什么东西正在吞噬参宿四的光?

The star known as Betelgeuse used to be one of the brightest objects in our night sky. In fact, it was easily discernible to the naked eye, gleaming brightly from the shoulder of the constellation Orion.

被称为参宿四的恒星曾经是我们夜空中最亮的物体之一。事实上，肉眼很容易就能分辨出来，它在猎户座的肩膀上闪闪发光。

Betelgeuse, also known as Alpha Orionis, as seen through a telescope. (Photo: Cristian Cestaro/Shutterstock)

And that's to be expected from a star that's not only relatively close to us, but also classified as a red supergiant, puffing up about 700 times as wide as our own sun.

这是一颗不仅离我们相对较近，而且被归类为红色超级巨星的恒星，它的直径是我们的太阳的700倍。

But lately something has been eating Betelgeuse. According to a newly published paper from researchers at Pennsylvania's Villanova University, the star has turned down the lights dramatically in the last two months. Scientists say it's about 2.5 times fainter than its usual brilliant self — going from the ninth brightest object in the sky to the 23rd.

但最近有东西一直在削减参宿四的亮度。宾夕法尼亚维拉诺瓦大学的研究人员最近发表的一篇论文称，在过去的两个月里，这颗恒星戏剧性地关闭了灯光。科学家们说，它的亮度是平常亮度的2.5倍——从天空中第九亮的物体到第23亮的物体。

As a variable star, Betelgeuse waxes and wanes in brightness as part of a natural cycle. But it's losing its shine so fast, astronomers suspect it may be primed to go supernova.

作为一颗变星，参宿四的亮度会随着自然周期的变化而变化。但它的光芒消失得如此之快，天文学家怀疑它可能准备成为超新星。

When a star comes to an end, it often dims before unleashing a luminosity that's exponentially greater than usual. Supergiants don't typically die boring deaths.

当一颗恒星走到尽头时，它通常会在释放出比平时大得多的光度之前变暗。超级巨人一般不会无聊地死去。

And if Betelgeuse does explode, its proximity to Earth would make it a blinding beacon in the sky, day or night.

如果参宿四真的爆炸了，它与地球的距离将使它成为天空中令人目眩的灯塔，无论白天还是黑夜。

"I personally think it's going to bounce back, but it's fun to watch stars change," lead study author Ed Guinan tells CNN. Although, he adds, if Betelgeuse keeps losing its shine, "all bets are off."

“我个人认为它会反弹，但看着明亮的恒星改变是很有趣的，”该研究的主要作者Ed Guinan告诉CNN。尽管如此，他补充说，如果参宿四继续失去它的光芒，“所有的赌注都输了。”

Our sun barely registers as a pinprick compared to Betelgeuse. (Photo: Aliona Ursu/Shutterstock)

Guinan, who has been observing Betelgeuse for decades, says the star's distance from us makes an accurate diagnosis impossible.

吉南几十年来一直在观察参宿四，他说，由于参宿四离我们的距离太远，所以无法做出准确的诊断。

"What causes the supernova is deep inside the star," Guinan adds.

“超新星形成的原因是在恒星的内部深处，”吉南补充道。

The thing is, since it's 700 light-years from Earth, Betelgeuse may have already issued its last sigh. That's because the news of its demise would take 700 years to reach us. But if its sudden dimming does suggest the red giant is going the way of the supernova, Earthlings still get treated to a spectacular light show — even if it's not exactly a "live" event.

问题是，由于它距离地球700光年，参宿四可能已经发出了它的最后一声叹息。这是因为它灭亡的消息需要700年才能传到我们这里。但是，如果它的突然变暗确实表明这颗红巨星正在走向超新星的道路，那么地球人仍然可以看到一场壮观的灯光秀——即使这不是一场真正的“现场”活动。

What's more, the shock wave, radiation and celestial debris from Betelgeuse's passing wouldn't reach our solar system's doorstep for about 6 million years, according to National Geographic. And our ever-protective sun would hold up an umbrella, to make sure Earth doesn't get rained with star innards — leaving humans to bask safely in the cosmic pyrotechnics.

更重要的是，据《国家地理》杂志报道，参宿四经过地球时产生的冲击波、辐射和天体碎片大约600万年后才到达我们太阳系的门口。我们那永远保护着我们的太阳会撑起一把伞，以确保地球不会因为内部的恒星而下雨——让人类安全地沐浴在宇宙的烟火之中。

"It would be so incredibly cool!" astronomer Sarafina Nance, who was not involved with the research, tells National Geographic. "By far and away the most incredible thing to happen in my life."

没有参与这项研究的天文学家萨拉菲娜·南斯在接受《国家地理》杂志采访时表示:“这真是太酷了!”“这是我一生中最不可思议的事情。”