Ascertaining that a star has exactly the sun's age is impossible, he says, and many unrelated stars share its chemical composition.

他继续补充道，找到一个和太阳有相同年龄的恒星根本没有可能，而且很多和太阳没有关系的恒星也有着与其相同的化学构成。

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Professor Jane Evans, who traces the birthplace of Bronze Age skeletons using a chemical analysis of teeth, believes the visitors were travelling to Britain specifically to see Stonehenge.

简·埃文斯（Jane Evans）教授通过化学手段对牙齿进行分析，确定了男孩的出生地，她相信这个孩子来到英国，就是为了一睹巨石阵的真容。

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To get the age estimates, Nielsen and his team used a complex system that combines chemical tests, mathematical models and growth measurements.

为了估算年龄，尼尔森及其小组采用了一种结合化学试验、数学模型和生长测量的复杂系统。

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(OMITTED) Remais,an assistant professor at Emory University's Rollins School of Public Health in Atlanta, He says the growing economy is fueling environmental risks such as air pollution and chemical toxins, while age-old environmental challenges remain.

VOA: standard.2010.04.07

That's because the sound they make depends on their age, size and chemical composition.

BBC: Team records 'music' from stars

So how is it that the rubes, with their grease-stained hands, reeking of the smell of manure or chemical fertilizers, have outperformed the darlings of the information age?

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