To measure the difference in elevation between poles, surveyors used an optical level—a telescope on a level base—placed halfway between the poles.

为了测量两极之间的高程差，测量员在两极中间的一个水平基座上使用了光学水准望远镜。

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When combined, the data collected from the dishes will provide a level of detail some 10 times sharper than the Hubble Space Telescope.

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The Chilean desert's lack of humidity was a big reason for the telescope's placement, 16, 400 feet above sea-level, aiding precision of the scope.

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