防紫外線的魔毯(雙語音頻)
詼諧的語言，生動的內(nèi)容一分鐘快速掌握科技最新動態(tài)
Water Blankets Forming Planets
In 2008 astronomers discovered surprising amounts of water molecules where planets were forming near young stars. But how, they wondered, could those molecules survive? They should have been destroyed by ultraviolet radiation. In theory, planetary dust could block out UV rays, but the dust was bound up in the creation of those young planets. So what's protecting the water? Now researchers at the University of Michigan believe they have the answer, which they published in the December 18th edition of the journal Science.
2008年，天文學(xué)家在年輕恒星附近形成的行星上發(fā)現(xiàn)了數(shù)量驚人的水分子。可這些水分子怎么可能存活下來呢？他們本應(yīng)被紫外線殺死的了啊。理論上行星星塵可以把紫外線擋在外面，可在這些年輕行星的形成過程中，星塵是擠成一團(tuán)的。這么說來，到底是什么東西在保護(hù)水分子呢？現(xiàn)在密歇根大學(xué)的研究者們相信自己找到了答案，并將其研究成果刊登在12月18號的《科學(xué)》雜志上。
The regions where planets are being created are incredibly chemically productive, rapidly generating new compounds. According to the researchers, some water molecules surround the almost-planet dust and act as almost a sacrificial layer. The water molecules absorb the ultraviolet rays—and, though those molecules are destroyed, the embryonic planet is shielded. And the region is producing water faster than the protective layer is being destroyed.
行星正在形成的區(qū)域不斷迅速產(chǎn)生著新的化合物，其化學(xué)活性高得令人難以置信。研究者表示，一部分水分子包裹著未來的行星星塵，充當(dāng)犧牲者的角色——這些水分子吸收了紫外線，所以即使它們被殺死了，處于形成初期的行星還是受到了保護(hù)。更何況水分子生成的速度比被殺死的速度要快。
The scientists say this action is similar to our ozone layer, which blankets us with protective shielding from UV radiation. They tested this idea in computer models and found that the results mirrored the observations. Seems that having water when a planet’s finished requires sacrificing some in the process.
科學(xué)家們說水分子的這種行為與我們地球的臭氧層類似，都是保護(hù)我們不受紫外線侵害的“毯子”。 他們建立電腦模型對這一推測進(jìn)行檢驗，發(fā)現(xiàn)結(jié)果正好印證了他們的觀察?？磥硇行强焱耆尚偷臅r候，是需要一些水分子做出犧牲的。
—Cynthia Graber
