

"They show that vital clues to the early, violent history of the Milky Way lie on our galactic doorstep.

"Our data will help observers decode11 the trials and tribulations12(艰难困苦) of our galaxy in a similar way to how archaeologists work out how ancient Romans lived from the artefacts(人工制品) they left behind."

The research is part of the Aquarius Project, which uses the largest supercomputer simulations to study the formation of galaxies like the Milky Way.

Aquarius was carried out by the Virgo Consortium, involving scientists from the Max Planck Institute for Astrophysics in Germany, the Institute for Computational Cosmology at Durham University, UK, the University of Victoria in Canada, the University of Groningen in the Netherlands, Caltech in the USA and Trieste in Italy.

Durham's cosmologists will present their work to the public as part of the Royal Society's 350th anniversary 'See Further' exhibition, held at London's Southbank Centre until Sunday, July 4.

The highlight of their 'Cosmic Origins' exhibit is an award winning 3-D movie describing how the Milky Way formed. Visitors to the exhibit can also create their own star streams by colliding galaxies with an interactive13 3-D simulation.


1 milky JD0xg     
  • Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
  • I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。
2 galaxies fa8833b92b82bcb88ee3b3d7644caf77     
星系( galaxy的名词复数 ); 银河系; 一群(杰出或著名的人物)
  • Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
  • We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。
3 galaxy OhoxB     
  • The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
  • The company has a galaxy of talent.该公司拥有一批优秀的人才。
4 debris debris     
  • After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
  • Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
5 astronomical keTyO     
  • He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
  • Houses in the village are selling for astronomical prices.乡村的房价正在飙升。
6 scattered 7jgzKF     
  • Gathering up his scattered papers,he pushed them into his case.他把散乱的文件收拾起来,塞进文件夹里。
7 relics UkMzSr     
  • The area is a treasure house of archaeological relics. 这个地区是古文物遗迹的宝库。
  • Xi'an is an ancient city full of treasures and saintly relics. 西安是一个有很多宝藏和神圣的遗物的古老城市。
8 strata GUVzv     
  • The older strata gradually disintegrate.较老的岩层渐渐风化。
  • They represent all social strata.他们代表各个社会阶层。
9 zooming 2d7d75756aa4dd6b055c7703ff35c285     
adj.快速上升的v.(飞机、汽车等)急速移动( zoom的过去分词 );(价格、费用等)急升,猛涨
  • Zooming and panning are navigational tools for exploring 2D and 3D information. 缩放和平移是浏览二维和三维信息的导航工具。 来自About Face 3交互设计精髓
  • Panning and zooming, especially when paired together, create navigation difficulties for users. 对于用户来说,平移和缩放一起使用时,产生了更多的导航困难。 来自About Face 3交互设计精髓
10 blueprint 6Rky6     
  • All the machine parts on a blueprint must answer each other.设计图上所有的机器部件都应互相配合。
  • The documents contain a blueprint for a nuclear device.文件内附有一张核装置的设计蓝图。
11 decode WxYxg     
  • All he had to do was decode it and pass it over.他需要做的就是将它破译然后转给他人。
  • The secret documents were intercepted and decoded.机密文件遭截获并被破译。
12 tribulations 48036182395310e9f044772a7d26287d     
n.苦难( tribulation的名词复数 );艰难;苦难的缘由;痛苦
  • the tribulations of modern life 现代生活的苦恼
  • The film is about the trials and tribulations of adolescence. 这部电影讲述了青春期的麻烦和苦恼。 来自《简明英汉词典》
13 interactive KqZzFY     
  • The psychotherapy is carried out in small interactive groups.这种心理治疗是在互动的小组之间进行的。
  • This will make videogames more interactive than ever.这将使电子游戏的互动性更胜以往。
TAG标签: stars ancient galaxy