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Hare BM, Scholten O, Dwyer J, Trinh TNG, Buitink S, Ter Veen S, Bonardi A, Corstanje A, Falcke H, Hörandel JR, Huege T, Mitra P, Mulrey K, Nelles A, Rachen JP, Rossetto L, Schellart P, Winchen T, Anderson J, Avruch IM, Bentum MJ, Blaauw R, Broderick JW, Brouw WN, Brüggen M, Butcher HR, Ciardi B, Fallows RA, de Geus E, Duscha S, Eislöffel J, Garrett MA, Grießmeier JM, Gunst AW, van Haarlem MP, Hessels JWT, Hoeft M, van der Horst AJ, Iacobelli M, Koopmans LVE, Krankowski A, Maat P, Norden MJ, Paas H, Pandey-Pommier M, Pandey VN, Pekal R, Pizzo R, Reich W, Rothkaehl H, Röttgering HJA, Rowlinson A, Schwarz DJ, Shulevski A, Sluman J, Smirnov O, Soida M, Tagger M, Toribio MC, van Ardenne A, Wijers RAMJ, van Weeren RJ, Wucknitz O, Zarka P, Zucca P. Needle-like structures discovered on positively charged lightning branches. Nature 2019; 568:360-363. [PMID: 30996312 DOI: 10.1038/s41586-019-1086-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/26/2019] [Indexed: 11/09/2022]
Abstract
Lightning is a dangerous yet poorly understood natural phenomenon. Lightning forms a network of plasma channels propagating away from the initiation point with both positively and negatively charged ends-called positive and negative leaders1. Negative leaders propagate in discrete steps, emitting copious radio pulses in the 30-300-megahertz frequency band2-8 that can be remotely sensed and imaged with high spatial and temporal resolution9-11. Positive leaders propagate more continuously and thus emit very little high-frequency radiation12. Radio emission from positive leaders has nevertheless been mapped13-15, and exhibits a pattern that is different from that of negative leaders11-13,16,17. Furthermore, it has been inferred that positive leaders can become transiently disconnected from negative leaders9,12,16,18-20, which may lead to current pulses that both reconnect positive leaders to negative leaders11,16,17,20-22 and cause multiple cloud-to-ground lightning events1. The disconnection process is thought to be due to negative differential resistance18, but this does not explain why the disconnections form primarily on positive leaders22, or why the current in cloud-to-ground lightning never goes to zero23. Indeed, it is still not understood how positive leaders emit radio-frequency radiation or why they behave differently from negative leaders. Here we report three-dimensional radio interferometric observations of lightning over the Netherlands with unprecedented spatiotemporal resolution. We find small plasma structures-which we call 'needles'-that are the dominant source of radio emission from the positive leaders. These structures appear to drain charge from the leader, and are probably the reason why positive leaders disconnect from negative ones, and why cloud-to-ground lightning connects to the ground multiple times.
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Affiliation(s)
- B M Hare
- KVI-Center for Advanced Radiation Technology, University of Groningen, Groningen, The Netherlands.
| | - O Scholten
- KVI-Center for Advanced Radiation Technology, University of Groningen, Groningen, The Netherlands. .,Inter University Institute for High Energies, Vrije Universiteit Brussels, Brussels, Belgium.
| | - J Dwyer
- Department of Physics and Space Science Center (EOS), University of New Hampshire, Durham, NH, USA
| | - T N G Trinh
- KVI-Center for Advanced Radiation Technology, University of Groningen, Groningen, The Netherlands
| | - S Buitink
- Astrophysical Institute, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - S Ter Veen
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - A Bonardi
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - A Corstanje
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - H Falcke
- Inter University Institute for High Energies, Vrije Universiteit Brussels, Brussels, Belgium.,ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,NIKHEF, Science Park Amsterdam, Amsterdam, The Netherlands
| | - J R Hörandel
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands.,NIKHEF, Science Park Amsterdam, Amsterdam, The Netherlands
| | - T Huege
- Astrophysical Institute, Vrije Universiteit Brussel, Brussels, Belgium.,Karlsruhe Institute of Technology (KIT), Institute for Nuclear Physics, Karlsruhe, Germany
| | - P Mitra
- Astrophysical Institute, Vrije Universiteit Brussel, Brussels, Belgium
| | - K Mulrey
- Astrophysical Institute, Vrije Universiteit Brussel, Brussels, Belgium
| | - A Nelles
- Institut für Physik, Humboldt-Universität zu Berlin, Berlin, Germany.,DESY, Zeuthen, Germany
| | - J P Rachen
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - L Rossetto
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - P Schellart
- Department of Astrophysics/IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands.,Department of Astrophysical Sciences, Princeton University, Princeton, NJ, USA
| | - T Winchen
- Astrophysical Institute, Vrije Universiteit Brussel, Brussels, Belgium
| | - J Anderson
- Institute of Geodesy and Geoinformation Science, Technical University of Berlin, Berlin, Germany.,Department 1, Geodesy GFZ German Research Centre for Geosciences, Potsdam, Germany
| | - I M Avruch
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Science and Technology, Delft, The Netherlands
| | - M J Bentum
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Eindhoven University of Technology, Eindhoven, The Netherlands
| | - R Blaauw
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - J W Broderick
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - W N Brouw
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Kapteyn Astronomical Institute, University of Groningen, Groningen, The Netherlands
| | - M Brüggen
- University of Hamburg, Hamburg, Germany
| | - H R Butcher
- Research School of Astronomy and Astrophysics, Australian National University, Canberra, Australian Capital Territory, Australia
| | - B Ciardi
- Max Planck Institute for Astrophysics, Garching, Germany
| | - R A Fallows
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - E de Geus
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,SmarterVision BV, Assen, The Netherlands
| | - S Duscha
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - J Eislöffel
- Thüringer Landessternwarte, Tautenburg, Germany
| | - M A Garrett
- Jodrell Bank Center for Astrophysics, School of Physics and Astronomy, The University of Manchester, Manchester, UK.,Leiden Observatory, Leiden University, Leiden, The Netherlands
| | - J M Grießmeier
- LPC2E-Université d'Orleans/CNRS, Orléans, France.,Station de Radioastronomie de Nancay, Observatoire de Paris, CNRS/INSU, Université d'Orleans, OSUC, Nancay, France
| | - A W Gunst
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - M P van Haarlem
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - J W T Hessels
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands
| | - M Hoeft
- Thüringer Landessternwarte, Tautenburg, Germany
| | - A J van der Horst
- Department of Physics, The George Washington University, Washington, DC, USA
| | - M Iacobelli
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - L V E Koopmans
- Kapteyn Astronomical Institute, University of Groningen, Groningen, The Netherlands
| | - A Krankowski
- University of Warmia and Mazury in Olsztyn, Space Radio-Diagnostics Research Centre, Olsztyn, Poland
| | - P Maat
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - M J Norden
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - H Paas
- Center for Information Technology (CIT), University of Groningen, Groningen, The Netherlands
| | - M Pandey-Pommier
- Station de Radioastronomie de Nancay, Observatoire de Paris, CNRS/INSU, Université d'Orleans, OSUC, Nancay, France.,CRAL, Observatoire de Lyon, Université Lyon, UMR5574, Saint Genis Laval, France
| | - V N Pandey
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Kapteyn Astronomical Institute, University of Groningen, Groningen, The Netherlands
| | - R Pekal
- Poznan Supercomputing and Networking Center (PCSS), Poznan, Poland
| | - R Pizzo
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - W Reich
- Max-Planck-Institut für Radioastronomie, Bonn, Germany
| | | | | | - A Rowlinson
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands.,Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands
| | - D J Schwarz
- Fakultät für Physik, Universität Bielefeld, Bielefeld, Germany
| | - A Shulevski
- Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands
| | - J Sluman
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - O Smirnov
- Department of Physics and Electronics, Rhodes University, Grahamstown, South Africa.,SKA South Africa, Pinelands, South Africa
| | - M Soida
- Jagiellonian University, Astronomical Observatory, Krakow, Poland
| | - M Tagger
- LPC2E-Université d'Orleans/CNRS, Orléans, France
| | - M C Toribio
- Leiden Observatory, Leiden University, Leiden, The Netherlands
| | - A van Ardenne
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
| | - R A M J Wijers
- Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands
| | - R J van Weeren
- Leiden Observatory, Leiden University, Leiden, The Netherlands
| | - O Wucknitz
- Max-Planck-Institut für Radioastronomie, Bonn, Germany
| | - P Zarka
- LESIA & USN, Observatoire de Paris, CNRS, PSL/SU/UPMC/UPD/SPC, Meudon, France
| | - P Zucca
- ASTRON, Netherlands Institute for Radio Astronomy, Dwingeloo, The Netherlands
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