James Webb Space Telescope sees little red dots feeding black holes: 'This is how you solve a universe-breaking problem'

詹姆斯·韦伯太空望远镜看到小红点为黑洞提供食物：“这就是解决宇宙破坏问题的方法”

Astronomers may have "saved cosmology" by gathering the largest sample yet of some of the most ancient galaxies ever seen, the so-called "little red dots" observed by the James Webb Space Telescope (JWST).

天文学家可能已经“拯救了宇宙学”，因为他们收集了迄今为止观测到的一些最古老星系的最大样本，即詹姆斯韦伯太空望远镜（JWST）观测到的所谓的“小红点”。

The team behind this research found the majority of the ancient galaxies in their sample — which existed earlier than 1.5 billion years after the Big Bang — seem to host rapidly feeding, or "accreting," supermassive black holes.

这项研究背后的团队发现，在他们的样本中，大多数存在于大爆炸后15亿年前的古老星系，似乎都有快速喂养或“吸积”的超大质量黑洞。

The research should put an end to claims that the JWST has "broken cosmology" with its detection of shockingly bright early galaxies that seemed to contain more stars than would be expected so early in the universe's history. Instead, this new survey suggests that much of the light from these little red dots comes from the turbulent conditions generated by the feasting cosmic titans at their hearts.

这项研究应该结束JWST已经“打破了宇宙学”的说法，因为它发现了令人震惊的明亮的早期星系，这些星系似乎包含了比宇宙历史早期预期更多的恒星。相反，这项新的调查表明，这些小红点发出的大部分光来自于它们中心的宇宙巨兽所产生的湍流环境。

"We're confounded by this new population of objects that the JWST has found. We don't see analogs of them at lower redshifts [corresponding to smaller distances], which is why we haven't seen them prior to the JWST," team leader Dale Kocevski of Colby College said in a statement.

“我们对JWST发现的这些新天体感到困惑。科尔比学院的团队负责人戴尔·科切夫斯基在一份声明中说：“我们在较低的红移（对应于更小的距离）上没有看到类似的现象，这就是为什么我们在JWST之前没有看到它们的原因。”

"There's a substantial amount of work being done to try to determine the nature of these little red dots and whether their light is dominated by accreting black holes."

“我们正在做大量的工作，试图确定这些小红点的性质，以及它们的光是否由吸积黑洞主导。”

Upon their discovery back in 2022, astronomers already knew that the JWST's little red dots represented a new galaxy type that had never been seen before. They were also baffled by how common these galaxies seemed to be in the early universe.

早在2022年发现时，天文学家就已经知道JWST的小红点代表了一种以前从未见过的新星系类型。他们还对这些星系在早期宇宙中的普遍程度感到困惑。

The team comprised their large sample of "little red dot" galaxies using data from the JWST surveys CEERS (Cosmic Evolution Early Release Science), JADES (JWST Advanced Deep Extragalactic Survey), the NGDEEP (Next Generation Deep Extragalactic Exploratory Public), and the RUBIES (Red Unknowns: Bright Infrared Extragalactic Survey).

该团队使用来自JWST调查CEERS（宇宙进化早期释放科学），JADES （JWST高级深河外调查），NGDEEP（下一代深河外探索公众）和红宝石（红色未知数：明亮红外河外调查）的数据组成了他们的大样本“小红点”星系。

Particularly important to this little red dots research was data from the aptly named RUBIES project.

对于这个小红点研究来说，特别重要的是来自ruby项目的数据。

This revealed to the team that approximately 70 percent of their sample galaxies showed evidence of gas whirling around at 2 million miles per hour (1,000 kilometers per second). This is a clear sign of a flattened cloud of gas and dust called an accretion disk feeding a supermassive black hole in a central galactic region known as an active galactic nucleus (AGN).

这向研究小组揭示了大约70%的样本星系显示出气体以每小时200万英里（每秒1000公里）的速度旋转的证据。这是一个清晰的迹象，表明一个被称为吸积盘的扁平气体和尘埃云正在为一个超大质量黑洞提供食物，这个黑洞位于一个被称为活动星系核（AGN）的星系中央区域。

Little red dot galaxies owe some of their coloration to a phenomenon called "redshift." As light from a galaxy travels toward Earth, the expansion of the universe stretches its wavelength, simultaneously lowering its frequency.

小红点星系的一些颜色要归功于一种叫做“红移”的现象。当来自星系的光向地球传播时，宇宙的膨胀会延长其波长，同时降低其频率。

This shifts the light toward the "red end" of the electromagnetic spectrum. The longer the light travels, the more extreme this redshift effect is. Thus, ancient galaxies are described as "high redshift galaxies."

这使得光向电磁波谱的“红端”移动。光传播的时间越长，这种红移效应就越极端。因此，古代星系被描述为“高红移星系”。

After traveling for many billions of years, light shifts into the near-infrared or infrared wavelengths, which are the wavelengths the JWST is designed to see.

在经历了数十亿年的旅行之后，光线转变为近红外或红外波长，这是JWST设计的波长。

"The most exciting thing for me is the redshift distributions. These really red, high-redshift sources basically stop existing at a certain point after the Big Bang," team member and University of Texas at Austin researcher Steven Finkelstein said. "If they are growing black holes, and we think at least 70% of them are, this hints at an era of obscured black hole growth in the early universe."

“对我来说最令人兴奋的是红移分布。这些真正的红色、高红移源基本上在大爆炸后的某个时刻停止存在，”德克萨斯大学奥斯汀分校的研究人员、团队成员史蒂文·芬克尔斯坦说。“如果它们正在形成黑洞，我们认为至少有70%的黑洞是这样的，这就暗示了早期宇宙中一个模糊的黑洞生长时代。”

You may have read headlines suggesting that "cosmology is broken" since the JWST started detecting these ancient little red dots.

自从JWST开始探测到这些古老的小红点以来，你可能读过这样的头条新闻：“宇宙学被打破了”。

That is because scientists have been scratching their heads about how early galaxies grew to contain stellar populations large enough to pump out so much light when the 13.8 billion-year-old cosmos was no more than 12% of its current age. This discovery could help explain that puzzle.

这是因为，当138亿年前的宇宙还不到现在年龄的12%时，早期星系是如何发展到包含足够大的恒星数量来发出如此多的光的，科学家们一直在挠头。这一发现可能有助于解释这个谜题。

AGNs are extremely bright due to the turbulence created in accretion disks by the incredible gravitational influence of supermassive black holes with masses equivalent to millions or billions of suns.

由于质量相当于数百万或数十亿个太阳的超大质量黑洞令人难以置信的引力影响在吸积盘中产生的湍流，AGN极其明亮。

Thus, much of the light from these galaxies could be coming from feeding black hole-powered AGNs, not from stars. That means the population of stars in little red galaxies doesn't have to be paradigm-shatteringly high to explain their brightness.

因此，这些星系发出的大部分光可能来自黑洞提供能量的agn，而不是来自恒星。这意味着小红色星系中的恒星数量并不一定要高得惊人才能解释它们的亮度。

"This is how you solve the universe-breaking problem," team member and University of Texas at Austin scientist Anthony Taylor said.

“这就是解决宇宙破碎问题的方法，”团队成员、德克萨斯大学奥斯汀分校科学家安东尼·泰勒说。

This doesn't mean that all the questions about little red dots have been addressed, however. One mystery that persists is the absence of less redshifted galaxies resembling these little red dots in the local universe.

然而，这并不意味着所有关于小红点的问题都得到了解决。一个持续存在的谜团是，在本地宇宙中没有类似这些小红点的红移较小的星系。

One possible explanation could be the "inside-out" growth of galaxies.

一种可能的解释是星系“由内而外”的生长。

Star formation within a galaxy spreads from its heart to its outskirts. That means that as a galaxy ages, the supernova deaths of stars are depositing less and less gas in the vicinity of the central accreting supermassive black hole. This means over time, the AGN becomes less obscured by surrounding dense gas and dust. As the black hole sheds its cocoon, pushing away matter with the powerful jets of plasma it launches, the galaxy becomes brighter in bluer wavelengths and less red ones, thus losing its little red dot status.

星系内的恒星形成从中心向外围扩散。这意味着随着星系年龄的增长，超新星死亡的恒星在中心吸积超大质量黑洞附近沉积的气体越来越少。这意味着随着时间的推移，AGN被周围密集的气体和尘埃遮挡的程度会降低。当黑洞褪去它的茧，用它发射的强大的等离子射流推开物质时，星系在更蓝的波长上变得更亮，在更少的红色波长上变得更亮，从而失去了它的小红点状态。

Also supporting the idea of obscuration of AGNs as the cause of little red dots is the fact that these ancient galaxies are dim in high-energy X-ray light. This is not the case with feeding supermassive black holes closer to the Milky Way which are bright in X-rays.

这些古老的星系在高能x射线的照射下是暗淡的，这一事实也支持了agn的遮挡是小红点的原因。这不是靠近银河系的超大质量黑洞的情况，这些黑洞在x射线中是明亮的。

This could be because dense clouds of gas and dust are adept at absorbing X-rays, stunting the emission of this high-energy light. Thus, the lack of X-rays from little red dots could indicate densely-shrouded black holes.

这可能是因为稠密的气体和尘埃云擅长吸收X射线，阻碍了这种高能光的发射。因此，没有来自小红点的X射线可能表明黑洞被密集覆盖。

The team will now follow a multitude of avenues to better understand little red dot galaxies. This will include examining their sample of galaxies in mid-infrared light.

该团队现在将沿着多种途径更好地了解小红点星系。这将包括在中红外光下检查他们的星系样本。

A deeper view of little red dots and carefully selected follow-up observations could help finally solve the mystery of these challenging ancient galaxies.

对小红点的深入观察和精心挑选的后续观察可能有助于最终解开这些具有挑战性的古老星系的谜团。

"There are always two or more potential ways to explain the confounding properties of little red dots," Kocevski said. "It's a continuous exchange between models and observations, finding a balance between what aligns well between the two and what conflicts."

科切夫斯基说：“总是有两种或两种以上的可能的方法来解释小红点令人困惑的特性。”“这是模型和观察之间的持续交流，在两者之间的一致性和冲突之间找到平衡。”

The team's results were presented at the 245th meeting of the American Astronomical Society in National Harbor, Maryland, on Tuesday (Jan. 15) and have been accepted for publication in The Astrophysical Journal.

该团队的研究结果于周二（1月15日）在马里兰州国家港举行的第245届美国天文学会会议上发表，并已被《天体物理学杂志》接受发表。