关于宇宙的英语短文
发布网友
发布时间：2022-05-20 17:08
共5个回答
热心网友
时间：2023-10-09 00:16
What reason is there to think that we may actually detect intelligent life in outer space? To begin with, modern theories of the development of stars suggest that almost every star has some sort of family of planets. So any star like our wan sun (and there are billions of such stars in the universe) is likely to have a planet situated at such a distance that it would receive about the same amount of radiation as the earth.
Furthermore, such a planet would probably have the same general composition as our own; so, allowing a billion years or two — or three — there would be a very good chance for life to develop, if current theories of the origin of life are correct.
But intelligent life? Life that has reached the stage of being able to sent radio waves out into space in a deliberate pattern? Our own planet may have been in existence for five billion years and may have had life on it for two billion, but it is only in the last fifty years that intelligent life capable of sending radio waves into space has lived on earth. From this it might seem that even if there were no technical problems involved, the chance of receiving signals from any particular earth-type planet would be extremely small.
This does not mean that intelligent life at our level does not exist somewhere. There is such an unimaginable number of stars that, even at such miserable odds, it seems certain that there are million of intelligent life forms scattered through space. The only trouble is, none may be within hailing distance of us. Perhaps none ever will be; perhaps the appalling distances that separate us from our fellow denizens of this universe will forever remain too great to be conquered. And yet it is conceivable that someday we may come across one of them or, frighteningly, one of them may come across us. What would they be like, these extraterrestrial creatures?
2 Tiny Tonga Launches Space Tourism Plan
The tiny poverty-stricken South Pacific state f Tonga has always had serious problems raising money, and so it has always been entrepreneurial. It his sold Tongan passports to Hong Kong businessmen; it sold possible satellite broadcasting locations in space; it even officially changed to a different time zone to be the first country to welcome the new millennium.1
Now Tonga’s latest money-making venture is a plan to become the world center of space tourism. The Tonga government has made an agreement with a US company to allow it to use on of its 170 islands to launch rockets that will take tourists on week-long trips into space at a cost of US$2 million each.2
For this price, space tourists receive 60 days’ training in a “resort setting”, followed by the holiday of a lifetime orbiting the Earth.3 Two astronaut pilots and four astronaut tourists will make the trip. However, skeptics say that these budgets are inadequate. Although they predict that space tourism will eventually bring an income of US$10-20 billion a year, they calculate that the budget of $8 million per trip will not be enough to pay for the required technology.
Comparison with the current space tourism programme suggests this maths may be accurate. To ride the Russian Soyuz (the only tourist ride currently available) costs more than US$20 million per person. However, other people, including one important ex-cosmonaut4, criticize the Russian government for raising money in this way, even though it uses the money for the space quota of space missions without achieving anything. He also believes that these inexperienced tourists would e a danger in a difficult or life-threatening crisis in space.5
3 Astronomy (天文学) is the oldest science known to man.Thousands of years ago man looked at the stars and wondered about the heavens.But man was limited (*) by six planets that he could see with his eyes alone.
The Greeks (希腊人) studied astronomy over 2,000 years ago.They could see the size, color, and brightness of a star.They could see its place in the sky.They watched the stars move as the seasons changed.But the Greeks had no tools to help themselves study the heavens.
Each new tool added to the field of astronomy helped man reach out into space. Until there were telescopes (望远镜), man knew a little about the moon.He did not know that the planet called Saturn (土星) had rings around it.His sight was so limited that he could not see all the planets.In the early 1700s, people thought there were only six planets.Pluto (冥王星), the last of nine planets to be discovered, was not seen until 1930.
Before the spectroscope (分光镜), man did not know what kind of gases was in the sun or other stars.Without the radiotelescope (射电望远镜), we did not know that radio noises came from far in space.
Today, astronomy is a growing science.We have learned more in the last fifty years than in the whole history of astronomy.
热心网友
时间：2023-10-09 00:16
"宇宙是有限的还是无限的？有没有中心有没有边？有没有生老病死有没有年龄？"这些恐怕是自从有人类的活动以来一直被关心的问题。为了有一个更清楚的答案，让我们先来看看它的组成和结构吧。宇宙中的天体绚丽多彩，表现出了极高的层次性。
(1) 行星
我们居住的地球是太阳系的一颗大行星。太阳系一共有九颗大行星：水星、金星、地球、火星、木星、土星、天王星、海王星、冥王星。除了大行星以外，还有60多颗卫星、为数众多的小行星、难以计数的彗星和流星体等。他们都是离我们地球较近的，是人们了解的较多的天体。那么，除了这些以外，茫茫宇宙空间还有一些什么呢？
(2) 恒星和星云
晴夜，我们用肉眼可以看到许多闪闪发光的星星，他们绝大多数是恒星，恒星就是象太阳一样本身能发光发热的星球。我们银河系内就有1000多亿颗恒星。恒星常常爱好"群居"，有许多是"成双成对"地紧密靠在一起的，按照一定的规律互相绕转着，这称为双星。还有一些是3颗、4颗或更多颗恒星聚在一起，称为聚星。如果是十颗以上，甚至成千上万颗星聚在一起，形成一团星，这就是星团。银河系里就发现1000多个这样的星团。
在恒星世界中还有一些亮度会发生变化的星-变星。它们有的变化很有规律，有的没有什么规律。现在已发现了2万多颗变星。有时侯天空中会突然出现一颗很亮的星，在两三天内会突然变亮几万倍甚至几百万倍，我们称它们为新星。还有一种亮度增加得更厉害的恒星，会突然变亮几千万倍甚至几亿倍，这就是超新星。
除了恒星之外，还有一种云雾似的天体，称为星云。星云由极其稀薄的气体和尘埃组成，形状很不规则，如有名的猎户座星云。
在没有恒星又没有星云的广阔的星际空间里，还有些什么呢？是绝对的真空吗？当然不是。那里充满着非常稀薄的星际气体、星际尘埃、宇宙线和极其微弱的星际磁场。随着科学技术的发展，人们必定可以发现越来越多的新天体。
(3) 银河系及河外星系
随着测距能力的逐步提高，人们逐渐在越来越大的尺度上对宇宙的结构建立了立体的观念。这里第一个重要的发展，是认识了银河。它包含两重含义，一是了解了银河的形状，二是认识了河外天体的存在。
银河系是太阳所属的一个庞大的恒星集团，约包括1011颗恒星。这种恒星集团叫星系。银河系中大部分恒星分布成扁平的盘状。盘的直径为25kpc（千秒差距，1秒差距＝3.26光年＝3.09亿亿米），厚度约为2kpc。盘的中心有一球状隆起，称为核球。盘的外部由几条旋臂构成。太阳位于其中一条旋臂上，距离银心约7kpc。银盘上下有球状的延展区，其中恒星分布较稀疏，称为银晕。晕的总质量约占整体的10%，直径约为30kpc。我们的太阳，就其光度，质量和位置讲，都只是银河系中一个极普通的成员。
此外重要的是，并非天穹上一切发光体都是银河系的一部分。设想有一个类似银河系的恒星集团，处于500kpc的距离上（银河自身大小为30kpc）。其表观亮度与2pc远处一颗类似太阳的恒星是一样的。因此对天穹上的某个光点，只有测定它的距离，才能区分它是银河系内的恒星还是银河系外的另一个星系。实际上，天穹上的大多数光点是银河系的恒星，但也有相当大量的发光体是与银河系类似的巨大恒星集团，历史上曾被误认为是星云，我们称它们为河外星系，现在已知道存在1000亿个以上的星系，著名的仙女星系、大小麦哲伦星云就是肉眼可见的河外星系。星系的普遍存在，表明它代表宇宙结构中的一个层次，从宇宙演化的角度看，它是比恒星更基本的层次。
星系的质量差别很大。银河系的质量约为1011M⊙(太阳质量单位)。在明亮的星系中，这是典型的大小。质量很小的星系太暗，不易看到。小星系的质量可低达106M⊙。星系的典型尺度为几十千秒差距。若对视星等在23等以内的星系作统计，星系总数在109以上。
20世纪60年代以来，天文学家还找到一种在银河系以外象恒星一样表现为一个光点的天体，但实际上它的光度和质量又和星系一样，我们叫它类星体，现在已发现了数千个这种天体。
(4) 星系团
当我们把观测的尺度再放大，宇宙可看成由大量星系构成的"介质"，而恒星只是星系内部细致结构的表现。这样，为了了解宇宙结构，需关心星系在空间的分布规律。
星系的空间分布不是无规的，它也有成团现象。上千个以上的星系构成的大集团叫星系团。大约只有10%星系属于这种大星系团。大部分星系只结成十几、几十或上百个成员的小团。可以肯定的是，星系团代表了宇宙结构中比星系更大的一个新层次。这层次的尺度大小为百万秒差距，平均质量是星系平均质量的100倍。
(5) 大尺度结构
今天人们把10Mpc以上的结构称为宇宙的大尺度结构（目前观测到的宇宙的大小是104Mpc）。至今大尺度上的观测事实远不是十分明确的。有趣的是，有迹象表明，星系在大尺度上的分布呈泡沫状。即有许多看不到星系的"空洞"区，而星系聚集在空洞的壁上，呈纤维状或片状结构。这一层次的结构叫超星系团。它的典型尺度为几十兆秒差距。
从演化理论来考虑，尺度大到一定程度，应不再有结构存在。这是否符合事实，以及这尺度多大，都是十分重要，并需要有大尺度观测来回答的问题。现今对宇宙在50Mpc以上是否还有显著的结构现象存在，正是人们热烈争论中的焦点。
总之，若把星系看成宇宙物质的基本单元，那么星系的分布状况就是宇宙结构的表现。现在看来，直至50Mpc的尺度为止，星系的分布呈现有层次的结构。这就是我们对宇宙面貌的基本认识。
请高手翻译成英文吧
参考资料：我不是外国人,我不懂英文
热心网友
时间：2023-10-09 00:17
What reason is there to think that we may actually detect intelligent life in outer space? To begin with, modern theories of the development of stars suggest that almost every star has some sort of family of planets. So any star like our wan sun (and there are billions of such stars in the universe) is likely to have a planet situated at such a distance that it would receive about the same amount of radiation as the earth.
Furthermore, such a planet would probably have the same general composition as our own; so, allowing a billion years or two — or three — there would be a very good chance for life to develop, if current theories of the origin of life are correct.
But intelligent life? Life that has reached the stage of being able to sent radio waves out into space in a deliberate pattern? Our own planet may have been in existence for five billion years and may have had life on it for two billion, but it is only in the last fifty years that intelligent life capable of sending radio waves into space has lived on earth. From this it might seem that even if there were no technical problems involved, the chance of receiving signals from any particular earth-type planet would be extremely small.
This does not mean that intelligent life at our level does not exist somewhere. There is such an unimaginable number of stars that, even at such miserable odds, it seems certain that there are million of intelligent life forms scattered through space. The only trouble is, none may be within hailing distance of us. Perhaps none ever will be; perhaps the appalling distances that separate us from our fellow denizens of this universe will forever remain too great to be conquered. And yet it is conceivable that someday we may come across one of them or, frighteningly, one of them may come across us. What would they be like, these extraterrestrial creatures?
2 Tiny Tonga Launches Space Tourism Plan
The tiny poverty-stricken South Pacific state f Tonga has always had serious problems raising money, and so it has always been entrepreneurial. It his sold Tongan passports to Hong Kong businessmen; it sold possible satellite broadcasting locations in space; it even officially changed to a different time zone to be the first country to welcome the new millennium.1
Now Tonga’s latest money-making venture is a plan to become the world center of space tourism. The Tonga government has made an agreement with a US company to allow it to use on of its 170 islands to launch rockets that will take tourists on week-long trips into space at a cost of US$2 million each.2
For this price, space tourists receive 60 days’ training in a “resort setting”, followed by the holiday of a lifetime orbiting the Earth.3 Two astronaut pilots and four astronaut tourists will make the trip. However, skeptics say that these budgets are inadequate. Although they predict that space tourism will eventually bring an income of US$10-20 billion a year, they calculate that the budget of $8 million per trip will not be enough to pay for the required technology.
Comparison with the current space tourism programme suggests this maths may be accurate. To ride the Russian Soyuz (the only tourist ride currently available) costs more than US$20 million per person. However, other people, including one important ex-cosmonaut4, criticize the Russian government for raising money in this way, even though it uses the money for the space quota of space missions without achieving anything. He also believes that these inexperienced tourists would e a danger in a difficult or life-threatening crisis in space.5
3 Astronomy (天文学) is the oldest science known to man.Thousands of years ago man looked at the stars and wondered about the heavens.But man was limited (*) by six planets that he could see with his eyes alone.
The Greeks (希腊人) studied astronomy over 2,000 years ago.They could see the size, color, and brightness of a star.They could see its place in the sky.They watched the stars move as the seasons changed.But the Greeks had no tools to help themselves study the heavens.
Each new tool added to the field of astronomy helped man reach out into space. Until there were telescopes (望远镜), man knew a little about the moon.He did not know that the planet called Saturn (土星) had rings around it.His sight was so limited that he could not see all the planets.In the early 1700s, people thought there were only six planets.Pluto (冥王星), the last of nine planets to be discovered, was not seen until 1930.
Before the spectroscope (分光镜), man did not know what kind of gases was in the sun or other stars.Without the radiotelescope (射电望远镜), we did not know that radio noises came from far in space.
Today, astronomy is a growing science.We have learned more in the last fifty years than in the whole history of astronomy.
热心网友
时间：2023-10-09 00:17
I'm very happy when I heard the news that China's first manned spacecraft,Shenzhou 5,was launched on October 15,2003. I would never forget the day when all the Chinese people were proud of the successful launch.
The first unmanned "Shenzhou 1"space craft and "Shenzhou 5" spacecraft, showed China's space science and technology has reached a very high level. The launch of the "Shenzhou 5" is a great feat. The dreams of thousands of astronauts have come true.
I'm a high school student now. Yang Liwei has set a good example for us all. I want to study hard and lay solid foundations for my future. When I grow up, I want to become an astronaut like Yang Liwei.
热心网友
时间：2023-10-09 00:18
