||1: It joins two other Earthlike planets-Gliese 581d and HD 85512 b-discovered by another instrument within the past few years. ||2: In truth, the term “Earthlike ” is a stretch. Kepler 22b has a radius 2.4 times that of Earth, and if it is made from roughly the same stuff its surface gravity will also be about 2.4 times as strong. ||3: But NASA’s astronomers remain unsure whether it is predominantly gaseous, liquid or solid.

||1: 它加入了另外两个类地球行星——Gliese 581d 和HD 85512 b—在过去的几年里被另外的仪器发现的。 ||2: 事实上，“类地球行星”这个词言过其实，Kepler 22b半径是地球的2.4倍，如果它和地球的组成大致相同，它的表面引力也将大约高达地球引力的2.4倍。 ||3:但是美国国家航天与宇宙航行局的天文学家仍不能确定它主要是气体的、液体的或是固体的。

||1:When Dr Koechlin and his team pointed it at Mars they could distinguish that planet’s two tiny moons-a task which would require a Newtonian telescope with a mirror at least 30cm across.||2:And when they aimed at Sirius they could see the dim white-dwarf which orbits what is the brightest star in the night sky.||3:Extrapolating from these results, they think that an orbiting zone plate measuring somewhere between 15 metres and 40 metres across will be enough to distinguish the spectrum of an Earthlike planet at a distance of 30 light-years.||4:With that, they should be able to find out if mankind really does have any next-door neighbours, and Fresnel will have come into his own at last.

||1:当凯什兰博士和他的团队观测火星时，他们可以分辨火星的两个微小卫星——这样的任务如果是利用牛顿的望远镜则需要一个直径最少长达30厘米的镜面。||2:并且，当他们观测天王星时，他们能够看见暗淡的白矮星。它围绕着夜空中最亮的那颗星运行。||3:从这些结果推测，他们认为，一个直径在15到40米、并且在轨道上运行的波带片足够在30光年以外的距离分辨一个与地球相似的行星的光谱。||4:如此一来，他们就应该能够找到人类是否还有其他邻居，而菲涅尔也最终能实现自己的想法。

||1:The ultimate goal, of course, is to let astronomers make a plausible estimate of the total number of planets in the galaxy, of the number that could conceivably support life, and of the fraction of those that could (at least in theory) sustain human colonists.||2:If only a few of Kepler’s possible Earthlike planets turn out to be real, that third number is likely to be in the millions.

||1:当然最终的目标是让天文学家对银河系的行星总数、确定可以维持生命的行星数和那些可以维持人类殖民者生命（至少在理论上）的行星比例做出一个接近可信的估算。||2:如果Kepler类地行星中只有很少被证明是真的，第三个数可能是数百万。

||1: ONE of the more memorable slogans to come out of the climate-change talks in Durban over the past few days is: “there is no planet B”. But what if there were? ||2: Over the past couple of decades astronomers have logged thousands of so-called “exoplanets”—worlds which orbit stars other than the sun. ||3: On December 5th the scientists in charge of Kepler, a space telescope designed to look for such planets, confirmed their instrument’s discovery of its first Earthlike world.

||1:在过去几天的Durban气候变化会谈上提出的较难忘的口号之一就是“没有星球B”，但是如果有呢？||2:在过去的几十年内，天文学家记载了数以千计的所谓的“外行星”---饶太阳以外的星球轨道运行的宇宙。||3:12月5号，负责开普勒号的科学家确认他们的仪器发现了第一个类地球星体，开普勒号是专门为寻找这样的类地球星体而设计的太空望远镜。

The existence of the most Earthlike planet yet has just been confirmed

类地球行星的存在已刚被确认

But it was the asteroid’s earthlike orbit that really got the astronomers’ attention.

不过真正让天文学家感兴趣的是它的类地球轨道。

For a planet to be truly Earthlike , how long it has been around might be one of its most important features.

对于一个真正的类地行星来说，其星龄也许是其大多数重要特性中的一点。

If it does, that would have important implications for Kepler’s main mission, which is to search for Earthlike planets.

如果是，那么对于“开普勒”望远镜搜寻类地型行星这个主要任务来说将有着重要的牵连意义。

We would have two striking similarities to our solar system: a Jupiterlike planet and an Earthlike planet.

我们会发现它与太阳系有着两大惊人的相似之处，那就是与木星相似的行星和与地球相似的行星。