How does cosmic dust form in supernova explosions
Pegasus Voice | No.2

文字：网络  |   朗诵：Michael Wang（11年级）

 

 

Hello everyone. This is Michael here from 11th grade of Pegasus California School. In today’s Pegasus Voice, I am going to talk about the topic that how does cosmic dust form in supernova explosions. Enjoy in science, let’s get start.

大家好。这里是来自11年级博格思学校的Michael。在今天的博格思之声中，我要讲的主题是宇宙尘埃是如何在超新星爆炸中形成的。享受科学，让我们开始吧。

There are billions of stars and planets in the universe. A star is glowing sphere of gas, while planets like Earth are made up of solids. 

宇宙中有数十亿颗恒星和行星。 恒星是发光的气体球体，而像地球这样的行星是由固体组成的。

The planets are formed in dust clouds that swirled around a newly formed star. Dust grains are composed of elements like carbon, silicon, oxygen, iron, and magnesium. But where does the cosmic dust come from?

这些行星是在围绕新形成的恒星旋转的尘埃云中形成的。尘埃颗粒是由碳、硅、氧、铁和镁等元素组成的。 但是宇宙尘埃从何而来呢?

New research from the Niels Bohr Institute at the University of Copenhagen and Aarhus University shows that not only can grains of dust form in gigantic supernova explosions, they can also survive the subsequent shockwaves they are exposed to. 

哥本哈根大学尼尔斯玻尔研究所和奥尔胡斯大学的新研究表明，灰尘颗粒不仅可以在巨大的超新星爆炸中形成，它们也可以在暴露于随后的冲击波中幸存下来。

The results are published in the scientific journal, Nature. How the cosmic dust is formed has long been a mystery to astronomers. 

研究结果发表在科学杂志《自然》上。对天文学家来说，宇宙尘埃是如何形成的一直是个谜。 

The elements themselves are formed out of the glowing hydrogen gas in stars. The hydrogen atoms fuse together into heavier and heavier elements and in the fusion process the star emits radiation in the form of light, that is, energy. 

这些元素本身是由恒星中发光的氢气形成的。 氢原子熔合在一起，形成越来越重的元素，在熔合过程中，恒星以光的形式发出辐射，也就是能量。

When all the hydrogen is exhausted and no more energy can be extracted, the star dies and giant clouds of gas are slung out into space, where they are recycled into new stars in a vast cosmic cycle. 

当所有的氢都耗尽，无法再提取能量时，恒星就会死亡，巨大的气体云被抛入太空，在巨大的宇宙循环中，它们被循环成新的恒星。

The heavy elements are primarily formed in supernovae, which are massive stars that die in a gigantic explosion. But how do the elements grow into 'larger clumps' like cosmic dust grains?

重元素主要是在超新星中形成的，超新星是在巨大爆炸中死亡的大质量恒星。 但是这些元素是如何长成像宇宙尘埃颗粒那样的“大团块”的呢?

"The problem has been that even though dust grains composed of heavy elements would form in supernovae, the supernova explosion is so violent that the grains of dust may not survive. But cosmic grains of significant size do exist, so the mystery has been how they are formed and have survived the subsequent shockwaves. Our research casts new light on this -- both on how dust is formed and how it survives the shockwaves," 

“问题是，即使由重元素组成的尘埃颗粒会在超新星中形成，但超新星爆炸如此剧烈，尘埃颗粒可能无法存活。 但大尺寸的宇宙颗粒确实存在，所以它们是如何形成的以及如何在随后的冲击波中存活下来的谜团一直存在。 我们的研究为这一问题提供了新的线索——尘埃是如何形成的，以及它是如何在冲击波中幸存下来的，”

explains Professor Hjorth, head of the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen.

哥本哈根大学尼尔斯·玻尔研究所黑暗宇宙学中心主任赫约斯教授解释道。

The researchers observe supernovae using the astronomical instrument X-shooter on the European Southern Observatory's Very Large Telescope in Chile. Part of the X-shooter was developed and built by Danish researchers at the Niels Bohr Institute and what is special about the instrument is both that it is extremely sensitive and the three observe all light at once -- from ultraviolet to visible light to infrared light. This is extremely important when observing phenomena in the distant universe.

研究人员使用位于智利的欧洲南方天文台甚大望远镜上的X-射线器天文仪器来观测超新星。x -射线器的一部分是由丹麦尼尔斯·玻尔研究所的研究人员开发和建造的，该仪器的特别之处在于它非常敏感，而且这三种仪器可以同时观察所有的光——从紫外线到可见光再到红外光。 这在观察遥远宇宙的现象时是非常重要的。

Jens Hjorth explains that first they had to wait for the right, luminous supernova to explode. They were lucky and when it happened they initiated an observing campaign. This was a very bright supernova, 10 times brighter than the average supernova. The exploding star itself had been very massive, more than 40 times the mass of the Sun. 

延斯·赫约斯解释说，首先，他们必须等待合适的发光超新星爆炸。 他们很幸运，当这种情况发生时，他们发起了一场观察运动。 这是一颗非常明亮的超新星，比普通超新星亮10倍。 爆炸的恒星本身质量非常大，是太阳质量的40多倍。

Researchers from the Dark Cosmology Centre at the Niels Bohr Institute, Aarhus University, and NASA, among others, followed the explosion right from the start and the following 2½ years and analysed the light from the very bright new star.

来自尼尔斯玻尔研究所、奥尔胡斯大学和美国国家航空航天局的研究人员，以及其他研究人员，从爆炸开始到接下来的两年半时间，分析了这颗非常明亮的新恒星发出的光。