科學(xué)家們首次捕捉到來(lái)自太陽(yáng)的沖擊波

科學(xué)家們首次捕捉到來(lái)自太陽(yáng)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(yáng)可能是我們?cè)谔?yáng)系中最忠實(shí)的朋友，這顆黃色矮星將我們整個(gè)太陽(yáng)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(gè)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(shí)上，太陽(yáng)有時(shí)會(huì)以巨大的沖擊波震動(dòng)物體，這些沖擊波從它熾熱的中心爆發(fā)出來(lái)，并傳播到我們太陽(yáng)系的邊緣地帶。美國(guó)宇航局的科學(xué)家們第一次觀察并記錄了一個(gè)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(wù)(MMS)記錄下來(lái)的。MMS是一個(gè)四衛(wèi)星系統(tǒng)，設(shè)計(jì)用于探測(cè)帶電粒子在太空中的運(yùn)動(dòng)。美國(guó)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(cè)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(xué)家們?cè)凇兜厍蛭锢硌芯靠臻g物理學(xué)雜志》上發(fā)表的一篇論文中，用這些數(shù)據(jù)描述了這些改變空間的沖擊是如何產(chǎn)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(yáng)會(huì)釋放出帶電粒子流，即太陽(yáng)風(fēng)。因?yàn)檫@些流以不同的速度流動(dòng)，一些粒子會(huì)趕上另一些。當(dāng)它們這樣做的時(shí)候，它們的能量通過(guò)電磁波傳遞，沖擊波就產(chǎn)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(wú)碰撞的粒子,因?yàn)閰⑴c沖擊-即太陽(yáng)風(fēng)粒子主要是與電場(chǎng)和磁場(chǎng)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(xué)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(xiàn)象與地球上超音速噴氣式飛機(jī)以高于空氣音速的速度飛行時(shí)產(chǎn)生的沖擊波進(jìn)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(lái)自太陽(yáng)的沖擊波要難探測(cè)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(shí)，MMS衛(wèi)星也花了4年時(shí)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(yáng)并不是沖擊波的唯一來(lái)源;遙遠(yuǎn)的恒星甚至黑洞也會(huì)產(chǎn)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(yáng)對(duì)一切都有著深遠(yuǎn)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(qiáng)烈地提醒我們注意它的每一次爆發(fā)。