维基百科

ULAS J1342+0928

ULAS J1342+0928为已知距离第二遥远的的类星体，位于牧夫座[3]，其中心也是已知最古老和最遥远的超大质量黑洞之一[1][5][6][7]。其红移为z=7.54，超越之前被认为是最遥远的类星体ULAS J1120+0641（红移为z=7）[1]，并且一直为最遥远的类星体，直至2020年3月才被PSO J0309+27的133亿光年的纪录打破。相关报导中指出[谁？]，其中心的超大质量黑洞的质量是太阳质量的8亿倍[5]。

ULAS J1342+0928[1][2]
艺术家概念下相似的类星体。
观测资料(历元 J2000.0)
星座牧夫座[3]
赤经13h 42m 08.10s
赤纬+09° 28′ 38.61″
红移7.54[1]
距离29.36 Gly（9.00 Gpc）
（同移距离）[4]
13.1 Gly（4.0 Gpc）
（光程距离）[5]
其他编号
ULAS J134208.10+092838.61,[1] Quasar20171206[6]
参见：类星体，类星体列表

发现 编辑

2017年12月6日[1]，天文学家发表文章表示[谁？]，他们使用广域红外线巡天探测卫星[6]的资料，结合位在智利拉斯坎帕纳斯天文台的麦哲伦望远镜、亚利桑那州的大双筒望远镜和夏威夷的双子北望远镜的观测资料，当宇宙大约6.9亿岁时，类星体与相关的黑洞就存在了（大约宇宙年龄的5%，目前已知的宇宙年龄为138亿岁）[1]。

这个类星体来自宇宙在黑暗时代崭露头角之后，被称为再电离的时代[5]。大量的气体和尘埃被检测到从类星体释放进入宿主星系成为星际物质[2]。

描述 编辑

ULAS J1342+0928被测量出7.54的红移，这相当于距离地球294.6亿光年的同移距离[1][4]。截至2017年12月 (2017-12)，于当时为止观测到距离最遥远的类星体。在地球观察到这个类星体辐射的光是在大爆炸之后不到6.9亿年，也就是大约在131亿年前辐射出来的[5][8]。

估计这个类星体光度是4×1013 太阳光度[1]。估计输出这些能量的超大质量黑洞拥有8×108太阳质量[1]。根据天文学家爱德华多·巴尼亚多斯（Eduardo Bañados）的资料[9]，这个特殊的类星体是如此的明亮，它将成为后续研究的一个金矿，是研究早期宇宙的一个关键实验室[5]。

重要性 编辑

来自ULAS J1342+0928的光是理论预测星际物质从结束电中性成为电离状态的过渡时期（再电离时期）。类星体在这个过程中可能是一个重要的能量来源，这标志着黑暗时期，也就是宇宙的黑暗时代的终结。所以，观察来自黑暗时期的过渡时期的类星体是理论学家主要的兴趣所在[10][11]。由于它们的高紫外线光度，类星体也是研究再电离过程的最好来源。这一发现也被描述为对黑洞形成理论具有挑战性：通过在宇宙早期阶段拥有一个比预期大得多的超大质量黑洞[6]。然而，这并不是第一个能提供这样挑战的遥远类星体 [12][13]。

少数的来源质疑[谁？]，如此大质量的超大质量黑洞（如ULAS J1342+0928）很难解释在大爆炸之后极短的时间内快速生成[6]，可能证明我们的宇宙是大反弹的结果，而非大爆炸；是在大反弹之前形成这些超大质量黑洞[14][15]。

相关条目 编辑

参考资料 编辑

  1. ^ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 Bañados, Eduardo; et al. An 800-million-solar-mass black hole in a significantly neutral Universe at a redshift of 7.5. Nature. 6 December 2017 [6 December 2017]. Bibcode:2018Natur.553..473B. arXiv:1712.01860  . doi:10.1038/nature25180. （原始内容存档于2019-08-30）. 
  2. ^ 2.0 2.1 Venemans, Bram P.; et al. Copious Amounts of Dust and Gas in a z = 7.5 Quasar Host Galaxy. The Astrophysical Journal Letters. 6 December 2017, 851 (1) [6 December 2017]. 
  3. ^ 3.0 3.1 Staff. Finding the constellation which contains given sky coordinates. djm.com. [6 December 2017]. （原始内容存档于2019-08-15）. 
  4. ^ 4.0 4.1 Wright, Ned. Ned Wright's Javascript Cosmology Calculator. UCLA. 24 April 2016 [7 December 2017]. （原始内容存档于2018-09-29）. 
  5. ^ 5.0 5.1 5.2 5.3 5.4 5.5 Choi, Charles Q. Oldest Monster Black Hole Ever Found Is 800 Million Times More Massive Than the Sun. Space.com. 6 December 2017 [6 December 2017]. （原始内容存档于2017-12-06）. 
  6. ^ 6.0 6.1 6.2 6.3 6.4 Landau, Elizabeth; Bañados, Eduardo. Found: Most Distant Black Hole. NASA. 6 December 2017 [6 December 2017]. （原始内容存档于2019-02-18）. "This black hole grew far larger than we expected in only 690 million years after the Big Bang, which challenges our theories about how black holes form," said study co-author Daniel Stern of NASA's Jet Propulsion Laboratory in Pasadena, California. 
  7. ^ Decarli, Roberto; et al. Rest-frame optical photometry of a z-7.54 quasar and its environment. CalTech. September 2017 [6 December 2017]. （原始内容存档于2017-12-07）. 
  8. ^ Grush, Loren. The most distant supermassive black hole ever found holds secrets to the early Universe - We’re seeing how it looked when the Universe was a toddler. TheVerge. 6 December 2017 [6 December 2017]. （原始内容存档于2017-12-10）. 
  9. ^ Bañados, Eduardo. Eduardo Bañados - Bio/CV. Carnegie Institution for Science. 2017 [7 December 2017]. （原始内容存档于2019-02-03）. 
  10. ^ Matson, John. Brilliant, but Distant: Most Far-Flung Known Quasar Offers Glimpse into Early Universe. Scientific American. 29 June 2011 [7 December 2017]. （原始内容存档于2013-11-03）. 
  11. ^ Willott, C. Cosmology: A monster in the early Universe. Nature. 2011, 474 (7353): 583–584. Bibcode:2011Natur.474..583W. PMID 21720357. arXiv:1106.6090  . doi:10.1038/474583a. preprint of this paper （页面存档备份，存于互联网档案馆）
  12. ^ Davide Castelvecchi. Young black hole had monstrous growth spurt. Nature. 25 February 2015 [9 December 2017]. （原始内容存档于2021-05-27）. A black hole that grew to gargantuan size in the Universe's first billion years is by far the largest yet spotted from such an early date, researchers have announced. The object, discovered by astronomers in 2013, is 12 billion times as massive as the Sun, and six times greater than its largest-known contemporaries. Its existence poses a challenge for theories of the evolution of black holes, stars and galaxies, astronomers say. Light from the black hole took 12.9 billion years to reach Earth, so astronomers see the object as it was 900 million years after the Big Bang. That “is actually a very short time” for a black hole to have grown so large, says astronomer Xue-Bing Wu of Peking University in Beijing. 
  13. ^ Discovery in the early universe poses black hole growth puzzle. Phys.org. 11 May 2015 [9 December 2017]. （原始内容存档于2017-12-09）. Now, researchers from the Max Planck Institute for Astronomy (MPIA) have discovered three quasars that challenge conventional wisdom on black hole growth. These quasars are extremely massive, but should not have had sufficient time to collect all that mass. The astronomers observed quasars whose light took nearly 13 billion years to reach Earth. In consequence, the observations show these quasars not as they are today, but as they were almost 13 billion years ago, less than a billion years after the big bang. The quasars in question have about a billion times the mass of the sun. All current theories of black hole growth postulate that, in order to grow that massive, the black holes would have needed to collect infalling matter, and shine brightly as quasars, for at least a hundred million years. But these three quasars proved to be have been active for a much shorter time, less than 100,000 years. "This is a surprising result," explains Christina Eilers, a doctoral student at MPIA and lead author of the present study. "We don't understand how these young quasars could have grown the supermassive black holes that power them in such a short time." 
  14. ^ Jamie Seidel. Black hole at the dawn of time challenges our understanding of how the universe was formed. News Corp Australia. 7 December 2017 [9 December 2017]. （原始内容存档于2017-12-09）. It had reached its size just 690 million years after the point beyond which there is nothing. The most dominant scientific theory of recent years describes that point as the Big Bang — a spontaneous eruption of reality as we know it out of a quantum singularity. But another idea has recently been gaining weight: that the universe goes through periodic expansions and contractions — resulting in a “Big Bounce”. And the existence of early black holes has been predicted to be a key telltale as to whether or not the idea may be valid. This one is very big. To get to its size — 800 million times more mass than our Sun — it must have swallowed a lot of stuff. ... As far as we understand it, the universe simply wasn’t old enough at that time to generate such a monster. 
  15. ^ Youmagazine staff. A Black Hole that is more ancient than the Universe. You Magazine (Greece). 8 December 2017 [9 December 2017]. （原始内容存档于2021-06-14） （希腊语）. This new theory that accepts that the Universe is going through periodic expansions and contractions is called "Big Bounce" 

外部链接 编辑

纪录
前任者：
ULAS J1120+0641 		已知最遥远的类星体
2017 –2021  		继任者：
QSO J0313−1806

天球赤道座标：  13h 42m 08.10s，+09° 28′ 38.61″

取自“https://zh.wikipedia.org/w/index.php?title=ULAS_J1342%2B0928&oldid=82247505”