哪个行星的一天相当于地球一万年

哪个行星的一天相当于地球一万年
哪个行星的一天相当于地球一万年

哪个行星的一天相当于地球一万年
An astronomer picked up a mysterious pulse of light coming from the direction of the newly discovered Earth-like planet almost two years ago, it has emerged.
两年前,从刚刚被发现的一颗类地行星所在的方位上,一位天文学家曾接收到了一束神秘的光脉冲.
Dr Ragbir Bhathal, a scientist at the University of Western Sydney, picked up the odd signal in December 2008, long before it was announced that the star Gliese 581 has habitable planets in orbit around it.
西悉尼大学（University of Western Sydney）的科学家拉格比尔·巴瑟尔（Ragbir Bhathal）博士于2008年12月截获了这个奇怪的信号,当时地球上的人们还不知道这颗名为Gliese 581的恒星周围有一颗类似地球的宜居行星.
A member of the Australian chapter of SETI, the organisation that looks for communication from distant planets, Dr Bhathal had been sweeping the skies when he discovered a 'suspicious' signal from an area of the galaxy that holds the newly-discovered Gliese 581g.
作为SETI（这是一个寻求与遥远外星生命沟通的地球组织）澳大利亚分部的成员,巴瑟尔博士一直在对星空进行扫描,功夫不负有心人,他终于在某个星系的一片区域中找到了一个“可疑”信号,而新近发现的Gliese 581g行星正包含在这个星系中.
The remarkable coincidence adds another layer of mystery to the announcement last night that scientists had discovered another planet in the system: Gliese 581g - the most Earth-like planet ever found.
科学家刚刚宣布这颗名为Gliese 581g的行星是有史以来所发现的最类似地球的系外行星,一系列不同寻常的巧合为该天文发现裹上了一层神秘的面纱.
Dr Bhathal's discovery had come just months before astronomers announced that they had found a similar, slightly less habitable planet around the same star 20 light years away. This planet was called Gliese 581e.
当年,在巴瑟尔博士发现神秘信号几个月以后,天文学家就宣布在距离20光年处发现了一颗宜居程度稍低的行星,当时他们将这颗同位于Gliese 581恒星轨道上的行星命名为Gliese 581e.
When asked about his discovery at the time Dr Bhathal admitted he had been really excited about what he had possibly stumbled across.
巴瑟尔博士坦承,当时这个不经意间的发现让他感到十分兴奋.
He said: 'Whenever there’s a clear night, I go up to the observatory and do a run on some of the celestial objects. Looking at one of these objects, we found this signal.
他说：“不管什么时候,只要夜空晴朗,我就会登上天文台去搜索星体,在不经意间我们就发现了这个信号.
'And you know, I got really excited with it. So next I had to analyse it. We have special software to analyse these signals, because when you look at celestial objects through the equipment we have, you also pick up a lot of noise.'
“我当时相当激动,立刻着手对信号进行分析.我们有专门用来分析信号的软件,利用它可以去掉观测过程中带入的噪音.
He went on: 'We found this very sharp signal, sort of a laser lookalike thing which is the sort of thing we’re looking for - a very sharp spike. And that is what we found. So that was the excitement about the whole thing.'
“经过分析,我们找到了一个非常尖锐的信号,有点类似于激光,这就是我们一直在寻找的东西——一个非常尖锐的信号峰.我们如获至宝,激动万分.”
For months after his discovery Dr Bhathal scanned the skies for a second signal to see whether it was just a glitch in his instrumentation but his search came to nothing.
在接下来的几个月内,为了确保这不是因为仪器故障导致的假讯号,巴瑟尔博士又一次扫描了这片区域,但却一无所获.
Dr. Ragbir Bhathal received a signal from the direction of Gliese 581 - but has heard nothing since
格比尔·巴瑟尔博士曾在Gliese 581的方向上收到过神秘信号,但此后该信号却销声匿迹
But the discovery of Earth-like planets around Gliese 581 - both 581e and 581d, which was in the habitable zone - has also caught the public imagination.
但是Gliese 581e和Gliese 581d这两颗类地行星的发现勾起了公众无穷的想象力,它们都位于Gliese 581的轨道之上,而且处于宜居带中.
This artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star only 20 light years away from Earth. The four tiny planets in the background are the planets that have already been discovered. The closer, blue and green planet is 581G, the most Earth-like planet ever discovered
艺术家的概念图表现了Gliese 581系统中最靠内侧的四颗行星以及主恒星,主恒星是一颗距地球20光年的红矮星.背景上的四颗行星中,最靠近读者那颗蓝绿相间的行星即为581G,它是有史以来人类发现的最类似地球的行星
And Dr Steven Vogt who led the study at the University of California, Santa Cruz, today said that he was '100 per cent sure ' that there was life on the planet.
正在加州大学圣克鲁兹分校进行相关研究的史蒂夫·沃格特（Steven Vogt）博士今天表示说,他敢“100%肯定”这颗行星上有生命存在.
The planet lies in the star's 'Goldilocks zone' - the region in space where conditions are neither too hot or too cold for liquid water to form oceans, lakes and rivers.
这颗行星位于恒星的“适居带（Goldilocks zone）中”,所谓适居带指的是位于该区域的行星气候不会太冷也不会太热,有形成海洋、湖泊和河流的液态水.
The planet also appears to have an atmosphere, a gravity like our own and could well be capable of life. Researchers say the findings suggest the universe is teeming with world like our own.
Gliese 581g上似乎也存在大气,引力类似于地球,非常适合于生命形成.研究者认为这些发现表明,宇宙中可能存在很多类似于地球的星体.
'If these are rare, we shouldn't have found one so quickly and so nearby,'
沃格特博士在接受探索新闻（Discovery News）时表示说：“如果这样的行星很稀少的话,我们不会这么快就找到一颗,而且还是在如此近的距离上,”
'The number of systems with potentially habitable planets is probably on the order of 10 or 20 per cent, and when you multiply that by the hundreds of billions of stars in the Milky Way, that's a large number. There could be tens of billions of these systems in our galaxy.'
“拥有宜居行星的行星系统数量可能占总数的10%或20%,考虑到光是银河系中就有数以亿计的行星系统,乘以这个数字,你会得出一个极其巨大的数目,因此银河系中可能存在上亿颗类地行星.”
He told Discovery News: 'Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say that the chances for life on this planet are 100 percent. I have almost no doubt about it'.
“个人认为,鉴于生命的普遍性和在适宜环境中繁盛的倾向性,我敢说这颗行星上存在生命的可能性是 100%,对此,我几乎不抱怀疑态度.”
The planet is so far away, spaceships travelling close to the speed of light would take 20 years to make the journey. If a rocket was one day able to travel at a tenth of the speed of light, it would take 200 years to make the journey.
这颗行星过于遥远,以接近光速飞行的宇宙飞船都要花费20年时间才能抵达.如果有朝一日,人类能乘坐以十分之一光速飞行的火箭进行星际旅行,抵达Gliese 581g需要花费200年.
Planets orbiting distant stars are too small to be seen by telescopes. Instead, astronomers look for tell-tale gravitational wobbles in the stars that show a planet is in orbit.
位于遥远星系的行星过于渺小,无法用望远镜进行直接观测,因此天文学家通过恒星指示性的引力摆动（gravitational wobbles）来寻找其周围轨道上的行星.
The findings come from 11 years of observations at the W. M. Keck Observatory in Hawaii.
位于夏威夷的W·M·凯克天文台（W. M. Keck Observatory）在进行了11年的观测以后,终于发现了这颗行星.
The planet orbits a small red star called Gliese 581 in the constellation of Libra. The planet, named Glieseg, is 118,000,000,000,000 miles away - so far away that light from its start takes 20 years to reach the Earth.
围绕Gliese 581公转的这颗类地行星位于天秤座（constellation of Libra）,距离地球非常遥远,Gliese 581的恒星光芒需要旅行20年才能抵达地球.
It takes just 37 days to orbit its sun which means its seasons last for just a few days. One side of the planet always faces its star and basks in perpetual daylight, while the other is in perpetual darkness.
该行星的公转周期为37天,这意味着它上面的四季变换非常迅速.它有一面一直是面向红矮星,因此处于永恒的白昼,而另一面则处于极夜状态.
The most suitable place for life or future human colonists would be in the 'grey' zone - the band between darkness and light that circles the planet.
最适合生命存在或未来人类殖民的区域是行星上的那些“灰色”地带——即位于极昼和极夜之间那些环绕行星的区域.
'Any emerging life forms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude,' said Dr Vogt who reports the find in the Astrophysical Journal.
“所有潜在的生命形式都会选择大范围的适宜天气进行生存和进化,以这颗行星来说,这取决于经度,”沃格特博士在《天体物理学报》（Astrophysical Journal）的论文中这样写到.
If Gliese 581g has a rocky composition similar to the Earth's, its diameter would be about 1.2 to 1.4 times that of the Earth. It's gravity is likely to be similar - allowing a human astronaut to walk on the surface upright without difficulty.
如果Gliese 581g与地球类似也是由岩石构成,那么它的直径约为地球的1.2至1.4倍,而且引力也大致相同——可以让人类宇航员在其地表上不费力的直立行走.
'This planet doesn't have days and nights. Wherever you are on this planet, the sun is in the same position all the time. You have very stable zones where the ecosystem stays the same temperature... basically forever,' Vogt said.
“这颗行星没有白昼和黑夜之分.不管你身处何处,太阳总是处于同一位置.在一个非常稳定的区域中,生态系统保持恒温.基本是永恒的状态,”沃格特说.
Gliese 581, the brightest object in this Nasa image from 2007, is only 20 light years from Earth and is one of our nearest neighbours
这张照片是NASA2007年拍摄的,其中最明亮的星体便是Gliese 581,它距地球20光年,是太阳系最近的邻居之一
'If life can evolve, it's going to have billions and billions of years to adapt to the surface. Given the ubiquity of water, it seems probable that this thing actually has liquid water. On the surface of the Earth, everywhere you have liquid water you have life,' Vogt added.
“如果Gliese 581g上的生命也能进化,它肯定是花费了数亿年的时间来适应行星表面.水是无处不在的,似乎这颗行星上就存在液态水.而在地球表面上,只要有液态水,就会有生命存在,”沃格特又补充说.
Astronomers have now found six planets in orbit around Gliese 581 - the most discovered in a planetary system other than our own solar system.
天文学家在Gliese 581周围已经发现了六颗行星——除了我们的太阳系之外,Gliese 581是人类发现行星最多的行星系.
Like the solar system, the planets orbiting Gliese 581 have mostly circular orbits.
和太阳系一样,围绕着Gliese 581运行的行星轨道大部分都是圆形的.
Two of its detected planets have previously been proposed as habitable planets. However they lie at the extremes of the Goldilocks Zone - one on the hot side, the other on the cold side.
先前发现的两颗行星被认为处于适居带中,但现在看来它们位于这一区域的边缘——一个过热,一个太冷.
Gliese 581g, in contrast, lies right in the middle.
相比之下,Gliese 581g正好位于这一区域的中间.
The star has not been given a proper name. It appears in a catalogue of stars compiled by the German astronomer William Gliese where it has been given the reference number 581.
红矮星Gliese 581没有被正式命名,它出现在德国天文学家威廉·葛利斯（William Gliese ）编纂的恒星目录中,参考号为581.
Astronomers name planets found orbiting stars with a letter.
天文学家通过添加一个字母来为其周围的行星命名.
The previous five planets found around Gliese 581 were named b to f, making the latest discovery Gliese 581g.
早先在Gliese 581周围发现的五颗行星以b到f来命名,最新的一颗则被命名为Gliese 581g.
Its star is a red giant - a massive star near the end of its life. It is too dim to see in the night sky from Earth without a telescope.
Gliese 581是一颗已经接近生命终点的红巨星,星光十分暗淡,在没有天文望远镜的情况下,从夜空中根本无法看到.
Astronomers have found nearly 500 exoplanets - or planets outside our own solar system.
天文学家已经发现了将近500颗太阳系以外的地外行星.
However, almost all are too big, made of gas instead of rock, too hot or too cold for life as we know it.
但是,大多数都是巨大的气态行星,过热或过冷,我们已知的生命在上面根本无法生存.
The orbits of planets in the Gliese 581 system are compared to those of our own solar system. The Gliese 581 star has about 30% the mass of our sun, and the outermost planet is closer to its star than we are to the sun. The 4th planet, G, is a planet that could sustain life.
Gliese 581系统的行星轨道与太阳系的比较图.红矮星Gliese 581只有太阳质量的30%,比起太阳系的外层行星,该系统最外层的行星距离红矮星要更近.有可能维持生命存在的Gliese 581g为第四颗行星.
Gliese 581g档案：
直径：地球的1.2至1.4倍
质量：地球的3.1至4.3倍
表面平均温度：华氏零下24度至10度（摄氏零下31度至零下12度）
距离地球：20光年（或118,000,000,000,000英哩）
旅行所需时间：搭十分之一光速的火箭前往,（或每秒速度 19,000 英哩,约需200年）是六颗环绕着Gliese 581红矮星运行的行星之一.
一年的天数：约地球的37天
重力：约莫相等或略高于地球
跟太阳（红矮星）的距离：约600万英哩.Gliese 581红矮星约等于我们的太阳的三分之一大.比太阳“凉快”50倍 .
构成：岩石、液体水与大气

太阳系可真没有这样子的行星。自转慢有两种原因：1轨道原因自转方向和公转方向相反（金星）或旋转轴与公转轨道夹角过小；2星体离中心天体近，守中心天体影响自转慢。但是在太阳系没有这样子的行星。

太阳系里没有， 别的恒星除非很大，要不然这么慢的自转行星早就飞离母星了