Letter | Published:

An ultraluminous quasar with a twelve-billion-solar-mass black hole at redshift 6.30

Nature volume 518, pages 512515 (26 February 2015) | Download Citation



So far, roughly 40 quasars with redshifts greater than z = 6 have been discovered1,2,3,4,5,6,7,8. Each quasar contains a black hole with a mass of about one billion solar masses (109 )2,6,7,9,10,11,12,13. The existence of such black holes when the Universe was less than one billion years old presents substantial challenges to theories of the formation and growth of black holes and the coevolution of black holes and galaxies14. Here we report the discovery of an ultraluminous quasar, SDSS J010013.02+280225.8, at redshift z = 6.30. It has an optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars. On the basis of the deep absorption trough15 on the blue side of the Lyman-α emission line in the spectrum, we estimate the proper size of the ionized proximity zone associated with the quasar to be about 26 million light years, larger than found with other z > 6.1 quasars with lower luminosities16. We estimate (on the basis of a near-infrared spectrum) that the black hole has a mass of 1.2 × 1010 , which is consistent with the 1.3 × 1010 derived by assuming an Eddington-limited accretion rate.

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X.-B.W. thanks the NSFC (grant nos 11033001 and 11373008), the Strategic Priority Research Program ‘The Emergence of Cosmological Structures’ of the Chinese Academy of Sciences (grant no. XDB09000000), and the National Key Basic Research Program of China (grant no. 2014CB845700) for support. X.F., R.W. and I.D.M. thank the US NSF (grant nos AST 08-06861 and AST 11-07682) for support. R.W. thanks the NSFC (grant no. 11443002) for support. We acknowledge the support of the staff of the Lijiang 2.4-m telescope. Funding for the telescope was provided by the Chinese Academy of Sciences and the People’s Government of Yunnan Province. This research uses data obtained through the Telescope Access Program (TAP), which has been funded by the Strategic Priority Research Program ‘The Emergence of Cosmological Structures’ (grant no. XDB09000000), National Astronomical Observatories, Chinese Academy of Sciences, and the Special Fund for Astronomy from the Ministry of Finance of China. We thank D. Osip for help with Magellan/FIRE spectroscopy, and Y.-L. Ai, L. C. Ho, Y. Shen and J.-G. Wang for suggestions about data analyses. We acknowledge the use of SDSS, 2MASS and WISE data, and of the MMT, LBT, Gemini and Magellan telescopes; detailed acknowledgments of these facilities can be found in Supplementary Information.

Author information


  1. Department of Astronomy, School of Physics, Peking University, Beijing 100871, China

    • Xue-Bing Wu
    • , Feige Wang
    • , Jinyi Yang
    •  & Qian Yang
  2. Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China

    • Xue-Bing Wu
    • , Feige Wang
    • , Xiaohui Fan
    • , Linhua Jiang
    • , Ran Wang
    • , Jinyi Yang
    •  & Qian Yang
  3. Steward Observatory, University of Arizona, Tucson, Arizona 85721-0065, USA

    • Xiaohui Fan
    •  & Ian D. McGreer
  4. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011, China

    • Weimin Yi
  5. University of Chinese Academy of Sciences, Beijing 100049, China

    • Weimin Yi
  6. Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, China

    • Weimin Yi
  7. Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 200030, China

    • Wenwen Zuo
  8. Mount Stromlo Observatory, Research School of Astronomy and Astrophysics, Australian National University, Weston Creek, Australian Capital Territory 2611, Australia

    • Fuyan Bian
  9. Large Binocular Telescope Observatory, University of Arizona, Tucson, Arizona 85721, USA

    • David Thompson
  10. Las Campanas Observatory, Carnegie Institution of Washington, Colina el Pino, Casilla 601, La Serena, Chile

    • Yuri Beletsky


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X.-B.W., F.W. and X.F. planned the study, and wrote the draft version of the paper. All other co-authors contributed extensively and equally to the observations, data analyses and writing of the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Xue-Bing Wu.

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