外星移民不是夢 超級地球被確認存在
Astronomers believe mysterious signals - previously dismissed as stellar bursts - are coming from an Earth-like planet.
早前被認爲是由附近星體出現磁場爆炸造成的光的Gliese 581d近日被天文學家確認存在。
The Gliese 581d planet has conditions that could support life, and is likely to be a rocky world, twice the size of Earth.
Gliese 581d行星有着適合人類居住的環境，可能和地球一樣存在岩石，體積是地球的兩倍。
Signals from the planet were initially discovered in 2010, but last year dismissed as noise from distant stars.
2010年天文學家第一次發現來自Gliese 581d的信號，但是去年這些信號又被科學家認爲是其他遙遠星球發出的噪音。
Now, a further study claims that the 2014 research was based on 'inadequate analyses of the data' and that Gliese 581d does exist.
而最新研究表明，2014年的數據分析方法不適當，所以Gliese 581d行星可能確實存在。
Last year, Pennsylvania State University researchers said Gliese 581d - and its companion Gliese 581g - were simply a trick of the light caused by magnetic bursts from a local star 22 light-years away.
去年，美國賓夕法尼亞州州立大學的研究人員曾指出Gliese 581d和581g發出的信號不過是距離地球約22光年的一顆星體出現磁場爆發繼而造成的光把戲。
The new British research, however, argues the method used by the Pennsylvania team was only suitable for large planets, and that it could miss small ones like GJ 581d.
但是來自英國的最新研究稱，賓州大學研究團隊之前使用的研究方法只適合較大行星，所以可能會漏掉如GJ 581d這樣的小行星。
The study, by Queen Mary University, London and the University of Hertfordshire, claims to use a more accurate model on the existing data.
英國倫敦大學瑪麗皇后學院與赫特福德郡大學聯合進行的這項研究稱對現有數據使用了更加準確的分析模型。
'The existence (or not) of GJ 581d is significant because it was the first Earth-like planet discovered in the 'Goldilocks'-zone around another star ,' said lead author, Dr Guillem Anglada-Escudé.
該研究的負責人古伊勒姆·安格拉達·埃斯庫德博士說：“GJ 581d是否存在意義重大，因爲它是在宜居帶內發現的第一顆繞其他恆星運轉的類地行星。”
'There are always discussions among scientists about the ways we interpret data but I'm confident that GJ 581d has been in orbit around Gliese 581 all along.
“在我們解釋數據使用的方法上科學家們一直存在爭議，但我相信GJ 581d一直都在繞着Gliese 581的軌道上運行的。”
GJ 581d is believed to be the first planet outside our solar system in the Goldilocks zone around its star – an area not too hot and not too cold for life.
GJ 581d被認爲是在太陽系之外宜居帶內發現的繞恆星運動的第一顆行星。宜居帶不冷不熱，適合生命生存。
To find Gliese 581d, University of California, Santa Cruz astronomers originally looked for subtle changes in light caused by the gravity of an orbiting planet tugging back and forth on the star.
爲尋找Gliese 581d，加利福尼亞大學的聖克魯斯天文學家們最初發現了由繞恆星運行的行星來回擺動造成的光變化。
The strength of the tugging, they believed, showed them a planet was about three times as massive as Earth.
他們認爲這種擺動的強度表示這顆行星的體積是地球的三倍。
At the time, the discovery of Earth-like planets around Gliese 581 caught the public imagination.
繞Gliese 581運行的類地行星發現之後，激發了公衆的想象力。
Documentary-maker RDF and social-networking site Bebo used a radio telescope in Ukraine to send a powerful focused beam of information - 500 messages from the public in the form of radio waves - to Gliese 581.
英國RDF電視傳媒和社交網站Bebo使用烏克蘭的無線電天文望遠鏡將以無線電方式收集的500條來自大衆的信息發送了給了Gliese 581。
And the Australian science minister at the time organised 20,000 users of Twitter to send messages towards the distant solar system in the wake of the discoveries.
澳大利亞的科學部長還組織2萬多名的推特用戶給遙遠的太陽系發送信息。
Other exoplanets have previously been doubted, most notably Alpha Centauri Bb, the closest Earth-sized world to us, which some scientists claim could just be noise in the data.
之前其他很多外星球的存在都被質疑過，最著名的就是與地球大小相當、離我們最近的Alpha Centauri Bb，一些科學家稱它的發現只是源於數據干擾。
