一顆罕見的恒星逃離了銀河系中心的超大質(zhì)量黑洞

一顆罕見的恒星逃離了銀河系中心的超大質(zhì)量黑洞

This may be the luckiest star in the universe.

這可能是宇宙中最幸運(yùn)的恒星。

After all, it's not every day that anything escapes the clutches of a supermassive black hole, much less a massive celestial body.

畢竟，并不是每天都有什么東西能逃脫超大質(zhì)量黑洞的魔爪，更不用說一個(gè)巨大的天體了。

In fact, in a research paper published online in Cornell's arXiv, scientists suggest the "hyper-velocity" star dubbed S5-HVS1 may be the first one detected exiting from a black hole.

事實(shí)上，在康奈爾大學(xué)網(wǎng)站上發(fā)表的一篇研究論文中，科學(xué)家們提出，這顆被稱為S5-HVS1的“超高速”恒星可能是第一個(gè)從黑洞中被探測(cè)到的恒星。

And what an exit it was. In the paper, partly titled "The Great Escape," researchers suggest it's moving at the ferocious rate of more than 1,000 miles per second.

這是一個(gè)多么好的出口啊。在這篇部分名為《大逃亡》的論文中，研究人員表示，它正在以每秒1000多英里的驚人速度移動(dòng)。

The center of the galaxy isn't the kind of place stars emerge from in one piece. (Photo: sripfoto/Shutterstock)

The star likely needed every ounce of that momentum to make its "great escape" from no less than the supermassive black hole that lurks at the heart of our own galaxy, the Milky Way. That area of space is better known for devouring stars than setting them free.

這顆恒星可能需要每一盎司的動(dòng)量才能從潛伏在我們銀河系中心的超大質(zhì)量黑洞中“大逃亡”出來。這片區(qū)域更出名的是吞噬恒星，而不是釋放它們。

And that would be largely due to the supreme reign of a supermassive black hole, dubbed Sagittarius A* (pronounced "Sagittarius A star") — a gravitational golem with a mass around 4 million times that of our sun.

這在很大程度上要?dú)w功于一個(gè)超大質(zhì)量黑洞——人馬座a *(發(fā)音為“人馬座a星”)的至高無上的統(tǒng)治地位。人馬座a *是一個(gè)引力傀儡，其質(zhì)量大約是太陽的400萬倍。

Researchers made the "serendipitous discovery" while working on the Southern Stellar Stream Spectroscopic Survey, a collaboration of more than 30 international scientists that maps stellar streams in the Milky Way.

這項(xiàng)“意外發(fā)現(xiàn)”是研究人員在進(jìn)行“南方恒星流光譜調(diào)查”時(shí)發(fā)現(xiàn)的。“南方恒星流光譜調(diào)查”是由30多位國際科學(xué)家合作完成的，他們繪制了銀河系的恒星流圖。

A close-up photo of the black hole at the heart of Sagittarius A*. (Photo: National Science Foundation)

One of those streams suggested a star was hurtling outward from the very heart of the galaxy.

其中一條流表明，一顆恒星正從銀河系的中心向外疾馳。

"When integrated backwards in time, the orbit of the star points unambiguously to the Galactic Centre, implying that S5-HVS1 was kicked away from Sgr A* with a velocity of $1,800 km/s and travelled for $4.8 M years to the current location," the study abstract reads.

該研究摘要寫道:“如果時(shí)光倒流，這顆恒星的軌道明確指向銀河系中心，這意味著S5-HVS1以1800公里/秒的速度被Sgr A*踢出，并以480萬美元的速度運(yùn)行到目前的位置。”

And it's not just that the star muscled its way out of the grasp of Sgr A*. The galaxy's core happens to be riddled with smaller but still powerful black holes. In fact, a recent study pegs the black hole population at the heart of our galaxy at somewhere around 10,000.

這不僅僅是因?yàn)楹阈菑腟gr A*的掌控中掙脫出來。星系的核心碰巧布滿了更小但仍然強(qiáng)大的黑洞。事實(shí)上，最近的一項(xiàng)研究表明，位于銀河系中心的黑洞數(shù)量約為1萬個(gè)。

So what does a black-hole dodging star do for an encore — besides, of course, spending the next few millions years congratulating itself?

那么，一顆正在躲避黑洞的恒星要如何再來一次呢?

Even this star appears a little directionless now that its long struggle with dark powers is at an end. According to the researchers, it has spent the last 4.8 million years roaring through space. Maybe that's how long it takes — and how fast one has to go — before being comfortable with a black hole in the rearview mirror.

即使是這顆恒星，在它與黑暗力量的長期斗爭結(jié)束后，也顯得有點(diǎn)迷失了方向。據(jù)研究人員稱，在過去的480萬年里，它一直在太空中咆哮。也許這就是在汽車后視鏡上發(fā)現(xiàn)黑洞之前需要的時(shí)間和速度。