Articles | Volume 39, issue 3
https://doi.org/10.5194/angeo-39-379-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-39-379-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
05 May 2021
Regular paper |
| 05 May 2021
| 05 May 2021
Warm protons at comet 67P/Churyumov–Gerasimenko – implications for the infant bow shock
European Space Research and Technology Centre, European Space Agency, Keplerlaan 1, 2201AZ Noordwijk, the Netherlands
Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany
Herbert Gunell
Department of Physics, Umeå University, 901 87 Umeå, Sweden
Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Avenue Circulaire 3, 1180 Brussels, Belgium
Fredrik Johansson
Institutet för rymdfysik, Lägerhyddsvägen 1, 752 37 Uppsala, Sweden
Kristie LLera
Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238-5166, USA
Hans Nilsson
Institutet för rymdfysik, Rymdcampus 1, Kiruna, Sweden
Karl-Heinz Glassmeier
Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Mendelssohnstr. 3, 38106 Braunschweig, Germany
Matthew G. G. T. Taylor
European Space Research and Technology Centre, European Space Agency, Keplerlaan 1, 2201AZ Noordwijk, the Netherlands
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Ariel Tello Fallau, Charlotte Goetz, Cyril Simon Wedlund, Martin Volwerk, and Anja Moeslinger
Ann. Geophys., 41, 569–587, https://doi.org/10.5194/angeo-41-569-2023, https://doi.org/10.5194/angeo-41-569-2023, 2023
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The plasma environment of comet 67P provides a unique laboratory to study plasma phenomena in the solar system. Previous studies have reported the existence of mirror modes at 67P but no further systematic investigation has so far been done. This study aims to learn more about these waves. We investigate the magnetic field measured by Rosetta and find 565 mirror mode signatures. The detected mirror modes are likely generated upstream of the observation and have been modified by the plasma.
Katharina Ostaszewski, Karl-Heinz Glassmeier, Charlotte Goetz, Philip Heinisch, Pierre Henri, Sang A. Park, Hendrik Ranocha, Ingo Richter, Martin Rubin, and Bruce Tsurutani
Ann. Geophys., 39, 721–742, https://doi.org/10.5194/angeo-39-721-2021, https://doi.org/10.5194/angeo-39-721-2021, 2021
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Plasma waves are an integral part of cometary physics, as they facilitate the transfer of energy and momentum. From intermediate to strong activity, nonlinear asymmetric plasma and magnetic field enhancements dominate the inner coma of 67P/CG. We present a statistical survey of these structures from December 2014 to June 2016, facilitated by Rosetta's unprecedented long mission duration. Using a 1D MHD model, we show they can be described as a combination of nonlinear and dissipative effects.
Martin Volwerk, David Mautner, Cyril Simon Wedlund, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Schmid, Diana Rojas-Castillo, Owen W. Roberts, and Ali Varsani
Ann. Geophys., 39, 239–253, https://doi.org/10.5194/angeo-39-239-2021, https://doi.org/10.5194/angeo-39-239-2021, 2021
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The magnetic field in the solar wind is not constant but varies in direction and strength. One of these variations shows a strong local reduction of the magnetic field strength and is called a magnetic hole. These holes are usually an indication that there is, or has been, a temperature difference in the plasma of the solar wind, with the temperature along the magnetic field lower than perpendicular. The MMS spacecraft data have been used to study the characteristics of these holes near Earth.
Herbert Gunell, Charlotte Goetz, Elias Odelstad, Arnaud Beth, Maria Hamrin, Pierre Henri, Fredrik L. Johansson, Hans Nilsson, and Gabriella Stenberg Wieser
Ann. Geophys., 39, 53–68, https://doi.org/10.5194/angeo-39-53-2021, https://doi.org/10.5194/angeo-39-53-2021, 2021
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When the magnetised solar wind meets the plasma surrounding a comet, the magnetic field is enhanced in front of the comet, and the field lines are draped around it. This happens because electric currents are induced in the plasma. When these currents flow through the plasma, they can generate waves. In this article we present observations of ion acoustic waves, which is a kind of sound wave in the plasma, detected by instruments on the Rosetta spacecraft near comet 67P/Churyumov–Gerasimenko.
Martin Volwerk, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Heyner, and Brian Anderson
Ann. Geophys., 38, 51–60, https://doi.org/10.5194/angeo-38-51-2020, https://doi.org/10.5194/angeo-38-51-2020, 2020
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The magnetic field that is carried by the solar wind slowly decreases in strength as it moves further from the Sun. However, there are sometimes localized decreases in the magnetic field strength, called magnetic holes. These are small structures where the magnetic field strength decreases to less than 50 % of the surroundings and the plasma density increases. This paper presents a statistical study of the behaviour of these holes between Mercury and Venus using MESSENGER data.
Ingo Richter, Hans-Ulrich Auster, Gerhard Berghofer, Chris Carr, Emanuele Cupido, Karl-Heinz Fornaçon, Charlotte Goetz, Philip Heinisch, Christoph Koenders, Bernd Stoll, Bruce T. Tsurutani, Claire Vallat, Martin Volwerk, and Karl-Heinz Glassmeier
Ann. Geophys., 34, 609–622, https://doi.org/10.5194/angeo-34-609-2016, https://doi.org/10.5194/angeo-34-609-2016, 2016
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We have analysed the magnetic field measurements performed on the ROSETTA orbiter and the lander PHILAE during PHILAE's descent to comet 67P/Churyumov-Gerasimenko on 12 November 2014. We observed a new type of low-frequency wave with amplitudes of ~ 3 nT, frequencies of 20–50 mHz, wavelengths of ~ 300 km, and propagation velocities of ~ 6 km s−1. The waves are generated in a ~ 100 km region around the comet a show a highly correlated behaviour, which could only be determined by two-point observations.
M. Volwerk, I. Richter, B. Tsurutani, C. Götz, K. Altwegg, T. Broiles, J. Burch, C. Carr, E. Cupido, M. Delva, M. Dósa, N. J. T. Edberg, A. Eriksson, P. Henri, C. Koenders, J.-P. Lebreton, K. E. Mandt, H. Nilsson, A. Opitz, M. Rubin, K. Schwingenschuh, G. Stenberg Wieser, K. Szegö, C. Vallat, X. Vallieres, and K.-H. Glassmeier
Ann. Geophys., 34, 1–15, https://doi.org/10.5194/angeo-34-1-2016, https://doi.org/10.5194/angeo-34-1-2016, 2016
Short summary
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The solar wind magnetic field drapes around the active nucleus of comet 67P/CG, creating a magnetosphere. The solar wind density increases and with that the pressure, which compresses the magnetosphere, increasing the magnetic field strength near Rosetta. The higher solar wind density also creates more ionization through collisions with the gas from the comet. The new ions are picked-up by the magnetic field and generate mirror-mode waves, creating low-field high-density "bottles" near 67P/CG.
I. Richter, C. Koenders, H.-U. Auster, D. Frühauff, C. Götz, P. Heinisch, C. Perschke, U. Motschmann, B. Stoll, K. Altwegg, J. Burch, C. Carr, E. Cupido, A. Eriksson, P. Henri, R. Goldstein, J.-P. Lebreton, P. Mokashi, Z. Nemeth, H. Nilsson, M. Rubin, K. Szegö, B. T. Tsurutani, C. Vallat, M. Volwerk, and K.-H. Glassmeier
Ann. Geophys., 33, 1031–1036, https://doi.org/10.5194/angeo-33-1031-2015, https://doi.org/10.5194/angeo-33-1031-2015, 2015
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We present a first report on magnetic field measurements made in the coma of comet 67P/C-G in its low-activity state. The plasma environment is dominated by quasi-coherent, large-amplitude, compressional magnetic field oscillations around 40mHz, differing from the observations at strongly active comets where waves at the cometary ion gyro-frequencies are the main feature. We propose a cross-field current instability associated with the newborn cometary ions as a possible source mechanism.
Ariel Tello Fallau, Charlotte Goetz, Cyril Simon Wedlund, Martin Volwerk, and Anja Moeslinger
Ann. Geophys., 41, 569–587, https://doi.org/10.5194/angeo-41-569-2023, https://doi.org/10.5194/angeo-41-569-2023, 2023
Short summary
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The plasma environment of comet 67P provides a unique laboratory to study plasma phenomena in the solar system. Previous studies have reported the existence of mirror modes at 67P but no further systematic investigation has so far been done. This study aims to learn more about these waves. We investigate the magnetic field measured by Rosetta and find 565 mirror mode signatures. The detected mirror modes are likely generated upstream of the observation and have been modified by the plasma.
Tomas Karlsson, Henriette Trollvik, Savvas Raptis, Hans Nilsson, and Hadi Madanian
Ann. Geophys., 40, 687–699, https://doi.org/10.5194/angeo-40-687-2022, https://doi.org/10.5194/angeo-40-687-2022, 2022
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Magnetic holes are curious localized dropouts of magnetic field strength in the solar wind (the flow of ionized gas continuously streaming out from the sun). In this paper we show that these magnetic holes can cross the bow shock (where the solar wind brake down to subsonic velocity) and enter the region close to Earth’s magnetosphere. These structures may therefore represent a new type of non-uniform solar wind–magnetosphere interaction.
Katharina Ostaszewski, Karl-Heinz Glassmeier, Charlotte Goetz, Philip Heinisch, Pierre Henri, Sang A. Park, Hendrik Ranocha, Ingo Richter, Martin Rubin, and Bruce Tsurutani
Ann. Geophys., 39, 721–742, https://doi.org/10.5194/angeo-39-721-2021, https://doi.org/10.5194/angeo-39-721-2021, 2021
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Plasma waves are an integral part of cometary physics, as they facilitate the transfer of energy and momentum. From intermediate to strong activity, nonlinear asymmetric plasma and magnetic field enhancements dominate the inner coma of 67P/CG. We present a statistical survey of these structures from December 2014 to June 2016, facilitated by Rosetta's unprecedented long mission duration. Using a 1D MHD model, we show they can be described as a combination of nonlinear and dissipative effects.
Martin Volwerk, David Mautner, Cyril Simon Wedlund, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Schmid, Diana Rojas-Castillo, Owen W. Roberts, and Ali Varsani
Ann. Geophys., 39, 239–253, https://doi.org/10.5194/angeo-39-239-2021, https://doi.org/10.5194/angeo-39-239-2021, 2021
Short summary
Short summary
The magnetic field in the solar wind is not constant but varies in direction and strength. One of these variations shows a strong local reduction of the magnetic field strength and is called a magnetic hole. These holes are usually an indication that there is, or has been, a temperature difference in the plasma of the solar wind, with the temperature along the magnetic field lower than perpendicular. The MMS spacecraft data have been used to study the characteristics of these holes near Earth.
Herbert Gunell, Charlotte Goetz, Elias Odelstad, Arnaud Beth, Maria Hamrin, Pierre Henri, Fredrik L. Johansson, Hans Nilsson, and Gabriella Stenberg Wieser
Ann. Geophys., 39, 53–68, https://doi.org/10.5194/angeo-39-53-2021, https://doi.org/10.5194/angeo-39-53-2021, 2021
Short summary
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When the magnetised solar wind meets the plasma surrounding a comet, the magnetic field is enhanced in front of the comet, and the field lines are draped around it. This happens because electric currents are induced in the plasma. When these currents flow through the plasma, they can generate waves. In this article we present observations of ion acoustic waves, which is a kind of sound wave in the plasma, detected by instruments on the Rosetta spacecraft near comet 67P/Churyumov–Gerasimenko.
Arianna Piccialli, Julie A. Rathbun, Anny-Chantal Levasseur-Regourd, Anni Määttänen, Anna Milillo, Miriam Rengel, Alessandra Rotundi, Matt Taylor, Olivier Witasse, Francesca Altieri, Pierre Drossart, and Ann Carine Vandaele
Adv. Geosci., 53, 169–182, https://doi.org/10.5194/adgeo-53-169-2020, https://doi.org/10.5194/adgeo-53-169-2020, 2020
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As a way of measuring success in planetary science, we analyzed the participation of female scientists in ESA Solar System missions: we counted the original science team members of 10 missions over a period of 38 years and determined the percentage of women within each team. Although the number of female scientists in the field has been constantly increasing in Europe, we found that gender gaps that existed 38 years ago have persisted into the present.
Audrey Schillings, Herbert Gunell, Hans Nilsson, Alexandre De Spiegeleer, Yusuke Ebihara, Lars G. Westerberg, Masatoshi Yamauchi, and Rikard Slapak
Ann. Geophys., 38, 645–656, https://doi.org/10.5194/angeo-38-645-2020, https://doi.org/10.5194/angeo-38-645-2020, 2020
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The Earth's atmosphere is constantly losing molecules and charged particles, amongst them oxygen ions or O+. Quantifying this loss provides information about the evolution of the atmosphere on geological timescales. In this study, we investigate the final destination of O+ observed with Cluster satellites in a high-altitude magnetospheric region (plasma mantle) by tracing the particles forward in time using simulations. We find that approximately 98 % of O+ escapes the Earth's magnetosphere.
Karl-Heinz Glassmeier
Hist. Geo Space. Sci., 11, 71–80, https://doi.org/10.5194/hgss-11-71-2020, https://doi.org/10.5194/hgss-11-71-2020, 2020
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The German Geophysical Society was founded in 1922 as the Deutsche Seismologische Vereinigung. One of the 24 founders of this society was Karl Friedrich Almstedt. Born in 1891 and deceased in 1964, Almstedt represents a generation of academics and scientists who grew up during the decline of the European empires, experiencing the devastations of the two World Wars and the cruelties of the Nazi era as well as the resurrection of academic and cultural life in post-war Germany.
Martin Volwerk, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Heyner, and Brian Anderson
Ann. Geophys., 38, 51–60, https://doi.org/10.5194/angeo-38-51-2020, https://doi.org/10.5194/angeo-38-51-2020, 2020
Short summary
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The magnetic field that is carried by the solar wind slowly decreases in strength as it moves further from the Sun. However, there are sometimes localized decreases in the magnetic field strength, called magnetic holes. These are small structures where the magnetic field strength decreases to less than 50 % of the surroundings and the plasma density increases. This paper presents a statistical study of the behaviour of these holes between Mercury and Venus using MESSENGER data.
Thomas Honig, Olivier G. Witasse, Hugh Evans, Petteri Nieminen, Erik Kuulkers, Matt G. G. T. Taylor, Bernd Heber, Jingnan Guo, and Beatriz Sánchez-Cano
Ann. Geophys., 37, 903–918, https://doi.org/10.5194/angeo-37-903-2019, https://doi.org/10.5194/angeo-37-903-2019, 2019
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We analysed data from radiation monitors aboard different spacecraft such as Rosetta and Integral. From the data, we extracted the evolution of galactic cosmic rays as a function of time (over a full solar cycle) and position (from 1 to 4.5 AU). In the main results, we confirm the overall evolution (anti-correlation) of the fluxes with respect to the solar activity. We found a surprising result, which is a decrease in the flux of galactic cosmic rays around comet 67P.
Evelyn Liebert, Christian Nabert, and Karl-Heinz Glassmeier
Ann. Geophys., 36, 1073–1080, https://doi.org/10.5194/angeo-36-1073-2018, https://doi.org/10.5194/angeo-36-1073-2018, 2018
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At the bow shock the solar wind is slowed down in front of Earth's magnetosphere. This is accompanied by a gain in strength of the magnetic field, which implies that the bow shock carries electric currents. We present the a comprehensive statistical study of bow shock currents making use of multi-point data collected by Cluster spacecraft. We find that the currents depend on the shock geometry and the interplanetary magnetic field and are in good accordance with theory and simulation results.
Audrey Schillings, Hans Nilsson, Rikard Slapak, Masatoshi Yamauchi, and Lars-Göran Westerberg
Ann. Geophys., 35, 1341–1352, https://doi.org/10.5194/angeo-35-1341-2017, https://doi.org/10.5194/angeo-35-1341-2017, 2017
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The Earth's atmosphere is constantly losing ions and in particular oxygen ions. This phenomenon is important to understand the atmospheric evolution on a large timescale. In this study, the O+ outflow is estimated during six extreme geomagnetic storms using the European Cluster mission data. These estimations are compared with average magnetospheric conditions and show that during those six extreme storms, the O+ outflow is approximately 2 orders of magnitude higher.
Rikard Slapak, Maria Hamrin, Timo Pitkänen, Masatoshi Yamauchi, Hans Nilsson, Tomas Karlsson, and Audrey Schillings
Ann. Geophys., 35, 869–877, https://doi.org/10.5194/angeo-35-869-2017, https://doi.org/10.5194/angeo-35-869-2017, 2017
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The ion total transports in the near-Earth plasma sheet have been investigated and quantified. Specifically, the net O+ transport is about 1024 s−1 in the earthward direction, which is 1 order of magnitude smaller than the typical O+ ionospheric outflows, strongly indicating that most outflow will eventually escape, leading to significant atmospheric loss. The study also shows that low-velocity flows (< 100 km s−1) dominate the mass transport in the near-Earth plasma sheet.
Rikard Slapak, Audrey Schillings, Hans Nilsson, Masatoshi Yamauchi, Lars-Göran Westerberg, and Iannis Dandouras
Ann. Geophys., 35, 721–731, https://doi.org/10.5194/angeo-35-721-2017, https://doi.org/10.5194/angeo-35-721-2017, 2017
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In this study, we have used Cluster satellite data to quantify the ionospheric oxygen ion (O+) escape into the solar wind and its dependence on geomagnetic activity. During times of high activity, the escape may be 2 orders of magnitude higher than under quiet conditions, strongly suggesting that the escape rate was much higher when the Sun was young. The results are important for future studies regarding atmospheric loss over geological timescales.
Evelyn Liebert, Christian Nabert, Christopher Perschke, Karl-Heinz Fornaçon, and Karl-Heinz Glassmeier
Ann. Geophys., 35, 645–657, https://doi.org/10.5194/angeo-35-645-2017, https://doi.org/10.5194/angeo-35-645-2017, 2017
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We present a statistical survey of current magnitudes, directions and locations at the high-latitude day-side magnetopause using Cluster's multi-spacecraft data. Our results show that the magnetopause current flow directions match expectations based on existing models and simulations. Current magnitudes are in correspondence with former studies. In addition, we observe a varying location of the currents with respect to changes in the ambient plasma properties.
Christian Nabert, Carsten Othmer, and Karl-Heinz Glassmeier
Ann. Geophys., 35, 613–628, https://doi.org/10.5194/angeo-35-613-2017, https://doi.org/10.5194/angeo-35-613-2017, 2017
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The interaction of the solar wind with a planetary magnetic field causes electrical currents that modify the magnetic field distribution around the planet. We present an approach to estimating the planetary magnetic field contribution by minimizing the misfit between simulation results and in situ spacecraft data. The approach is developed with respect to the upcoming BepiColombo mission to Mercury aimed at determining the planet's magnetic field.
Christian Nabert, Daniel Heyner, and Karl-Heinz Glassmeier
Ann. Geophys., 35, 465–474, https://doi.org/10.5194/angeo-35-465-2017, https://doi.org/10.5194/angeo-35-465-2017, 2017
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Knowledge of planetary magnetic fields provides deep insights into the structure and dynamics of planets. Due to the interaction of a planet with the solar wind plasma, electrical currents are generated which modify the planetary magnetic field outside the planet. New methods are presented to estimate the planetary magnetic field contribution from spacecraft observations. A reduced model of the interaction relates the time-varying observations to the planetary magnetic field magnitude.
Dennis Frühauff, Johannes Z. D. Mieth, and Karl-Heinz Glassmeier
Ann. Geophys., 35, 253–262, https://doi.org/10.5194/angeo-35-253-2017, https://doi.org/10.5194/angeo-35-253-2017, 2017
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The determination of the polytropic index the plasma sheet of Earth's magnetosphere using THEMIS data. The data set reveals that the active magnetotail density and pressure data are well correlated. Yet, considering broad distributions of specific entropies, the evaluation is best performed on shorter timescales.
Dennis Frühauff, Ferdinand Plaschke, and Karl-Heinz Glassmeier
Ann. Geophys., 35, 117–121, https://doi.org/10.5194/angeo-35-117-2017, https://doi.org/10.5194/angeo-35-117-2017, 2017
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Vector magnetic field instruments mounted on spacecraft require precise in-flight calibration of the offsets of all three axes, i.e., the output in vanishing ambient field. While calibration of the spin plane offsets is trivial, we apply a new technique for determining the spin axis offset, not relying on solar wind data but on magnetosheath encounters. This technique is successfully applied to the satellites of the THEMIS mission to update the calibration parameters of the complete mission.
Martin Volwerk, Daniel Schmid, Bruce T. Tsurutani, Magda Delva, Ferdinand Plaschke, Yasuhito Narita, Tielong Zhang, and Karl-Heinz Glassmeier
Ann. Geophys., 34, 1099–1108, https://doi.org/10.5194/angeo-34-1099-2016, https://doi.org/10.5194/angeo-34-1099-2016, 2016
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The behaviour of mirror mode waves in Venus's magnetosheath is investigated for solar minimum and maximum conditions. It is shown that the total observational rate of these waves does not change much; however, the distribution over the magnetosheath is significantly different, as well as the growth and decay of the waves during these different solar activity conditions.
Patrick Meier, Karl-Heinz Glassmeier, and Uwe Motschmann
Ann. Geophys., 34, 691–707, https://doi.org/10.5194/angeo-34-691-2016, https://doi.org/10.5194/angeo-34-691-2016, 2016
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A new type of wave has been detected by the magnetometer of the Rosetta spacecraft close to comet P67/Churyumov-Gerasimenko. We provide the analytical model of this wave excitation from linear perturbation theory. A modified ion-Weibel instability is identified as source of this wave excited by a cometary current. The waves predominantly grow perpendicular to this current. A fan-like phase structure results from superposing the strongest growing waves in a cometary rest frame.
Maik Riechert, Andrew P. Walsh, Alexander Gerst, and Matthew G. G. T. Taylor
Geosci. Instrum. Method. Data Syst., 5, 289–304, https://doi.org/10.5194/gi-5-289-2016, https://doi.org/10.5194/gi-5-289-2016, 2016
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Astronauts on board the International Space Station have taken thousands of high-quality images of the northern and southern lights (aurorae). Because the images were not taken as part of a specific research project, no information about exactly where the camera was pointing was available. We have used the stars in the images to reconstruct this information. Now we can tell the latitudes and longitudes of the aurorae in the images and use them for research. The data are publicly available.
Ingo Richter, Hans-Ulrich Auster, Gerhard Berghofer, Chris Carr, Emanuele Cupido, Karl-Heinz Fornaçon, Charlotte Goetz, Philip Heinisch, Christoph Koenders, Bernd Stoll, Bruce T. Tsurutani, Claire Vallat, Martin Volwerk, and Karl-Heinz Glassmeier
Ann. Geophys., 34, 609–622, https://doi.org/10.5194/angeo-34-609-2016, https://doi.org/10.5194/angeo-34-609-2016, 2016
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We have analysed the magnetic field measurements performed on the ROSETTA orbiter and the lander PHILAE during PHILAE's descent to comet 67P/Churyumov-Gerasimenko on 12 November 2014. We observed a new type of low-frequency wave with amplitudes of ~ 3 nT, frequencies of 20–50 mHz, wavelengths of ~ 300 km, and propagation velocities of ~ 6 km s−1. The waves are generated in a ~ 100 km region around the comet a show a highly correlated behaviour, which could only be determined by two-point observations.
Christian Nabert and Karl-Heinz Glassmeier
Ann. Geophys., 34, 421–425, https://doi.org/10.5194/angeo-34-421-2016, https://doi.org/10.5194/angeo-34-421-2016, 2016
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Electrical resistivity can influence the occurrence of shock waves. We derive analytically necessary conditions for shocks in a nonuniform resistive magnetohydrodynamic plasma. The nonuniform resistivity significantly modifies the characteristic velocity of wave propagation. A sufficient gradient of the resistivity in a diffusion region can satisfy the necessary condition for the occurrence of slow shocks, which is related to Petschek reconnection.
Dennis Frühauff and Karl-Heinz Glassmeier
Ann. Geophys., 34, 399–409, https://doi.org/10.5194/angeo-34-399-2016, https://doi.org/10.5194/angeo-34-399-2016, 2016
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This study presents an investigation on the occurrence of fast flows in the magnetotail using the complete available data set of the THEMIS spacecraft for the years 2007 to 2015. First, basic statistical findings concerning velocity distributions, occurrence rates, group structures and key features of 16 000 events are presented using Superposed Epoch and Minimum Variance Analysis techniques.
Y. Narita, E. Marsch, C. Perschke, K.-H. Glassmeier, U. Motschmann, and H. Comişel
Ann. Geophys., 34, 393–398, https://doi.org/10.5194/angeo-34-393-2016, https://doi.org/10.5194/angeo-34-393-2016, 2016
Y. Narita, R. Nakamura, W. Baumjohann, K.-H. Glassmeier, U. Motschmann, and H. Comişel
Ann. Geophys., 34, 85–89, https://doi.org/10.5194/angeo-34-85-2016, https://doi.org/10.5194/angeo-34-85-2016, 2016
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Four-spacecraft Cluster observations of turbulent fluctuations in the magnetic reconnection region in the geomagnetic tail show for the first time an indication of ion Bernstein waves, electromagnetic waves that propagate nearly perpendicular to the mean magnetic field and are in resonance with ions. Bernstein waves may influence current sheet dynamics in the reconnection outflow such as a bifurcation of the current sheet.
M. Volwerk, I. Richter, B. Tsurutani, C. Götz, K. Altwegg, T. Broiles, J. Burch, C. Carr, E. Cupido, M. Delva, M. Dósa, N. J. T. Edberg, A. Eriksson, P. Henri, C. Koenders, J.-P. Lebreton, K. E. Mandt, H. Nilsson, A. Opitz, M. Rubin, K. Schwingenschuh, G. Stenberg Wieser, K. Szegö, C. Vallat, X. Vallieres, and K.-H. Glassmeier
Ann. Geophys., 34, 1–15, https://doi.org/10.5194/angeo-34-1-2016, https://doi.org/10.5194/angeo-34-1-2016, 2016
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The solar wind magnetic field drapes around the active nucleus of comet 67P/CG, creating a magnetosphere. The solar wind density increases and with that the pressure, which compresses the magnetosphere, increasing the magnetic field strength near Rosetta. The higher solar wind density also creates more ionization through collisions with the gas from the comet. The new ions are picked-up by the magnetic field and generate mirror-mode waves, creating low-field high-density "bottles" near 67P/CG.
C. Nabert, C. Othmer, and K.-H. Glassmeier
Ann. Geophys., 33, 1513–1524, https://doi.org/10.5194/angeo-33-1513-2015, https://doi.org/10.5194/angeo-33-1513-2015, 2015
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The solar wind plasma interacts with a planetary magnetic field. A magnetohydrodynamic model is used to simulate the interaction and resulting plasma flow. The model uses solar wind inflow parameters as boundary condition. Spacecraft data of the interaction region are compared to the flow model. The solar wind boundary parameters are varied until the model matches the data. With a time-resolution of about 10min, the time-dependent solar wind boundary parameters were reconstructed from the data.
H. Gunell, L. Andersson, J. De Keyser, and I. Mann
Ann. Geophys., 33, 1331–1342, https://doi.org/10.5194/angeo-33-1331-2015, https://doi.org/10.5194/angeo-33-1331-2015, 2015
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In a simulation study of the downward current region of the aurora, i.e. where electrons are accelerated upward, double layers are seen to form at low altitude and move upward until they are disrupted at altitudes of ten thousand kilometres or thereabouts. When one double layer is disrupted a new one forms below, and the process repeats itself. The repeated demise and reformation allows ions to flow upward without passing through the double layers that otherwise would have kept them down.
L. Dai, C. Wang, V. Angelopoulos, and K.-H. Glassmeier
Ann. Geophys., 33, 1147–1153, https://doi.org/10.5194/angeo-33-1147-2015, https://doi.org/10.5194/angeo-33-1147-2015, 2015
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Magnetic reconnection is a ubiquitous process that drives global-scale dynamics in plasmas. For reconnection to proceed, both ion and electrons must be unfrozen in a localized diffusion region. By analyzing in situ measurements, we show that the non-gyrotropic ion pressure is mainly responsible for breaking the ion frozen-in condition in reconnection. The reported non-gyrotropic ion pressure tensor can specify the reconnection electric field that controls how quickly reconnection proceeds.
I. Richter, C. Koenders, H.-U. Auster, D. Frühauff, C. Götz, P. Heinisch, C. Perschke, U. Motschmann, B. Stoll, K. Altwegg, J. Burch, C. Carr, E. Cupido, A. Eriksson, P. Henri, R. Goldstein, J.-P. Lebreton, P. Mokashi, Z. Nemeth, H. Nilsson, M. Rubin, K. Szegö, B. T. Tsurutani, C. Vallat, M. Volwerk, and K.-H. Glassmeier
Ann. Geophys., 33, 1031–1036, https://doi.org/10.5194/angeo-33-1031-2015, https://doi.org/10.5194/angeo-33-1031-2015, 2015
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We present a first report on magnetic field measurements made in the coma of comet 67P/C-G in its low-activity state. The plasma environment is dominated by quasi-coherent, large-amplitude, compressional magnetic field oscillations around 40mHz, differing from the observations at strongly active comets where waves at the cometary ion gyro-frequencies are the main feature. We propose a cross-field current instability associated with the newborn cometary ions as a possible source mechanism.
R. Slapak, H. Nilsson, L. G. Westerberg, and R. Larsson
Ann. Geophys., 33, 301–307, https://doi.org/10.5194/angeo-33-301-2015, https://doi.org/10.5194/angeo-33-301-2015, 2015
H. Gunell, L. Andersson, J. De Keyser, and I. Mann
Ann. Geophys., 33, 279–293, https://doi.org/10.5194/angeo-33-279-2015, https://doi.org/10.5194/angeo-33-279-2015, 2015
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In this paper, we simulate the plasma on a magnetic field line above the aurora. Initially, about half of the acceleration voltage is concentrated in a thin double layer at a few thousand km altitude. When the voltage is lowered, electrons trapped between the double layer and the magnetic mirror are released. In the process we see formation of electron beams and phase space holes. A temporary reversal of the polarity of the double layer is also seen as well as hysteresis effects in its position.
T. Pitkänen, M. Hamrin, P. Norqvist, T. Karlsson, H. Nilsson, A. Kullen, S. M. Imber, and S. E. Milan
Ann. Geophys., 33, 245–255, https://doi.org/10.5194/angeo-33-245-2015, https://doi.org/10.5194/angeo-33-245-2015, 2015
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An azimuthal velocity shear with a reversal within an earthward magnetotail fast flow is studied using Cluster observations. In addition, ionospheric SuperDARN data and different magnetospheric models (T96 and TF04) are utilized when interpreting the Cluster observations. Untwisting of twisted tail B field lines is a good candidate to explain the observations.
M. Volwerk, K.-H. Glassmeier, M. Delva, D. Schmid, C. Koenders, I. Richter, and K. Szegö
Ann. Geophys., 32, 1441–1453, https://doi.org/10.5194/angeo-32-1441-2014, https://doi.org/10.5194/angeo-32-1441-2014, 2014
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We discuss three flybys (within an 8-day time span) of comet 1P/Halley by VEGA 1, 2 and Giotto. Looking at two different plasma phenomena: mirror mode waves and field line draping; we study the differences in SW--comet interaction between these three flybys. We find that on this time scale (comparable to Rosetta's orbits) there is a significant difference, both caused by changing outgassing rate of the comet and changes in the solar wind. We discuss implications for Rosetta RPC observations.
I. A. Barghouthi, H. Nilsson, and S. H. Ghithan
Ann. Geophys., 32, 1043–1057, https://doi.org/10.5194/angeo-32-1043-2014, https://doi.org/10.5194/angeo-32-1043-2014, 2014
H. Gunell, G. Stenberg Wieser, M. Mella, R. Maggiolo, H. Nilsson, F. Darrouzet, M. Hamrin, T. Karlsson, N. Brenning, J. De Keyser, M. André, and I. Dandouras
Ann. Geophys., 32, 991–1009, https://doi.org/10.5194/angeo-32-991-2014, https://doi.org/10.5194/angeo-32-991-2014, 2014
K. Axelsson, T. Sergienko, H. Nilsson, U. Brändström, K. Asamura, and T. Sakanoi
Ann. Geophys., 32, 499–506, https://doi.org/10.5194/angeo-32-499-2014, https://doi.org/10.5194/angeo-32-499-2014, 2014
K.-H. Glassmeier and B. T. Tsurutani
Hist. Geo Space. Sci., 5, 11–62, https://doi.org/10.5194/hgss-5-11-2014, https://doi.org/10.5194/hgss-5-11-2014, 2014
R. Nakamura, F. Plaschke, R. Teubenbacher, L. Giner, W. Baumjohann, W. Magnes, M. Steller, R. B. Torbert, H. Vaith, M. Chutter, K.-H. Fornaçon, K.-H. Glassmeier, and C. Carr
Geosci. Instrum. Method. Data Syst., 3, 1–11, https://doi.org/10.5194/gi-3-1-2014, https://doi.org/10.5194/gi-3-1-2014, 2014
M. Volwerk, C. Koenders, M. Delva, I. Richter, K. Schwingenschuh, M. S. Bentley, and K.-H. Glassmeier
Ann. Geophys., 31, 2201–2206, https://doi.org/10.5194/angeo-31-2201-2013, https://doi.org/10.5194/angeo-31-2201-2013, 2013
C. Perschke, Y. Narita, S. P. Gary, U. Motschmann, and K.-H. Glassmeier
Ann. Geophys., 31, 1949–1955, https://doi.org/10.5194/angeo-31-1949-2013, https://doi.org/10.5194/angeo-31-1949-2013, 2013
H. Gunell, J. De Keyser, E. Gamby, and I. Mann
Ann. Geophys., 31, 1227–1240, https://doi.org/10.5194/angeo-31-1227-2013, https://doi.org/10.5194/angeo-31-1227-2013, 2013
R. Slapak, H. Nilsson, and L. G. Westerberg
Ann. Geophys., 31, 1005–1010, https://doi.org/10.5194/angeo-31-1005-2013, https://doi.org/10.5194/angeo-31-1005-2013, 2013
C. Nabert, K.-H. Glassmeier, and F. Plaschke
Ann. Geophys., 31, 419–437, https://doi.org/10.5194/angeo-31-419-2013, https://doi.org/10.5194/angeo-31-419-2013, 2013
S. Kirkwood, E. Belova, P. Dalin, M. Mihalikova, D. Mikhaylova, D. Murtagh, H. Nilsson, K. Satheesan, J. Urban, and I. Wolf
Ann. Geophys., 31, 333–347, https://doi.org/10.5194/angeo-31-333-2013, https://doi.org/10.5194/angeo-31-333-2013, 2013
A. Alexandrova, R. Nakamura, V. S. Semenov, I. V. Kubyshkin, S. Apatenkov, E. V. Panov, D. Korovinskiy, H. Biernat, W. Baumjohann, K.-H. Glassmeier, and J. P. McFadden
Ann. Geophys., 30, 1727–1741, https://doi.org/10.5194/angeo-30-1727-2012, https://doi.org/10.5194/angeo-30-1727-2012, 2012
K. Axelsson, T. Sergienko, H. Nilsson, U. Brändström, Y. Ebihara, K. Asamura, and M. Hirahara
Ann. Geophys., 30, 1693–1701, https://doi.org/10.5194/angeo-30-1693-2012, https://doi.org/10.5194/angeo-30-1693-2012, 2012
Related subject area
Subject: Magnetosphere & space plasma physics | Keywords: Solar wind interactions with unmagnetized bodies
Effects of ion composition on escape and morphology on Mars
Qi Zhang, Mats Holmström, and Xiao-Dong Wang
Ann. Geophys., 41, 375–388, https://doi.org/10.5194/angeo-41-375-2023, https://doi.org/10.5194/angeo-41-375-2023, 2023
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We improve a method for modeling the interaction between solar wind and Mars that uses a hybrid model to fit the observed bow shock location to determine a corresponding exobase ion upflux. We applied the method to one Mars Atmosphere and Volatile Evolution orbit to study the effects on ion escape estimates of heavy-ion composition in the ionosphere, alpha particles in the solar wind, solar-wind velocity aberration, and electron temperature. We also studied the morphology of the escaping ions.
Cited articles
Balogh, A. and Treumann, R. A.: Physics of Collisionless Shocks, vol. 12 of ISSI Scientific Report Series, Springer, New York, NY, https://doi.org/10.1007/978-1-4614-6099-2, 2013. a, b, c
Balsiger, H., Altwegg, K., Bochsler, P., Eberhardt, P., Fischer, J., Graf, S., Jäckel, A., Kopp, E., Langer, U., Mildner, M., Müller, J., Riesen, T., Rubin, M., Scherer, S., Wurz, P., Wüthrich, S., Arijs, E., Delanoye, S., De Keyser, J., Neefs, E., Nevejans, D., Rème, H., Aoustin, C., Mazelle, C., Médale, J.-L., Sauvaud, J. A., Berthelier, J.-J., Bertaux, J.-L., Duvet, L., Illiano, J.-M., Fuselier, S. A., Ghielmetti, A. G., Magoncelli, T., Shelley, E. G., Korth, A., Heerlein, K., Lauche, H., Livi, S., Loose, A., Mall, U., Wilken, B., Gliem, F., Fiethe, B., Gombosi, T. I., Block, B., Carignan, G. R., Fisk, L. A., Waite, J. H., Young, D. T., and Wollnik, H.: Rosina Rosetta Orbiter Spectrometer for Ion and Neutral Analysis, Space Sci. Rev., 128, 745–801, https://doi.org/10.1007/s11214-006-8335-3, 2007. a
Behar, E., Nilsson, H., Alho, M., Goetz, C., and Tsurutani, B.: The birth and growth of a solar wind cavity around a comet – Rosetta observations, Mon. Not. R. Astron. Soc., 469, S396–S403, https://doi.org/10.1093/mnras/stx1871, 2017. a
Behar, E., Tabone, B., Saillenfest, M., Henri, P., Deca, J., Lindkvist, J., Holmström, M., and Nilsson, H.: A global 2D analytical model of the solar wind dynamics around a comet, Astron. Astrophys., 620, A35, https://doi.org/10.1051/0004-6361/201832736, 2018. a
Besse, S., Vallat, C., Barthelemy, M., Coia, D., Costa, M., De Marchi, G., Fraga, D., Grotheer, E., Heather, D., Lim, T., Martinez, S., Arviset, C., Barbarisi, I., Docasal, R., Macfarlane, A., Rios, C., Saiz, J., and Vallejo, F.: ESA's Planetary Science Archive: Preserve and present reliable scientific data sets, Planet. Space Sci., 150, 131–140, https://doi.org/10.1016/j.pss.2017.07.013, 2018 (data available at: http://archives.esac.esa.int/psa, last access: 28 April 2021). a
Biermann, L., Brosowski, B., and Schmidt, H. U.: The interactions of the solar wind with a comet, Sol. Phys., 1, 254–284, https://doi.org/10.1007/BF00150860, 1967. a, b, c
Breuillard, H., Henri, P., Bucciantini, L., Volwerk, M., Karlsson, T., Eriksson, A., Johansson, F., Odelstad, E., Richter, I., Goetz, C., Vallières, X., and Hajra, R.: The properties of the singing comet waves in the 67P/Churyumov–Gerasimenko plasma environment as observed by the Rosetta mission, Astron. Astrophys., 630, A39, https://doi.org/10.1051/0004-6361/201834876, 2019. a
Burch, J. L., Goldstein, R., Cravens, T. E., Gibson, W. C., Lundin, R. N., Pollock, C. J., Winningham, J. D., and Young, D. T.: RPC-IES: The Ion and Electron Sensor of the Rosetta Plasma Consortium, Space Sci. Rev., 128, 697–712, https://doi.org/10.1007/s11214-006-9002-4, 2007. a
Carr, C., Cupido, E., Lee, C. G. Y., Balogh, A., Beek, T., Burch, J. L., Dunford, C. N., Eriksson, A. I., Gill, R., Glassmeier, K. H., Goldstein, R., Lagoutte, D., Lundin, R., Lundin, K., Lybekk, B., Michau, J. L., Musmann, G., Nilsson, H., Pollock, C., Richter, I., and Trotignon, J. G.: RPC: The Rosetta Plasma Consortium, Space Sci. Rev., 128, 629–647, https://doi.org/10.1007/s11214-006-9136-4, 2007. a
Coates, A. J., Johnstone, A. D., Kessel, R. L., Huddleston, D. E., and Wilken, B.: Plasma Parameters Near the Comet Halley Bow Shock, J. Geophys. Res., 95, 20701–20716, https://doi.org/10.1029/JA095iA12p20701, 1990. a, b
Coates, A. J., Johnstone, A. D., and Neubauer, F. M.: Cometary ion pressure anisotropies at comets Halley and Grigg-Skjellerup, J. Geophys. Res., 101, 27573–27584, https://doi.org/10.1029/96JA02524, 1996. a
Coates, A. J., Mazelle, C., and Neubauer, F. M.: Bow shock analysis at comets Halley and Grigg-Skjellerup, J. Geophys. Res., 102, 7105–7113, https://doi.org/10.1029/96JA04002, 1997. a
Coates, A. J., Burch, J. L., Goldstein, R., Nilsson, H., Wieser, G. S., Behar, E., and the RPC team: Ion pickup observed at comet 67P with the Rosetta Plasma Consortium (RPC) particle sensors: similarities with previous observations and AMPTE releases, and effects of increasing activity, J. Phys. Conf. Ser., 642, 012005, https://doi.org/10.1088/1742-6596/642/1/012005, 2015. a
Deca, J., Divin, A., Henri, P., Eriksson, A., Markidis, S., Olshevsky, V., and Horányi, M.: Electron and Ion Dynamics of the Solar Wind Interaction with a Weakly Outgassing Comet, Phys. Rev. Lett., 118, 205101, https://doi.org/10.1103/PhysRevLett.118.205101, 2017. a
Edberg, N. J. T., Eriksson, A. I., Odelstad, E., Vigren, E., Andrews, D. J., Johansson, F., Burch, J. L., Carr, C. M., Cupido, E., Glassmeier, K.-H., Goldstein, R., Halekas, J. S., Henri, P., Koenders, C., Mandt, K., Mokashi, P., Nemeth, Z., Nilsson, H., Ramstad, R., Richter, I., and Wieser, G. S.: Solar wind interaction with comet 67P: Impacts of corotating interaction regions, J. Geophys. Res.-Space, 121, 949–965, https://doi.org/10.1002/2015JA022147, 2016. a
Edberg, N. J. T., Eriksson, A. I., Vigren, E., Johansson, F. L., Goetz, C., Nilsson, H., Gilet, N., and Henri, P.: The Convective Electric Field Influence on the Cold Plasma and Diamagnetic Cavity of Comet 67P, Astronom. J., 158, 71, https://doi.org/10.3847/1538-3881/ab2d28, 2019. a, b
Eriksson, A. I., Boström, R., Gill, R., Åhlén, L., Jansson, S.-E., Wahlund, J.-E., André, M., Mälkki, A., Holtet, J. A., Lybekk, B., Pedersen, A., and Blomberg, L. G.: RPC-LAP: The Rosetta Langmuir Probe Instrument, Space Sci. Rev., 128, 729–744, https://doi.org/10.1007/s11214-006-9003-3, 2007. a
Fahr, H. J. and Siewert, M.: Entropy generation at multi-fluid magnetohydrodynamic shocks with emphasis to the solar wind termination
shock, Astron. Astrophys., 576, A100, https://doi.org/10.1051/0004-6361/201424485, 2015. a, b
Flammer, K. R. and Mendis, D. A.: A note on the mass-loaded MHD flow of the solar wind towards a cometary nucleus, Astrophys. Space Sci., 182, 155–162, https://doi.org/10.1007/BF00646450, 1991. a
Glassmeier, K.-H.: Interaction of the solar wind with comets: A Rosetta perspective, Philos. T. Roy. Soc. A, 375, 20160256, https://doi.org/10.1098/rsta.2016.0256, 2017. a
Glassmeier, K.-H., Boehnhardt, H., Koschny, D., Kührt, E., and Richter, I.: The Rosetta Mission: Flying Towards the Origin of the Solar System, Space Sci. Rev., 128, 1–21, https://doi.org/10.1007/s11214-006-9140-8, 2007a. a
Glassmeier, K.-H., Richter, I., Diedrich, A., Musmann, G., Auster, U., Motschmann, U., Balogh, A., Carr, C., Cupido, E., Coates, A., Rother, M., Schwingenschuh, K., Szegö, K., and Tsurutani, B.: RPC-MAG The Fluxgate Magnetometer in the ROSETTA Plasma Consortium, Space Sci. Rev., 128, 649–670, https://doi.org/10.1007/s11214-006-9114-x, 2007b. a
Goetz, C., Koenders, C., Hansen, K. C., Burch, J., Carr, C., Eriksson, A., Frühauff, D., Güttler, C., Henri, P., Nilsson, H., Richter, I., Rubin, M., Sierks, H., Tsurutani, B., Volwerk, M., and Glassmeier, K. H.: Structure and evolution of the diamagnetic cavity at comet 67P/Churyumov-Gerasimenko, Mon. Not. R. Astron. Soc., 462, S459–S467, https://doi.org/10.1093/mnras/stw3148, 2016a. a, b
Goetz, C., Koenders, C., Richter, I., Altwegg, K., Burch, J., Carr, C., Cupido, E., Eriksson, A., Güttler, C., Henri, P., Mokashi, P., Nemeth, Z., Nilsson, H., Rubin, M., Sierks, H., Tsurutani, B., Vallat, C., Volwerk, M., and Glassmeier, K.-H.: First detection of a diamagnetic cavity at comet 67P/Churyumov-Gerasimenko, Astron. Astrophys., 588, A24, https://doi.org/10.1051/0004-6361/201527728, 2016b. a
Goetz, C., Volwerk, M., Richter, I., and Glassmeier, K.-H.: Evolution of the magnetic field at comet 67P/Churyumov-Gerasimenko, Mon. Not. R. Astron. Soc., 469, S268–S275, https://doi.org/10.1093/mnras/stx1570, 2017. a, b
Götz, C., Gunell, H., Volwerk, M., Beth, A., Eriksson, A., Galand, M., Henri, P., Nilsson, H., Wedlund, C. S., Alho, M., Andersson, L., Andre, N., De Keyser, J., Deca, J., Ge, Y., Glaßmeier, K.-H., Hajra, R., Karlsson, T., Kasahara, S., Kolmasova, I., LLera, K., Madanian, H., Mann, I., Mazelle, C., Odelstad, E., Plaschke, F., Rubin, M., Sanchez-Cano, B., Snodgrass, C., and Vigren, E.: Cometary Plasma Science – A White Paper in response to the Voyage 2050 Call by the European Space Agency, arXiv [preprint], arXiv:1908.00377, 1 August 2019. a, b, c
Gunell, H., Goetz, C., Simon Wedlund, C., Lindkvist, J., Hamrin, M., Nilsson, H., Llera, K., Eriksson, A., and Holmström, M.: The infant bow shock: a new frontier at a weak activity comet, Astron. Astrophys., 619, L2, https://doi.org/10.1051/0004-6361/201834225, 2018. a, b, c, d, e, f, g, h, i, j, k, l, m
Gunell, H., Lindkvist, J., Goetz, C., Nilsson, H., and Hamrin, M.: Polarisation of a small-scale cometary plasma environment: Particle-in-cell modelling of comet 67P/Churyumov-Gerasimenko, Astron. Astrophys., 631, A174, https://doi.org/10.1051/0004-6361/201936004, 2019. a
Hall, B. E. S., Lester, M., Sánchez‐Cano, B., Nichols, J. D., Andrews, D. J., Edberg, N. J. T., Opgenoorth, H. J., Fränz, M., Holmström, M., Ramstad, R., Witasse, O., Cartacci, M., Cicchetti, A., Noschese, R., and Orosei, R.: Annual variations in the Martian bow shock location as observed by the Mars Express mission, J. Geophys. Res.-Space, 121, 11474–11494, https://doi.org/10.1002/2016JA023316, 2016. a
Haser, L.: Distribution d'intensité dans la tête d'une comète, Bulletin de la Societe Royale des Sciences de Liege, 43, 740–750, 1957. a
Hässig, M., Altwegg, K., Balsiger, H., Bar-Nun, A., Berthelier, J. J., Bieler, A., Bochsler, P., Briois, C., Calmonte, U., Combi, M., De Keyser, J., Eberhardt, P., Fiethe, B., Fuselier, S. A., Galand, M., Gasc, S., Gombosi, T. I., Hansen, K. C., Jäckel, A., Keller, H. U., Kopp, E., Korth, A., Kührt, E., Le Roy, L., Mall, U., Marty, B., Mousis, O., Neefs, E., Owen, T., Rème, H., Rubin, M., Sémon, T., Tornow, C., Tzou, C.-Y., Waite, J. H., and Wurz, P.: Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko, Science, 347, aaa0276, https://doi.org/10.1126/science.aaa0276, 2015. a
Johansson, F. L., Eriksson, A. I., Gilet, N., Henri, P., Wattieaux, G., Taylor, M. G. G. T., Imhof, C., and Cipriani, F.: A charging model for the Rosetta spacecraft, Astron. Astrophys., 642, A43, https://doi.org/10.1051/0004-6361/202038592, 2020. a, b
Kessel, R. L., Coates, A. J., Motschmann, U., and Neubauer, F. M.: Shock normal determination for multiple-ion shocks, J. Geophys. Res., 99, 19359–19374, https://doi.org/10.1029/94JA01234, 1994. a
Koenders, C., Glassmeier, K.-H., Richter, I., Motschmann, U., and Rubin, M.: Revisiting cometary bow shock positions, Planet. Space Sci., 87, 85–95, https://doi.org/10.1016/j.pss.2013.08.009, 2013. a
Koenders, C., Goetz, C., Richter, I., Motschmann, U., and Glassmeier, K.-H.: Magnetic field pile-up and draping at intermediately active comets: results from comet 67P/Churyumov-Gerasimenko at 2.0 AU, Mon. Not. R. Astron. Soc., 462, S235–S241, https://doi.org/10.1093/mnras/stw2480, 2016a. a
Koenders, C., Perschke, C., Goetz, C., Richter, I., Motschmann, U., and Glassmeier, K. H.: Low-frequency waves at comet 67P/Churyumov-Gerasimenko. Observations compared to numerical simulations, Astron. Astrophys., 594, A66, https://doi.org/10.1051/0004-6361/201628803, 2016b. a, b
Lavraud, B. and Larson, D. E.: Correcting moments of in situ particle distribution functions for spacecraft electrostatic charging, J. Geophys. Res.-Space, 121, 8462–8474, https://doi.org/10.1002/2016JA022591, 2016. a
Lindkvist, J., Hamrin, M., Gunell, H., Nilsson, H., Simon Wedlund, C., Kallio, E., Mann, I., Pitkänen, T., and Karlsson, T.: Energy conversion in cometary atmospheres Hybrid modeling of 67P/Churyumov-Gerasimenko, Astron. Astrophys., 616, A81, https://doi.org/10.1051/0004-6361/201732353, 2018. a, b, c, d
Madanian, H., Burch, J. L., Eriksson, A. I., Cravens, T. E., Galand, M., Vigren, E., Goldstein, R., Nemeth, Z., Mokashi, P., Richter, I., and Rubin, M.: Electron dynamics near diamagnetic regions of comet 67P/Churyumov-Gerasimenko, Planet. Space Sci., 187, 104924, https://doi.org/10.1016/j.pss.2020.104924, 2020. a
Maggiolo, R., Hamrin, M., De Keyser, J., Pitkänen, T., Cessateur, G., Gunell, H., and Maes, L.: The Delayed Time Response of Geomagnetic Activity to the Solar Wind, J. Geophys. Res.-Space, 122, 11109–11127, https://doi.org/10.1002/2016JA023793, 2017. a
Mandt, K. E., Eriksson, A., Edberg, N. J. T., Koenders, C., Broiles, T., Fuselier, S. A., Henri, P., Nemeth, Z., Alho, M., Biver, N., Beth, A., Burch, J., Carr, C., Chae, K., Coates, A. J., Cupido, E., Galand, M., Glassmeier, K.-H., Goetz, C., Goldstein, R., Hansen, K. C., Haiducek, J., Kallio, E., Lebreton, J.-P., Luspay-Kuti, A., Mokashi, P., Nilsson, H., Opitz, A., Richter, I., Samara, M., Szego, K., Tzou, C.-Y., Volwerk, M., Simon Wedlund, C., and Stenberg Wieser, G.: RPC observation of the development and evolution
of plasma interaction boundaries at 67P/Churyumov-Gerasimenko, Mon. Not. R. Astron. Soc., 462, S9–S22, https://doi.org/10.1093/mnras/stw1736, 2016. a, b
Martinecz, C., Fränz, M., Woch, J., Krupp, N., Roussos, E., Dubinin, E., Motschmann, U., Barabash, S., Lundin, R., Holmström, M., Andersson, H., Yamauchi, M., Grigoriev, A., Futaana, Y., Brinkfeldt, K., Gunell, H., Frahm, R. A., Winningham, J. D., Sharber, J. R., Scherrer, J., Coates, A. J., Linder, D. R., Kataria, D. O., Kallio, E., Sales, T., Schmidt, W., Riihela, P., Koskinen, H. E. J., Kozyra, J. U., Luhmann, J., Russell, C. T., Roelof, E. C., Brandt, P., Curtis, C. C., Hsieh, K. C., Sandel, B. R., Grande, M., Sauvaud, J.-A., Fedorov, A., Thocaven, J.-J., Mazelle, C., McKenna-Lawler, S., Orsini, S., Cerulli-Irelli, R., Maggi, M., Mura, A., Milillo, A., Wurz, P., Galli, A., Bochsler, P., Asamura, K., Szego, K., Baumjohann, W., Zhang, T. L., and Lammer, H.: Location of the bow shock and ion composition boundaries at Venus–initial determinations from Venus Express ASPERA-4, Planet. Space Sci., 56, 780–784, https://doi.org/10.1016/j.pss.2007.07.007, 2008. a
Motschmann, U., Sauer, K., Roatsch, T., and McKenzie, J. F.: Multiple-ion plasma boundaries, Adv. Space Res., 11, 69–72, https://doi.org/10.1016/0273-1177(91)90013-A, 1991a. a
Motschmann, U., Sauer, K., Roatsch, T., and McKenzie, J. F.: Subcritical multiple-ion shocks, J. Geophys. Res., 96, 13841–13848, https://doi.org/10.1029/91JA00638, 1991b. a
Neubauer, F. M., Glassmeier, K. H., Pohl, M., Raeder, J., Acuña, M. H., Burlaga, L. F., Ness, N. F., Musmann, G., Mariani, F., Wallis, M. K., Ungstrup, E., and Schmidt, H. U.: First results from the Giotto magnetometer experiment at comet Halley, Nature, 321, 352–355, https://doi.org/10.1038/321352a0, 1986. a
Nilsson, H., Lundin, R., Lundin, K., Barabash, S., Borg, H., Norberg, O., Fedorov, A., Sauvaud, J.-A., Koskinen, H., Kallio, E., Riihelä, P., and Burch, J. L.: RPC-ICA: The Ion Composition Analyzer of the Rosetta Plasma Consortium, Space Sci. Rev., 128, 671–695, https://doi.org/10.1007/s11214-006-9031-z, 2007. a
Nilsson, H., Wieser, G. S., Behar, E., Gunell, H., Galand, M., Simon Wedlund, C., Alho, M., Goetz, C., Yamauchi, M., Henri, P., and Eriksson, E. O. A.: Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA, Mon. Not. R. Astron. Soc., 469, S252–S261, https://doi.org/10.1093/mnras/stx1491, 2017. a, b, c, d
Nilsson, H., Gunell, H., Karlsson, T., Brenning, N., Henri, P., Goetz, C., Eriksson, A. I., Behar, E., Stenberg Wieser, G., and Vallières, X.: Size of a plasma cloud matters: The polarisation electric field of a small-scale comet ionosphere, Astron. Astrophys., 616, A50, https://doi.org/10.1051/0004-6361/201833199, 2018. a
Odelstad, E., Eriksson, A. I., Edberg, N. J. T., Johansson, F., Vigren, E., André, M., Tzou, C. Y., Carr, C., and Cupido, E.: Evolution of the plasma environment of comet 67P from spacecraft potential measurements by the Rosetta Langmuir probe instrument, Geophys. Res. Lett., 42, 10126–10134, https://doi.org/10.1002/2015GL066599, 2015. a
Omidi, N. and Winske, D.: A Kinetic Study of Solar Wind Mass Loading and Cometary Bow Shocks, J. Geophys. Res., 92, 13409–13426, https://doi.org/10.1029/JA092iA12p13409, 1987. a, b
Simon Wedlund, C., Alho, M., Gronoff, G., Kallio, E., Gunell, H., Nilsson, H., Lindkvist, J., Behar, E., Stenberg Wieser, G., and Miloch, W. J.: Hybrid modelling of cometary plasma environments. I. Impact of photoionisation, charge exchange, and electron ionisation on bow shock and cometopause at 67P/Churyumov-Gerasimenko, Astron. Astrophys., 604, A73, https://doi.org/10.1051/0004-6361/201730514, 2017. a
Simon Wedlund, C., Behar, E., Nilsson, H., Alho, M., Kallio, E., Gunell, H., Bodewits, D., Heritier, K., Galand, M., Beth, A., Rubin, M., Altwegg, K., Volwerk, M., Gronoff, G., and Hoekstra, R.: Solar wind charge exchange in cometary atmospheres – III. Results from the Rosetta mission to comet 67P/Churyumov-Gerasimenko, Astron. Astrophys., 630, A37, https://doi.org/10.1051/0004-6361/201834881, 2019. a
Smith, E. J., Tsurutani, B. T., Slavin, J. A., Jones, D. E., Siscoe, G. L., and Mendis, D. A.: International Cometary Explorer Encounter with
Giacobini-Zinner: Magnetic Field Observations, Science, 232, 382–385, https://doi.org/10.1126/science.232.4748.382, 1986. a
Snodgrass, C. and Jones, G. H.: The European Space Agency's Comet Interceptor lies in wait, Nat. Commun., 10, 5418, https://doi.org/10.1038/s41467-019-13470-1, 2019. a
Trotignon, J. G., Michau, J. L., Lagoutte, D., Chabassière, M., Chalumeau, G., Colin, F., Décréau, P. M. E., Geiswiller, J., Gille, P., Grard, R., Hachemi, T., Hamelin, M., Eriksson, A., Laakso, H., Lebreton, J. P., Mazelle, C., Randriamboarison, O., Schmidt, W., Smit, A., Telljohann, U., and Zamora, P.: RPC-MIP: the Mutual Impedance Probe of the Rosetta Plasma Consortium, Space Sci. Rev., 128, 713–728, https://doi.org/10.1007/s11214-006-9005-1, 2007. a
Williamson, H. N., Nilsson, H., Stenberg Wieser, G., Eriksson, A. I., Richter, I., and Goetz, C.: Momentum and Pressure Balance of a Comet Ionosphere, Geophys. Res. Lett., 47, e88666, https://doi.org/10.1029/2020GL088666, 2020.
a
Ziegler, H. J. and Schindler, K.: Structure of subcritical perpendicular shock waves, Phys. Fluids, 31, 570–576, https://doi.org/10.1063/1.866839, 1988. a
Short summary
Boundaries in the plasma around comet 67P separate regions with different properties. Many have been identified, including a new boundary called an infant bow shock. Here, we investigate how the plasma and fields behave at this boundary and where it can be found. The main result is that the infant bow shock occurs at intermediate activity and intermediate distances to the comet. Most plasma parameters behave as expected; however, some inconsistencies indicate that the boundary is non-stationary.
Boundaries in the plasma around comet 67P separate regions with different properties. Many have...
