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Astronomers have confirmed the existence of an Earth-like planet in the "habitable zone" around a star, BBC reported.

The planet, Kepler 22-b, lies about 600 light-years away, is about 2.4 times the size of Earth and has a temperature of about 22 degrees Celsius.

However, the team does not yet know if Kepler 22-b is made mostly of rock, gas or liquid.

Kepler 22-b lies at a distance from its sun about 15% less than the distance from the Earth to the Sun, and its year takes about 290 days.

（點擊BBC網站查看原文）

天文學家發現“另一個地球”

???????據英國廣播公司報道，天文學家確認發現一顆類似地球的行星，該行星處于“可居住帶”，圍繞一顆恒星旋轉。

???????這顆行星叫開普勒-22b，距離地球600光年，約為地球體積的2.4倍，氣溫約22攝氏度。

???????但是，科研團隊尚不清楚該行星的主要組成物質是巖石、氣體還是液體。

???????它與自身繞轉的恒星距離比地球與太陽之間的距離短15%，每年大概為290天。

(China.org.cn December 7, 2011)