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          土星环并非土星天生就有 而是后期升级的装备

          kira86 于2019-02-26发布 l 已有人浏览
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          土星环让土星在太阳系显得十分与众不同,大家一眼便能认出它,但科学研究发现,土星环并非与土星一样形成于太阳系早期,而是后期升级的装备。
            小E英语欢迎您,请点击播放按钮开始播放……

          土星光环.jpg
          Saturn's Blingy Rings Are a Recent Upgrade

          土星的光环是“最近”升级的

          When it comes to Saturn, it's the rings that render the planet instantly recognizable. But it turns out that Saturn was not always so elaborately adorned. Data from the final orbits of the Cassini mission indicate that Saturn's rings were a relatively recent addition...forming a scant 100 [million] to 10 million years ago. The findings are in the journal Science.

          说到土星,是土星的光环让我们一眼就能认出它。但原来,土星并非一直都装饰得那么精致的。卡西尼号任务的最终轨道数据表明,土星的光环是一个相对较近的新增附属物,大约形成于1亿到1000万年前。研究结果发表在《科学》杂志上。

          During what's been called the "grand finale" phase of the Cassini mission, the spacecraft repeatedly dove through the gap between the top of Saturn's clouds and the innermost edge of its rings. These flybys allowed researchers to separate the gravitational effects of the planet and its accessories...which led to a more precise measurement of the rings' mass.

          在?#24576;?#20026;卡西尼号任务的“华丽终场”(此后便以“自杀”的方式坠入土星大气层)阶段,飞船反复在土星云的顶部和土星环的最内侧边缘之间的空?#37117;?#39134;跃。这些飞跃使得研究人员能隔开行星及其配饰(光环)的引力效应,从而更精?#36820;?#27979;量出土星环的质量。

          Their mass was the missing piece of the puzzle to determine their age.

          “土星环的质量是?#33539;?#23427;们形成时间的因素中?#31508;?#30340;一环。”

          Daniele Durante, a postdoc at Sapienza University in Italy, who analyzed the data.

          意大利罗马大学(Sapienza University of Rome)的博士后丹尼尔·杜兰特分析了这些数据。

          The rings are made up mostly of ice with a small fraction of impurities. About one or two percent of the total rings' mass. These impurities consist of rocky material coming from outer space. Since these impurities are accumulated over time, these allow us to relate the total mass of the rings with their age.

          “这些光环大部分是由冰和少量杂质构成,(杂质)约占整个光环质量的1%到2%之间。这些杂质是由来自外太空的岩石物质构成的。由于这些杂质是在时间的长河里堆积的,所以我们可以将这些光环的总质量和它们的年龄相联系起?#30784;?rdquo;

          Durante and his colleagues found that Saturn's bling has a combined mass of about one-and-a-half to two times 10 to the 19th kilograms...that's less than half the mass of its smallest moon. And when they crunched the numbers, the data suggested an age of no more than 100 million years. To put that in context, remember, dinosaurs roamed the earth from about 200 million years ago until 65 million years ago. And Saturn itself, like planet Earth, formed early in the life of the solar system, about 4.5 billion years ago.

          杜兰特和他的同事们发现,土星耀眼光环的总质量约为10的19次方(即19个10相乘)公斤的1.5到2倍,它的质量还不到它最小卫星的一半。当他们仔细研究这些数据时,数据显?#37202;?#24180;龄不超过1亿年。请联系下当时的背景,不要忘了,从2亿到6500万年前,恐龙一直在地球上四处游?#30784;?#22303;星本身像行星地球一样形成于太阳系早期——大约45亿年前。

          Therefore, the ring's formation came long after that of the planet.

          “因此,这个光环的形成时间?#23545;?#26202;于行星(土星)的形成时间。”

          The youthful accoutrement might have come from a captured comet or a pulverized moon. But no matter how they were made, the rings really do make Saturn a solar system standout.

          这个“年轻的装饰”可能来自一颗被捕获的彗星或一颗?#29615;?#30862;的卫星。但无论光环是如何形成的,土星环?#32933;?#20351;其在太阳系中脱颖而出。

          - Karen Hopkin

          小e英语Jewel翻译!

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