Letter | Published:

A second source of repeating fast radio bursts

Naturevolume 566pages235238 (2019) | Download Citation


The discovery of a repeating fast radio burst (FRB) source1,2, FRB 121102, eliminated models involving cataclysmic events for this source. No other repeating FRB has hitherto been detected despite many recent discoveries and follow-ups3,4,5, suggesting that repeaters may be rare in the FRB population. Here we report the detection of six repeat bursts from FRB 180814.J0422+73, one of the 13 FRBs detected6 by the Canadian Hydrogen Intensity Mapping Experiment (CHIME) FRB project7 during its pre-commissioning phase in July and August 2018. These repeat bursts are consistent with its origin from a single position on the sky, with the same dispersion measure, about 189 parsecs per cubic centimetre. This line of sight traces approximately twice the expected Milky Way column density of free electrons, which implies an upper limit on the source redshift of 0.1, showing it to be closer to Earth by a factor of at least 2 than FRB 1211028. In some of the repeat bursts, we observe subpulse frequency structure, drifting and spectral variation reminiscent of that seen in FRB 1211029,10, suggesting similar emission mechanisms or propagation effects. This second repeater, found among the first few CHIME/FRB discoveries, suggests that there exists—and that CHIME/FRB and other wide-field, sensitive radio telescopes will find—a substantial population of repeating FRBs.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Data availability

The data used in this publication are available at https://chime-frb-open-data.github.io/.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.


  1. 1.

    Spitler, L. G. et al. A repeating fast radio burst. Nature 531, 202–205 (2016).

  2. 2.

    Scholz, P. et al. The repeating fast radio burst FRB 121102: multi-wavelength observations and additional bursts. Astrophys. J. 833, 177 (2016).

  3. 3.

    Caleb, M. et al. The first interferometric detections of fast radio bursts. Mon. Not. R. Astron. Soc. 468, 3746–3756 (2017).

  4. 4.

    Bhandari, S. et al. The SUrvey for Pulsars and Extragalactic Radio Bursts — II. New FRB discoveries and their follow-up. Mon. Not. R. Astron. Soc. 475, 1427–1446 (2018).

  5. 5.

    Shannon, R. M. et al. The dispersion–brightness relation for fast radio bursts from a wide-field survey. Nature 562, 386–390 (2018).

  6. 6.

    The CHIME/FRB Collaboration. Observations of fast radio bursts at frequencies down to 400 megahertz. Nature 566, https://doi.org/10.1038/s41586-018-0867-7 (2019).

  7. 7.

    The CHIME/FRB Collaboration et al. The CHIME Fast Radio Burst project: system overview. Astrophys. J. 863, 48 (2018).

  8. 8.

    Tendulkar, S. P. et al. The host galaxy and redshift of the repeating fast radio burst FRB 121102. Astrophys. J. 834, L7 (2017).

  9. 9.

    Michilli, D. et al. An extreme magneto-ionic environment associated with the fast radio burst source FRB 121102. Nature 533, 132 (2018).

  10. 10.

    Hessels, J. et al. FRB 121102 bursts show complex time-frequency structure. Astrophys. J. (submitted); preprint at http://arXiv.org/abs/1811.10748 (2019).

  11. 11.

    Ng, C. et al. CHIME FRB: an application of FFT beamforming for a radio telescope. Preprint at http://arXiv.org/abs/1702.04728 (2017).

  12. 12.

    Berger, P. et al. Holographic beam mapping of the CHIME pathfinder array in ground-based and airborne telescopes. Proc. SPIE 9906, 99060D (2016).

  13. 13.

    Gajjar, V. et al. Highest frequency detection of FRB 121102 at 4–8 GHz using the breakthrough listen digital backend at the Green Bank Telescope. Astrophys. J. 863, 2 (2018).

  14. 14.

    Farah, W. et al. FRB microstructure revealed by the real-time detection of FRB170827. Mon. Not. R. Astron. Soc. 478, 1209–1217 (2018).

  15. 15.

    Cordes, J. M. et al. Lensing of fast radio bursts by plasma structures in host galaxies. Astrophys. J. 842, 35 (2017).

  16. 16.

    Main, R. et al. Pulsar emission amplified and resolved by plasma lensing in an eclipsing binary. Nature 557, 522–525 (2018).

  17. 17.

    Bastian, T. S., Benz, A. O. & Gary, D. E. Radio emission from solar flares. Annu. Rev. Astron. Astrophys. 36, 131–188 (1998).

  18. 18.

    Cordes, J. M. & Lazio, T. J. W. NE2001. I. A new model for the galactic distribution of free electrons and its fluctuations. Preprint at http://arxiv.org/abs/astroph/0207156 (2002).

  19. 19.

    Yao, J. M., Manchester, R. N. & Wang, N. A new electron-density model for estimation of pulsar and FRB distances. Astrophys. J. 835, 29 (2017).

  20. 20.

    Avedisova, V. A catalog of star-forming regions in the galaxy. Astron. Rep. 46, 193–205 (2002).

  21. 21.

    Anderson, L. D. et al. The WISE catalog of galactic H II regions. Astrophys. J. Suppl. Ser. 212, 1 (2014).

  22. 22.

    Dolag, K., Gaensler, B. M., Beck, A. M. & Beck, M. C. Constraints on the distribution and energetics of fast radio bursts using cosmological hydrodynamic simulations. Mon. Not. R. Astron. Soc. 451, 4277–4289 (2015).

  23. 23.

    Inoue, S. Probing the cosmic reionization history and local environment of gamma-ray bursts through radio dispersion. Mon. Not. R. Astron. Soc. 348, 999–1008 (2004).

  24. 24.

    Chambers, K. C. et al. The Pan-STARRS1 surveys. Preprint at http://arXiv.org/abs/1612.05560 (2016).

  25. 25.

    Myers, S. T., Baum, S. A. & Chandler, C. J. The Karl G. Jansky Very Large Array Sky Survey (VLASS). Am. Astron. Soc. Meet. Abstr. 223, 236.01 (2014).

  26. 26.

    Condon, J. J. et al. The NRAO VLA Sky Survey. Astrophys. J. 115, 1693–1716 (1998).

  27. 27.

    Petroff, E. et al. A survey of FRB fields: limits on repeatability. Mon. Not. R. Astron. Soc. 454, 457–462 (2015).

  28. 28.

    Connor, L. & Petroff, E. On detecting repetition from fast radio bursts. Astrophys. J. 861, L1 (2018).

  29. 29.

    Perley, R. A. & Butler, B. J. An accurate flux density scale from 50 MHz to 50 GHz. Astrophys. J. Suppl. Ser. 230, 7 (2017).

  30. 30.

    Obrocka, M., Stappers, B. & Wilkinson, P. Localising fast radio bursts and other transients using interferometric arrays. Astron. Astrophys. 579, A69 (2015).

  31. 31.

    Petroff, E. et al. A fast radio burst with a low dispersion measure. Mon. Not. R. Astron. Soc. 482, 3109–3115 (2019).

  32. 32.

    Ng, C. & CHIME/Pulsar Collaboration. Pulsar science with the CHIME telescope in pulsar astrophysics. In Proc. IAU Symp. 337, Pulsar Astrophysics—The Next 50 Years (eds Weltevrede, P., Perera, B. B. P., Levin Preston, L. & Sanidas, S.) 179–182 (Cambridge Univ. Press, Cambridge, 2017).

  33. 33.

    Ransom, S. PRESTO: PulsaR Exploration and Search TOolkit. http://www.ascl.net/1107.017 (ascl:1107.017, Astrophysics Source Code Library, 2011).

  34. 34.

    Manchester, R. N., Hobbs, G. B., Teoh, A. & Hobbs, M. The Australia Telescope National Facility Pulsar Catalogue. Astron. J. 129, 1993–2006 (2005).

  35. 35.

    Stovall, K. et al. The Green Bank Northern Celestial Cap Pulsar Survey. I. Survey description, data analysis, and initial results. Astrophys. J. 791, 67 (2014).

  36. 36.

    Farrow, D. J. et al. Pan-STARRS1: Galaxy clustering in the Small Area Survey 2. Mon. Not. R. Astron. Soc. 437, 748–770 (2014).

  37. 37.

    Intema, H. T., Jagannathan, P., Mooley, K. P. & Frail, D. A. The GMRT 150 MHz all-sky radio survey. First alternative data release TGSS ADR1. Astron. Astrophys. 598, A78 (2017).

Download references


We are grateful for the warm reception and skilful help we have received from the Dominion Radio Astrophysical Observatory, operated by the National Research Council Canada. The CHIME/FRB Project is funded by a grant from the Canada Foundation for Innovation 2015 Innovation Fund (Project 33213), as well as by the Provinces of British Columbia and Québec, and by the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto. Additional support was provided by the Canadian Institute for Advanced Research (CIFAR), McGill University and the McGill Space Institute via the Trottier Family Foundation, and the University of British Columbia. The Dunlap Institute is funded by an endowment established by the David Dunlap family and the University of Toronto. Research at Perimeter Institute is supported by the Government of Canada through Industry Canada and by the Province of Ontario through the Ministry of Research & Innovation. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. P.C. is supported by an FRQNT Doctoral Research Award and a Mitacs Globalink Graduate Fellowship. M.D. acknowledges support from CIFAR, Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery and Accelerator Grants, and from FRQNT Centre de Recherche en Astrophysique du Québec (CRAQ). B.M.G. acknowledges the support of the NSERC through grant RGPIN-2015-05948, and the Canada Research Chairs programme. A.S.H. is partly supported by the Dunlap Institute. V.M.K. holds the Lorne Trottier Chair in Astrophysics & Cosmology and a Canada Research Chair and receives support from an NSERC Discovery Grant and Herzberg Award, from an R. Howard Webster Foundation Fellowship from CIFAR, and CRAQ. C.M. is supported by a NSERC Undergraduate Research Award. J.M.-P. is supported by the MIT Kavli Fellowship in Astrophysics and a FRQNT postdoctoral research scholarship. M.M. is supported by a NSERC Canada Graduate Scholarship. Z.P. is supported by a Schulich Graduate Fellowship. S.M.R. is a CIFAR Senior Fellow and is supported by the NSF Physics Frontiers Center award 1430284. P.S. is supported by a DRAO Covington Fellowship from the National Research Council Canada. FRB research at UBC is supported by an NSERC Discovery Grant and by CIFAR.

Reviewer information

Nature thanks G. Hallinan and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Competing interests

The authors declare no competing interests.

Author information

Author notes

  1. A list of participants and their affiliations appears at the end of the paper.


  1. Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada

    • M. Amiri
    • , D. Cubranic
    • , M. Deng
    • , M. Fandino
    • , D. C. Good
    • , M. Halpern
    • , A. S. Hill
    • , G. Hinshaw
    • , C. Höfer
    • , N. Milutinovic
    • , T. Pinsonneault-Marotte
    • , J. R. Shaw
    • , I. H. Stairs
    •  & P. Yadav
  2. CSEE, West Virginia University, Morgantown, WV, USA

    • K. Bandura
  3. Center for Gravitational Waves and Cosmology, West Virginia University, Morgantown, WV, USA

    • K. Bandura
  4. Department of Physics, McGill University, Montréal, Québec, Canada

    • M. Bhardwaj
    • , P. Boubel
    • , P. J. Boyle
    • , C. Brar
    • , P. Chawla
    • , J. F. Cliche
    • , M. Dobbs
    • , E. Fonseca
    • , A. J. Gilbert
    • , D. S. Hanna
    • , A. Josephy
    • , V. M. Kaspi
    • , J. Mena-Parra
    • , M. Merryfield
    • , D. Michilli
    • , C. Moatti
    • , A. Naidu
    • , C. Patel
    • , Z. Pleunis
    • , S. R. Siegel
    •  & S. P. Tendulkar
  5. McGill Space Institute, McGill University, Montréal, Québec, Canada

    • M. Bhardwaj
    • , P. Boubel
    • , P. J. Boyle
    • , C. Brar
    • , P. Chawla
    • , J. F. Cliche
    • , M. Dobbs
    • , E. Fonseca
    • , A. J. Gilbert
    • , D. S. Hanna
    • , A. Josephy
    • , V. M. Kaspi
    • , J. Mena-Parra
    • , M. Merryfield
    • , D. Michilli
    • , C. Moatti
    • , A. Naidu
    • , C. Patel
    • , Z. Pleunis
    • , S. R. Siegel
    •  & S. P. Tendulkar
  6. Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba, Canada

    • M. M. Boyce
  7. Harvard University, Cambridge, MA, USA

    • M. Burhanpurkar
  8. Department of Astronomy and Astrophysics, University of Toronto, Toronto, Ontario, Canada

    • T. Cassanelli
    • , N. Denman
    • , B. M. Gaensler
    • , A. Gill
    • , R. Mckinven
    • , I. Tretyakov
    •  & K. Vanderlinde
  9. Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, Ontario, Canada

    • T. Cassanelli
    • , N. Denman
    • , B. M. Gaensler
    • , A. Gill
    • , R. Mckinven
    • , C. Ng
    • , M. Rahman
    • , A. Renard
    •  & K. Vanderlinde
  10. Perimeter Institute for Theoretical Physics, Waterloo, Ontario, Canada

    • U. Giri
    • , D. A. Lang
    • , M. Rafiei-Ravandi
    •  & K. M. Smith
  11. Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario, Canada

    • U. Giri
    •  & D. A. Lang
  12. Dominion Radio Astrophysical Observatory, Herzberg Astronomy and Astrophysics Research Centre, National Research Council Canada, Penticton, British Columbia, Canada

    • A. S. Hill
    • , T. L. Landecker
    • , N. Milutinovic
    • , P. Scholz
    •  & J. R. Shaw
  13. Space Science Institute, Boulder, CO, USA

    • A. S. Hill
  14. Canadian Institute for Theoretical Astrophysics, Toronto, Ontario, Canada

    • H.-H. Lin
    •  & U. Pen
  15. MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA

    • K. W. Masui
    •  & J. Mena-Parra
  16. Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA

    • K. W. Masui
  17. Department of Physics, Yale University, New Haven, CT, USA

    • L. B. Newburgh
  18. National Radio Astronomy Observatory, Charlottesville, VA, USA

    • S. M. Ransom
  19. Department of Physics, University of Toronto, Toronto, Ontario, Canada

    • I. Tretyakov


  1. The CHIME/FRB Collaboration


All authors on this paper played either leadership or significant supporting roles in one or more of the following: the management, development and construction of the CHIME telescope, the CHIME/FRB instrument and the CHIME/FRB software data pipeline, the commissioning and operations of the CHIME/FRB instrument, the data analysis and preparation of this manuscript.

Corresponding author

Correspondence to C. Ng.

Extended data figures and tables

  1. Extended Data Fig. 1 Subpulse frequency drift rates.

    a, b, Subpulse model fits for the 17 September CHIME/FRB burst (a) and the 28 October CHIME/Pulsar burst (b). Left to right, the lower subpanel shows dedispersed intensity data (DM = 189.4 pc cm−3), the best-fit model and residuals, and the upper subpanel shows the summed time series. Only the half of the receiver bandwidth in which the burst was detected is used in the analysis. The colour scale for the intensity data and residuals is clipped to ±3σ from the median of the residual data and a divergent rather than a sequential colour scale is used for the residuals to guide the eye. Red points overlaid on the models show the centre frequency and 1σ statistical uncertainty with a 10-MHz systematic error added in quadrature. The red dashed lines show linear drift rates of −6.4 MHz ms−1 (a) and −1.3 MHz ms−1 (b).

  2. Extended Data Table 1 Subpulse parameters

About this article

Publication history




Issue Date



Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.