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Chitta LP, Zhukov AN, Berghmans D, Peter H, Parenti S, Mandal S, Aznar Cuadrado R, Schühle U, Teriaca L, Auchère F, Barczynski K, Buchlin É, Harra L, Kraaikamp E, Long DM, Rodriguez L, Schwanitz C, Smith PJ, Verbeeck C, Seaton DB. Picoflare jets power the solar wind emerging from a coronal hole on the Sun. Science 2023; 381:867-872. [PMID: 37616348 DOI: 10.1126/science.ade5801] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 07/14/2023] [Indexed: 08/26/2023]
Abstract
Coronal holes are areas on the Sun with open magnetic field lines. They are a source region of the solar wind, but how the wind emerges from coronal holes is not known. We observed a coronal hole using the Extreme Ultraviolet Imager on the Solar Orbiter spacecraft. We identified jets on scales of a few hundred kilometers, which last 20 to 100 seconds and reach speeds of ~100 kilometers per second. The jets are powered by magnetic reconnection and have kinetic energy in the picoflare range. They are intermittent but widespread within the observed coronal hole. We suggest that such picoflare jets could produce enough high-temperature plasma to sustain the solar wind and that the wind emerges from coronal holes as a highly intermittent outflow at small scales.
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Affiliation(s)
- L P Chitta
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - A N Zhukov
- Solar-Terrestrial Centre of Excellence, Solar Influences Data Analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
- Skobeltsyn Institute of Nuclear Physics, Moscow State University, Moscow 119991, Russia
| | - D Berghmans
- Solar-Terrestrial Centre of Excellence, Solar Influences Data Analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
| | - H Peter
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - S Parenti
- Institut d'Astrophysique Spatiale, Centre National de la Recherche Scientifique, Université Paris-Saclay, 91405 Orsay, France
| | - S Mandal
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - R Aznar Cuadrado
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - U Schühle
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - L Teriaca
- Max-Planck-Institut für Sonnensystemforschung, 37077 Göttingen, Germany
| | - F Auchère
- Institut d'Astrophysique Spatiale, Centre National de la Recherche Scientifique, Université Paris-Saclay, 91405 Orsay, France
| | - K Barczynski
- Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, 7260 Davos Dorf, Switzerland
- Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - É Buchlin
- Institut d'Astrophysique Spatiale, Centre National de la Recherche Scientifique, Université Paris-Saclay, 91405 Orsay, France
| | - L Harra
- Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, 7260 Davos Dorf, Switzerland
- Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - E Kraaikamp
- Solar-Terrestrial Centre of Excellence, Solar Influences Data Analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
| | - D M Long
- Mullard Space Science Laboratory, University College London, Dorking, Surrey RH5 6NT, UK
- Astrophysics Research Centre, School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland, UK
| | - L Rodriguez
- Solar-Terrestrial Centre of Excellence, Solar Influences Data Analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
| | - C Schwanitz
- Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, 7260 Davos Dorf, Switzerland
- Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
| | - P J Smith
- Mullard Space Science Laboratory, University College London, Dorking, Surrey RH5 6NT, UK
| | - C Verbeeck
- Solar-Terrestrial Centre of Excellence, Solar Influences Data Analysis Centre, Royal Observatory of Belgium, 1180 Brussels, Belgium
| | - D B Seaton
- Southwest Research Institute, Boulder, CO 80302, USA
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Shen Y. Observation and modelling of solar jets. Proc Math Phys Eng Sci 2021; 477:20200217. [PMID: 35153538 PMCID: PMC8317983 DOI: 10.1098/rspa.2020.0217] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 01/12/2021] [Indexed: 11/27/2022] Open
Abstract
The solar atmosphere is full of complicated transients manifesting the reconfiguration of the solar magnetic field and plasma. Solar jets represent collimated, beam-like plasma ejections; they are ubiquitous in the solar atmosphere and important for our understanding of solar activities at different scales, the magnetic reconnection process, particle acceleration, coronal heating, solar wind acceleration, as well as other related phenomena. Recent high-spatio-temporal-resolution, wide-temperature coverage and spectroscopic and stereoscopic observations taken by ground-based and space-borne solar telescopes have revealed many valuable new clues to restrict the development of theoretical models. This review aims at providing the reader with the main observational characteristics of solar jets, physical interpretations and models, as well as unsolved outstanding questions in future studies.
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Affiliation(s)
- Yuandeng Shen
- Yunnan Observatories, Chinese Academy of Sciences, Kunming 650216, People’s Republic of China
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Samanta T, Tian H, Nakariakov VM. Evidence for Vortex Shedding in the Sun's Hot Corona. PHYSICAL REVIEW LETTERS 2019; 123:035102. [PMID: 31386484 DOI: 10.1103/physrevlett.123.035102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 06/21/2019] [Indexed: 06/10/2023]
Abstract
Vortex shedding is an oscillating flow that is commonly observed in fluids due to the presence of a blunt body in a flowing medium. Numerical simulations have shown that the phenomenon of vortex shedding could also develop in the magnetohydrodynamic (MHD) domain. The dimensionless Strouhal number, the ratio of the blunt body diameter to the product of the period of vortex shedding and the speed of a flowing medium, is a robust indicator for vortex shedding, and, generally of the order of 0.2 for a wide range of Reynolds number. Using an observation from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we report a wavelike or oscillating plasma flow propagating upward against the Sun's gravitational force. A newly formed shrinking loop in the postflare region possibly generates the oscillation of the upflow in the wake of the hot and dense loop through vortex shedding. The computed Strouhal number is consistent with the prediction from previous MHD simulations. Our observation suggests the possibility of vortex shedding in the solar corona.
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Affiliation(s)
- Tanmoy Samanta
- School of Earth and Space Sciences, Peking University, Beijing 100871, China
| | - Hui Tian
- School of Earth and Space Sciences, Peking University, Beijing 100871, China
| | - Valery M Nakariakov
- Centre for Fusion, Space and Astrophysics, University of Warwick, Coventry CV47AL, United Kingdom
- St. Petersburg Branch, Special Astrophysical Observatory, Russian Academy of Sciences, 196140 St. Petersburg, Russia
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