Cosmic rays of various kinds come through the air from outer space, but enormous quantities of radiation from the sun are screened off.

来自外太空的各种宇宙射线通过空气进入大气层，但来自太阳的大量辐射却被屏蔽了。

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As cosmic particles enter the atmosphere and bump into atoms of air, water, ice, rock or anything else that happens to stand in their way, they trigger telltale cascades of other particles.

随着那些宇宙粒子进入大气层，并且和空气，水，岩石或别的什么阻挡在他们飞行路径上的东西中的原子碰撞，它们就会触发其他粒子的级联反应。

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The radiation comes from space (cosmic rays) as well as natural radioactive materials found in the soil, water and air.

辐射来自于外层空间（宇宙射线），以及在土壤，水和空气中的天然放射性物质。

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Theory predicts that when cosmic rays (fast particles coming from outer space) collide with air molecules in the upper atmosphere, they should yield twice as many muon neutrinos as electron neutrinos.

ECONOMIST: Neutrinos