The molecules emit the infrared light that they have absorbed ultraviolet radiation from the star or have been heated by the wind from the star.

氢分子发出红外线的原因是它们吸收了恒星发出的紫外线，或者是受到了恒星喷发的炽热气体流的加热。

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The supernova explosions that create and spread heavy elements also unleash a torrent of high-energy radiation: gamma rays, X-rays, and ultraviolet light.

创造并散播重元素的超新星爆发同样释放出一股高能辐射的激流：伽玛射线，X射线，紫外线。

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Swirls of green in Hubble's ultraviolet and visible-light view reveal hydrogen and sulfur gas that have been heated and ionized by intense ultraviolet radiation from the Trapezium's stars.

紫外线成像显示出的绿色漩涡以及可见光形成的图像揭示了氢和硫磺气体的存在，它们受发自四边形的强紫外线的辐射而变热并形成等离子体。

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When it is ground into nanoparticles it can still block harmful ultraviolet radiation, but it allows visible light to pass straight though, which means modern sunscreens can appear completely transparent, while offering the same protection as the old white stuff.

ECONOMIST: The risk in nanotechnology