科學家們首次捕捉到來自太陽的沖擊波
The sun may be our most constant friend in the solar system, the yellow dwarf star that holds our entire solar system together.
太陽可能是我們在太陽系中最忠實的朋友,這顆黃色矮星將我們整個太陽系維系在一起。
But that doesn't mean it's always a steadying force.
但這并不意味著它總是一個穩(wěn)定力。
In fact, the sun shakes things up on occasion with massive shockwaves that burst from its fiery heart and travel to the very fringes of our solar neighborhood. And, for the first time, NASA scientists have observed and recorded one shockwave's outward odyssey.
事實上,太陽有時會以巨大的沖擊波震動物體,這些沖擊波從它熾熱的中心爆發(fā)出來,并傳播到我們太陽系的邊緣地帶。美國宇航局的科學家們第一次觀察并記錄了一個沖擊波向外的奧德賽。
Charged particles carried by solar winds catch up to each other and result in a shockwave. (Photo: Goddard Space Flight Center/Conceptual Image Lab)
This particular shockwave was recorded in January 2018 by the Magnetospheric Multiscale Mission (MMS) — a four-satellite system designed to sniff out charged particles as they move through space. NASA just released a stunning footage, calling it the "first high-resolution measurements of an interplanetary shock."
這種特殊的沖擊波是2018年1月由磁層多尺度任務(MMS)記錄下來的。MMS是一個四衛(wèi)星系統(tǒng),設計用于探測帶電粒子在太空中的運動。美國宇航局剛剛公布了一段令人震驚的視頻,稱其為“第一次高分辨率測量星際沖擊”。
Scientists used the data to describe how these space-altering shocks are born in a paper published in the Journal of Geophysical Research Space Physics.
科學家們在《地球物理研究空間物理學雜志》上發(fā)表的一篇論文中,用這些數據描述了這些改變空間的沖擊是如何產生的。
They don't start off as shockwaves. Rather, the sun sends out streams of charged particles known as solar winds. Because these streams travel at different speeds, some particles catch up to others. And when they do, their energy is transferred through electromagnetic waves, and a shockwave is born.
它們一開始并不是沖擊波。相反,太陽會釋放出帶電粒子流,即太陽風。因為這些流以不同的速度流動,一些粒子會趕上另一些。當它們這樣做的時候,它們的能量通過電磁波傳遞,沖擊波就產生了。
"These types of shocks are 'collisionless' because the particles involved in the shock — i.e. the solar wind particles — primarily interact with the electric and magnetic fields and not in billiard-ball-like collision with other particles," lead author Ian Cohen of Johns Hopkins University explains to Newsweek.
“這些類型的沖擊是無碰撞的粒子,因為參與沖擊-即太陽風粒子主要是與電場和磁場相互作用而不是與其他粒子碰撞,”主要作者約翰·霍普金斯大學的伊恩•科恩向《新聞周刊》解釋。
Cohen compares the phenomenon to the shockwaves created on Earth when a supersonic jet moves faster than the speed of sound in the air.
科恩將這一現象與地球上超音速噴氣式飛機以高于空氣音速的速度飛行時產生的沖擊波進行了比較。
When supersonic jets break the sound barrier, they create a shockwave (Photo: NASA)
Shockwaves from the sun, however, are much more difficult to detect, requiring extremely precise sensors.
然而,來自太陽的沖擊波要難探測得多,需要極其精確的傳感器。
Even then, it took four years for MMS satellites to capture one in all its glory.
即使在那時,MMS衛(wèi)星也花了4年時間才捕捉到其中的一顆。
Our sun isn't the only source of shockwaves; distant stars and even black holes produce them, too.
我們的太陽并不是沖擊波的唯一來源;遙遠的恒星甚至黑洞也會產生它們。
But as the pillar of our space community, the sun impacts everything in profound ways, right down to the tiniest rock. And shockwaves, which can dramatically alter weather here on Earth, are very loud reminders that its every outburst is well worth heeding.
但作為我們太空社區(qū)的支柱,太陽對一切都有著深遠的影響,甚至影響到最小的巖石。沖擊波能極大地改變地球上的天氣,它強烈地提醒我們注意它的每一次爆發(fā)。