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来源：雅诚德英语网
Gliese 581g has a mass three to four times Earth's, the researchers estimated.
研究人员估测gliese 581g行星的质量大约是地球的3到4倍。
Gliese 581g has a mass three to four times Earth's, the researchers estimated.
研究人员估测gliese 581g行星的质量大约是地球的3到4倍。