In November 2010, NASA announced the discovery of a strange, never-before-seen galactic object: two gigantic gaseous bubbles,
2010年11月，NASA宣布发现了一个以前从未见过的奇怪的星系物体：两个巨大的气泡，
each emanating an impressive 25,000 light years from the center of our home galaxy, the Milky Way.
每个泡从我们家园星系——银河系中心，辐射出令人印象深刻的 25,000 光年。
Inside the structures, named the Fermi Bubbles, streams of high energy particles traveling faster than the surrounding medium, collide with dust, gas,
在被命名为费米泡泡的结构内，高能粒子流的速度比周围介质更快，与尘埃、气体和光碰撞，
and light, to create gamma rays, the most energetic form of light.
产生伽玛射线，这是能量最强的光。
Astronomers were perplexed.
天文学家们感到困惑。
While gamma rays are not uncommon in space, radiation of this magnitude had only been observed in distant galaxies.
尽管伽玛射线在太空中并不罕见，但这种强度的辐射仅有在遥远的星系中观察到。
And they are typically produced by large-scale powerful events, like explosions of supernova.
它们通常由大规模的强力事件产生，比如超新星爆炸。
Yet, compared to our galactic neighbors, the center of the Milky Way and the supermassive black hole that resides within it,
然而，与我们的银河系邻居相比，银河系中心以及其中的超大质量黑洞
was always thought to have been relatively calm.
一直被认为是相对平静的。
So, what was the powerful event that created these massive structures?
那么，是什么强力事件创造了这些庞大的结构？
And is the center of our galaxy not so sleepy after all?
而且，我们的银河系中心是否真的如此宁静？
A clue to answering these questions came in December 2020, when astronomers announced the discovery of yet another set of radiating spheres.
回答这些问题的线索出现在 2020 年 12 月，当天文学家宣布发现了另一组辐射球。
Entitled the eROSITA bubbles, these structures are even wider, extending nearly half the distance of the entire Milky Way in both directions,
这些被称为 “eROSITA 气泡” 的结构更加宽广，几乎延伸到整个银河系的一半距离，
and fully encapsulating the Fermi Bubbles.
并完全包裹了费米泡泡。
They emit soft X-rays, which have frequencies lower than gamma rays, but are still highly energetic forms of light.
它们发出的软X射线的频率低于伽玛射线但仍然是高能的光。
Astronomers quickly surmised that the overlapping bubbles most likely share a single origin.
天文学家迅速推测，这些重叠的气泡很可能有一个共同的起源。
And the event that formed them must have generated a massive amount of energy— approximately 1 million times that which the Sun will produce during its entire lifetime.
而且，形成它们的事件一定产生了大量的能量，约为太阳在其整个寿命周期内产生能量的一百万倍。
Based on the speed of the jets of energetic electrons within the bubbles,
根据气泡内高能电子射流的速度，
they calculated the event most likely took place less than 3 million years ago.
他们计算出这一事件很可能发生在不到 300 万年前。
This is relatively recent compared to the galaxy's 13-billion-year lifespan,
与银河系 130 亿年的寿命相比， 这是一个相对较新的事件，
and means our early ancestors might have even witnessed the powerful event, as a gigantic ball of heated mass illuminating the night sky.
这意味着我们的早期祖先甚至可能亲眼目睹了这一强大的事件，如一个巨大的受热物质球照亮夜空。
But what exactly was the powerful event?
但是，究竟是什么样的强大事件？
Two theories quickly emerged about what could have created the bubbles and the high energy particle jets within.
关于是什么原因造成了这些气泡和内部的高能粒子射流，很快涌现出两种理论。
And both are still debated today.
而且，这两种理论至今仍在争论中。
The first theory is that the bubbles stem from a recent massive burst of star formation toward the center of our galaxy.
第一种理论认为，这些气泡源于最近在银河系中心爆发的大规模恒星。
Newly forming stars produce a vast outflowing of hot gas, called stellar winds.
新形成的恒星会导致大量的热气体流出，被称为恒星风。
Meanwhile, young massive stars die quickly, causing energetic supernova explosions.
同时，年轻的巨大恒星会迅速死亡，引发高能超新星爆炸。
Stellar winds combined with these explosions can lead to the formation of large-scale galactic winds.
恒星风与这些爆炸相结合，可以形成大规模的星系风。
These galactic winds can push away the surrounding material, creating gigantic bubbles.
这些星系风可以推开周围的物质，从而形成巨大的气泡。
The second theory is that the structures are the result of a powerful outburst from the supermassive black hole at the center of our galaxy.
第二种理论认为，这些结构是我们银河系中心的超大质量黑洞强力爆发的结果。
Named Sagittarius A*, this black hole lives up to its title of supermassive, as it's approximately 4 million times the mass of the Sun.
这个被命名为人马座A*的黑洞名副其实地拥有超大质量的称号，因为它的质量大约是太阳的400万倍。
And scientists have documented similar jets of energy emanating from similar black holes in other distant active galaxies.
科学家还记录了来自其他遥远活跃星系中类似黑洞的类似能量射流。
These jets are found in active galactic nuclei known as quasars, and they're created as dust and gases rapidly fall into the feeding black hole.
这些射流出现在被称为类星体的活动星系核中，它们随着尘埃和气体迅速坠入的黑洞。
This gathers hot ionized gas around the vicinity, which is then ejected from the center at ultra-fast velocities.
这会在附近聚集热的电离气体，然后以超快的速度从中心喷射出来。
This theory suggests that Sagittarius A*, which is thought to be relatively quiet, may have been active relatively recently.
这一理论表明，被认为相对安静的射手座A*最近可能比较活跃。
And it begs the question: will it wake up again?
这就引出了一个问题：它会再次苏醒吗？
Scientists use supercomputers to run what is known as hydrodynamic numerical simulations,
科学家使用超级计算机来运行所谓的流体动力学数值模拟，
where different physical conditions that may have led to bubble formation are explored.
探索可能导致气泡形成的不同物理条件。
While several results suggest that extreme outbursts from Sagittarius A* likely contributed to the creation of the bubbles,
虽然有几个结果表明，人马座A* 的极端爆发可能导致了气泡的产生，
it remains to be seen whether past star formations may have also played a role.
但过去的恒星形成是否也发挥了作用尚有待观察。
Other simulations show evidence of other contributing factors, like the influence of circumgalactic medium winds from outside our galaxy,
其他模拟显示了其他影响因素的证据，例如来自银河系外的环星系中的风的影响，
which may explain some of the bubbles' unique features.
这或许可以解释这些气泡的一些独特特征。
These computational simulations will only get more precise as we continue to launch more sensitive and dynamic telescopes into space.
随着我们继续向太空发射更灵敏、更具动态性的望远镜，这些计算模拟将变得更加精确。
But whatever answers we unlock will undoubtedly lead to more surprises about our mysterious, and perhaps not so calm, galaxy.
但无论我们解开了什么答案，无疑都将给我们这个神秘而可能并不那么平静的星系带来更多惊奇。
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