According to NASA, a total eclipse, when the moon passes between the earth and the sun, is only visible from a narrow strip - about 150 km wide - of the Earth's surface at any one time.

据美国宇航局所说，整个日食过程，即在月亮位于地球和太阳之间的时间内，也仅仅在地表一条约150公里宽的狭长地带的某一时刻可以观看到。

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For scale, the large impact crater in lower right corner is about 18.5 miles, or 30 km, wide.

右下角的巨大陨石坑按比例宽约18.5英里，或30公里。

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The reservoir is 400 km long, 15 km wide and 100 m deep.

整座水库长400千米，宽15千米，深100米。

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The 15 km-wide strip will run 55 km from the Petronas Towers in Kuala Lumpur to the new international airport at Sepang near the Negri Sembilan state border.

CNN: The Center of the World?

Early of the Lawrence Livermore National Laboratory, California, proposed siting a vast, 2000 km-wide glass deflecting panel at the "inner Lagrange point" between the Earth and the sun, the latter diverting the sun's rays away from the Earth's atmosphere.

CNN: The shield of Ra: Could solar reflection save the planet?