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1. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. -A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E., Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. -A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E.

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors., Comment: 78 pages, 14 figures, published

Published
2022
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2. Flux Enhancements of Field-Aligned Low-Energy O^+ Ion (FALEO) in the Inner Magnetosphere: A Possible Source of Warm Plasma Cloak and Oxygen Torus

Author

Nosé, M., Matsuoka, A., Miyoshi, Y., Asamura, K., Hori, T., Teramoto, M., Shinohara, I., Hirahara, M., Kletzing, C. A., Smith, C. W., MacDowall, R. J., Spence, H. E., Reeves, G. D., Gjerloev, J. W., Nosé, M., Matsuoka, A., Miyoshi, Y., Asamura, K., Hori, T., Teramoto, M., Shinohara, I., Hirahara, M., Kletzing, C. A., Smith, C. W., MacDowall, R. J., Spence, H. E., Reeves, G. D., and Gjerloev, J. W.

Abstract

Flux enhancements of field-aligned low-energy O^+ ion (FALEO) are simultaneously observed by Arase, Van Allen Probes A and B in the nightside inner magnetosphere during 05–07 UT on September 22, 2018. FALEOs appear after a magnetic dipolarization signature with approximately 6–20 min delay. It has the energy-dispersion signature from a few keV to ∼100 eV only in the direction parallel to the magnetic field at Arase, while it decreases its energy from a few keV down to 10 eV in both the parallel and antiparallel directions at Probes A and B. We perform a numerical simulation to trace trajectories of test O^+ ions in a model magnetosphere, which are launched from above the ionosphere 3–15 min after a substorm. Flying virtual satellites that have the same orbits as the real satellites, we create virtual energy-time spectrograms of O^+ ions to compare with the observed ones. Results show a very good correspondence between them, indicating that FALEOs originate from ionospheric O^+ ions that are extracted from the upper ionosphere at substorm onset and flow along the magnetic field toward the geomagnetic equator. It is also revealed that 3–9 hr after their launch, test O^+ ions less than 400 eV have a spatial distribution in the inner magnetosphere which is similar to those of the warm plasma cloak and the oxygen torus. We therefore conclude that FALEO is a source of those cold ion populations.

Published
2022

3. Flux Enhancements of Field-Aligned Low-Energy O^+ Ion (FALEO) in the Inner Magnetosphere: A Possible Source of Warm Plasma Cloak and Oxygen Torus

Author

Nosé, M., Matsuoka, A., Miyoshi, Y., Asamura, K., Hori, T., Teramoto, M., Shinohara, I., Hirahara, M., Kletzing, C. A., Smith, C. W., MacDowall, R. J., Spence, H. E., Reeves, G. D., Gjerloev, J. W., Nosé, M., Matsuoka, A., Miyoshi, Y., Asamura, K., Hori, T., Teramoto, M., Shinohara, I., Hirahara, M., Kletzing, C. A., Smith, C. W., MacDowall, R. J., Spence, H. E., Reeves, G. D., and Gjerloev, J. W.

Abstract

Flux enhancements of field-aligned low-energy O^+ ion (FALEO) are simultaneously observed by Arase, Van Allen Probes A and B in the nightside inner magnetosphere during 05–07 UT on September 22, 2018. FALEOs appear after a magnetic dipolarization signature with approximately 6–20 min delay. It has the energy-dispersion signature from a few keV to ∼100 eV only in the direction parallel to the magnetic field at Arase, while it decreases its energy from a few keV down to 10 eV in both the parallel and antiparallel directions at Probes A and B. We perform a numerical simulation to trace trajectories of test O^+ ions in a model magnetosphere, which are launched from above the ionosphere 3–15 min after a substorm. Flying virtual satellites that have the same orbits as the real satellites, we create virtual energy-time spectrograms of O^+ ions to compare with the observed ones. Results show a very good correspondence between them, indicating that FALEOs originate from ionospheric O^+ ions that are extracted from the upper ionosphere at substorm onset and flow along the magnetic field toward the geomagnetic equator. It is also revealed that 3–9 hr after their launch, test O^+ ions less than 400 eV have a spatial distribution in the inner magnetosphere which is similar to those of the warm plasma cloak and the oxygen torus. We therefore conclude that FALEO is a source of those cold ion populations.

Published
2022

4. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. -A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E., Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. -A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E.

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors., Comment: 78 pages, 14 figures, published

Published
2022
Full Text
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5. Energy Transfer Between Hot Protons and Electromagnetic Ion Cyclotron Waves in Compressional Pc5 Ultra-low Frequency Waves

Author

Kitamura, N., Shoji, M., Nakamura, S., Kitahara, M., Amano, T., Omura, Y., Hasegawa, H., Boardsen, S. A., Miyoshi, Y., Katoh, Y., Teramoto, M., Saito, Y., Yokota, S., Hirahara, M., Gershman, D. J., Giles, B. L., Russell, C. T., Strangeway, R. J., Ahmadi, N., Lindqvist, Per-Arne, Ergun, R. E., Fuselier, S. A., Burch, J. L., Kitamura, N., Shoji, M., Nakamura, S., Kitahara, M., Amano, T., Omura, Y., Hasegawa, H., Boardsen, S. A., Miyoshi, Y., Katoh, Y., Teramoto, M., Saito, Y., Yokota, S., Hirahara, M., Gershman, D. J., Giles, B. L., Russell, C. T., Strangeway, R. J., Ahmadi, N., Lindqvist, Per-Arne, Ergun, R. E., Fuselier, S. A., and Burch, J. L.

Abstract

The Magnetospheric Multiscale (MMS) spacecraft observed many enhancements of electromagnetic ion cyclotron (EMIC) waves in an event in the late afternoon outer magnetosphere. These enhancements occurred mainly in the troughs of magnetic field intensity associated with a compressional ultralow frequency (ULF) wave. The ULF wave had a period of similar to 2-5 min (Pc5 frequency range) and was almost static in the plasma rest frame. The magnetic and ion pressures were in antiphase. They are consistent with mirror-mode type structures. We apply the Wave-Particle Interaction Analyzer method, which can quantitatively investigate the energy transfer between hot anisotropic protons and EMIC waves, to burst-mode data obtained by the four MMS spacecraft. The energy transfer near the cyclotron resonance velocity was identified in the vicinity of the center of troughs of magnetic field intensity, which corresponds to the maxima of ion pressure in the compressional ULF wave. This result is consistent with the idea that the EMIC wave generation is modulated by ULF waves, and preferential locations for the cyclotron resonant energy transfer are the troughs of magnetic field intensity. In these troughs, relatively low resonance velocity due to the lower magnetic field intensity and the enhanced hot proton flux likely contribute to the enhanced energy transfer from hot protons to the EMIC waves by cyclotron resonance. Due to the compressional ULF wave, regions of the cyclotron resonant energy transfer can be narrow (only a few times of the gyroradii of hot resonant protons) in magnetic local time., QC 20210622

Published
2021
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6. Energy Transfer Between Hot Protons and Electromagnetic Ion Cyclotron Waves in Compressional Pc5 Ultra-low Frequency Waves

Author

Kitamura, N., Shoji, M., Nakamura, S., Kitahara, M., Amano, T., Omura, Y., Hasegawa, H., Boardsen, S.A., Miyoshi, Y., Katoh, Y., Teramoto, M., Saito, Y., Yokota, S., Hirahara, M., Gershman, D.J., Giles, B.L., Russell, C.T., Strangeway, R.J., Ahmadi, N., Lindqvist, P.-A., Ergun, R.E., Fuselier, S.A., Burch, J.L., Kitamura, N., Shoji, M., Nakamura, S., Kitahara, M., Amano, T., Omura, Y., Hasegawa, H., Boardsen, S.A., Miyoshi, Y., Katoh, Y., Teramoto, M., Saito, Y., Yokota, S., Hirahara, M., Gershman, D.J., Giles, B.L., Russell, C.T., Strangeway, R.J., Ahmadi, N., Lindqvist, P.-A., Ergun, R.E., Fuselier, S.A., and Burch, J.L.

Abstract

The Magnetospheric Multiscale (MMS) spacecraft observed many enhancements of electromagnetic ion cyclotron (EMIC) waves in an event in the late afternoon outer magnetosphere. These enhancements occurred mainly in the troughs of magnetic field intensity associated with a compressional ultralow frequency (ULF) wave. The ULF wave had a period of ∼2–5 min (Pc5 frequency range) and was almost static in the plasma rest frame. The magnetic and ion pressures were in antiphase. They are consistent with mirror-mode type structures. We apply the Wave-Particle Interaction Analyzer method, which can quantitatively investigate the energy transfer between hot anisotropic protons and EMIC waves, to burst-mode data obtained by the four MMS spacecraft. The energy transfer near the cyclotron resonance velocity was identified in the vicinity of the center of troughs of magnetic field intensity, which corresponds to the maxima of ion pressure in the compressional ULF wave. This result is consistent with the idea that the EMIC wave generation is modulated by ULF waves, and preferential locations for the cyclotron resonant energy transfer are the troughs of magnetic field intensity. In these troughs, relatively low resonance velocity due to the lower magnetic field intensity and the enhanced hot proton flux likely contribute to the enhanced energy transfer from hot protons to the EMIC waves by cyclotron resonance. Due to the compressional ULF wave, regions of the cyclotron resonant energy transfer can be narrow (only a few times of the gyroradii of hot resonant protons) in magnetic local time.

Published
2021

7. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E, Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

Published
2020
Full Text
View/download PDF

8. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E, Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

Published
2020
Full Text
View/download PDF

9. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E, Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

Published
2020
Full Text
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10. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E, Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

Published
2020
Full Text
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11. Investigating Mercury's Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J. -E, Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dosa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., Andre, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, Michiko, Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K. -H, Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quemerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J. -E

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury's environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

Published
2020
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12. Reimei observation of highly structured auroras caused by nonaccelerated electrons

Author

海老原, 祐輔, 坂野井, 健, 淺村, 和史, 平原, 聖文, Thomsen, M. F., Ebihara, Y., Sakanoi, T., Asamura, Kazushi, Hirahara, M., 海老原, 祐輔, 坂野井, 健, 淺村, 和史, 平原, 聖文, Thomsen, M. F., Ebihara, Y., Sakanoi, T., Asamura, Kazushi, and Hirahara, M.

Abstract

Accepted: 2010-04-16

Published
2015

13. ERG - A small-satellite mission to investigate the dynamics of the inner magnetosphere

Author

塩川, 和夫, Shiokawa, K., 関, 華奈子, Seki, K., 三好, 由純, Miyoshi, Y., 家田, 章正, Ieda, A., 小野, 高幸, Ono, T., 飯島, 雅英, Iizima, M., 長妻, 努, Nagatsuma, T., 小原, 隆博, Obara, T., 高島, 健, Takashima, Takeshi, 浅村, 和史, Asamura, Kazushi, 笠羽, 康正, Kasaba, Yasumasa, 松岡, 彩子, Matsuoka, Ayako, 齋藤, 義文, Saito, Yoshifumi, 齋藤, 宏文, Saito, Hirobumi, 平原, 聖文, Hirahara, M., 利根川, 豊, Tonegawa, Y., 遠山, 文雄, Toyama, F., 田中, 真, Tanaka, M., 能勢, 正仁, Nose, M., 笠原, 禎也, Kasahara, Y., 湯元, 清文, Yumoto, K., 河野, 英昭, Kawano, H., 吉川, 顕正, Yoshikawa, A., 海老原, 祐輔, Ebihara, Y., 行松, 彰, Yukimatsu, A., 佐藤, 夏雄, Sato, N., Watanabe, S., Inner Magnetosphere Subgroup in the Society of Geomagnetism and Earth, Planetary and Space Sciences, 塩川, 和夫, Shiokawa, K., 関, 華奈子, Seki, K., 三好, 由純, Miyoshi, Y., 家田, 章正, Ieda, A., 小野, 高幸, Ono, T., 飯島, 雅英, Iizima, M., 長妻, 努, Nagatsuma, T., 小原, 隆博, Obara, T., 高島, 健, Takashima, Takeshi, 浅村, 和史, Asamura, Kazushi, 笠羽, 康正, Kasaba, Yasumasa, 松岡, 彩子, Matsuoka, Ayako, 齋藤, 義文, Saito, Yoshifumi, 齋藤, 宏文, Saito, Hirobumi, 平原, 聖文, Hirahara, M., 利根川, 豊, Tonegawa, Y., 遠山, 文雄, Toyama, F., 田中, 真, Tanaka, M., 能勢, 正仁, Nose, M., 笠原, 禎也, Kasahara, Y., 湯元, 清文, Yumoto, K., 河野, 英昭, Kawano, H., 吉川, 顕正, Yoshikawa, A., 海老原, 祐輔, Ebihara, Y., 行松, 彰, Yukimatsu, A., 佐藤, 夏雄, Sato, N., Watanabe, S., and Inner Magnetosphere Subgroup in the Society of Geomagnetism and Earth, Planetary and Space Sciences

Abstract

著者人数：27名

Published
2015

15. The energization and radiation in geospace (ERG) project

Author

Miyoshi, Y., Ono, T., Takashima, T., Asamura, K., Hirahara, M., Kasaba, Y., Matsuoka, A., Kojima, H., Shiokawa, K., Seki, K., Fujimoto, M., Nagatsuma, T., Cheng, C. Z., Kazama, Y., Kasahara, S., Mitani, T., Matsumoto, H., Higashio, N., Kumamoto, A., Yagitani, S., Kasahara, Y., Ishisaka, K., Blomberg, Lars, Fujimoto, A., Katoh, Y., Ebihara, Y., Omura, Y., Nosé, M., Hori, T., Miyashita, Y., Tanaka, Y. -M, Segawa, T., Miyoshi, Y., Ono, T., Takashima, T., Asamura, K., Hirahara, M., Kasaba, Y., Matsuoka, A., Kojima, H., Shiokawa, K., Seki, K., Fujimoto, M., Nagatsuma, T., Cheng, C. Z., Kazama, Y., Kasahara, S., Mitani, T., Matsumoto, H., Higashio, N., Kumamoto, A., Yagitani, S., Kasahara, Y., Ishisaka, K., Blomberg, Lars, Fujimoto, A., Katoh, Y., Ebihara, Y., Omura, Y., Nosé, M., Hori, T., Miyashita, Y., Tanaka, Y. -M, and Segawa, T.

Abstract

The Energization and Radiation in Geospace (ERG) project for solar cycle 24 will explore how relativistic electrons in the radiation belts are generated during space storms. This geospace exploration project consists of three research teams: the ERG satellite observation team, the ground-based network observation team, and the integrated data analysis/simulation team. Satellite observation will provide in situ measurements of features such as the plasma distribution function, electric and magnetic fields, and plasma waves, whereas remote sensing by ground-based observations using, for example, HF radars, magnetometers, optical instruments, and radio wave receivers will provide the global state of the geospace. Various kinds of data will be integrated and compared with numerical simulations for quantitative understanding. Such a synergetic approach is essential for comprehensive understanding of relativistic electron generation/loss processes through crossenergy and cross-regional coupling in which different plasma populations and regions are dynamically coupled with each other. In addition, the ERG satellite will utilize a new and innovative measurement technique for wave-particle interactions that can directly measure the energy exchange process between particles and plasma waves. In this paper, we briefly review some of the profound problems regarding relativistic electron accelerations and losses that will be solved by the ERG project, and we provide an overview of the project., QC 20150306

Published
2012
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16. Spatial characteristics of wave-like structures in diffuse aurora obtained using optical observations

Author

Axelsson, K., Sergienko, T., Nilsson, H., Brandstrom, U., Ebihara, Y., Asamura, K., Hirahara, M., Axelsson, K., Sergienko, T., Nilsson, H., Brandstrom, U., Ebihara, Y., Asamura, K., and Hirahara, M.

Abstract

We present the results of a statistical study using optical images from ALIS (Auroral Large Imaging System) to investigate the spatial and temporal variations of structures in diffuse aurora. Analysis of conjugate Reimei data shows that such fine structures are a result of modulation of high-energy precipitating electrons. Pitch angle diffusion into the loss cone due to interaction of whistler mode waves with plasma sheet electrons is the most feasible mechanism leading to high-energy electron precipitation. This suggests that the fine structure is an indication of modulations of the efficiency of the wave–particle interaction. The scale sizes and variations of these structures, mapped to the magnetosphere, can give us information about the characteristics of the modulating wave activity. We found the scale size of the auroral stripes and the spacing between them to be on average 13–14 km, which corresponds to 3–4 ion gyro radii for protons with an energy of 7 keV. The structures move southward with a speed close to zero in the plasma convection frame.

Published
2012

17. Small and meso-scale properties of a substorm onset auroral arc

Author

Frey, H. U., Amm, O., Chaston, C. C., Fu, S., Haerendel, G., Juusola, L., Karlsson, Tomas, Lanchester, B., Nakamura, R., Ostgaard, N., Sakanoi, T., Seran, E., Whiter, D., Weygand, J., Asamura, K., Hirahara, M., Frey, H. U., Amm, O., Chaston, C. C., Fu, S., Haerendel, G., Juusola, L., Karlsson, Tomas, Lanchester, B., Nakamura, R., Ostgaard, N., Sakanoi, T., Seran, E., Whiter, D., Weygand, J., Asamura, K., and Hirahara, M.

Abstract

We present small and meso-scale properties of a substorm onset arc observed simultaneously by the Reimei and THEMIS satellites together with ground-based observations by the THEMIS GBO system. The optical observations revealed the slow equatorward motion of the growth-phase arc and the development of a much brighter onset arc poleward of it. Both arcs showed the typical particle signature of electrostatic acceleration in an inverted-V structure together with a strong Alfven wave acceleration signature at the poleward edge of the onset arc. Two THEMIS spacecraft encountered earthward flow bursts around the times the expanding optical aurora reached their magnetic footprints in the ionosphere. The particle and field measurements allowed for the reconstruction of the field-aligned current system and the determination of plasma properties in the auroral source region. Auroral arc properties were extracted from the optical and particle measurements and were used to compare measured values to theoretical predictions of the electrodynamic model for the generation of auroral arcs. Good agreement could be reached for the meso-scale arc properties. A qualitative analysis of the internal structuring of the bright onset arc suggests the operation of the tearing instability which provides a 'rope-like' appearance due to advection of the current in the sheared flow across the arc. We also note that for the observed parameters ionospheric conductivity gradients due to electron precipitation will be unstable to the feedback instability in the ionospheric Alfven resonator that can drive structuring in luminosity over the range of scales observed., QC 20110324

Published
2010
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18. On the source of the polar wind in the polar topside ionosphere : First results from the EISCAT Svalbard radar

Author

Ogawa, Y., Häggström, I., Buchert, Stephan C., Oksavik, K., Nozawa, S., Hirahara, M., van Eyken, A. P., Aso, T., Fujii, R., Ogawa, Y., Häggström, I., Buchert, Stephan C., Oksavik, K., Nozawa, S., Hirahara, M., van Eyken, A. P., Aso, T., and Fujii, R.

Abstract

We present quantitative radar observations of both hydrogen ion (H+) and oxygen ion (O+) upflow in the topside polar ionosphere using measurements that were recently carried out with the EISCAT Svalbard Radar and the Reimei satellite. H+ upflow was clearly observed equatorward of the cusp above 500 km altitude. Within the cusp the H+ density was very low, and the upflow was dominated by O+ ions, but on closed field lines the H+ became the larger contributor to the upward flux above about 550 km. The total flux seemed to be conserved, and so below 550 km altitude O+ (with a small upward velocity of similar to 50 m s(-1)) appeared to determine the upward flux which was then maintained by H+! in the topside ionosphere. We also found that the H+ density in the topside polar ionosphere was several times higher than current predictions of ionospheric models like IRI2001.

Published
2009
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19. Ion-dispersion and rapid electron fluctuations in the cusp : a case study

Author

Lunde, J., Buchert, S. C., Ogawa, Y., Hirahara, M., Seki, K., Ebihara, Y., Sakanoi, T., Asamura, K., Okada, M., Raita, T., Haggstrom, I., Lunde, J., Buchert, S. C., Ogawa, Y., Hirahara, M., Seki, K., Ebihara, Y., Sakanoi, T., Asamura, K., Okada, M., Raita, T., and Haggstrom, I.

Abstract

We present results from co-ordinated measurements with the low altitude REIMEI satellite and the ESR (EISCAT Svalbard Radar), together with other ground-based instruments carried out in February 2006. The results mainly relate to the dayside cusp where clear signatures of so-called ion-dispersion are seen in the satellite data. The cusp ion-dispersion is important for helping to understand the temporal and spatial structure of magnetopause reconnection. Whenever a satellite crosses boundaries of flux tubes or convection cells, cusp structures such as ion-dispersion will always be encountered. In our case we observed 3 distinct steps in the ion energy, but it includes at least 2 more steps as well, which we interpret as temporal features in relation to pulsed reconnection at the magnetopause. In addition, fast variations of the electron flux and energy occurring during these events have been studied in detail. The variations of the electron population, if interpreted as structures crossed by the REIMEI satellite, would map near the magnetopause to similar features as observed previously with the Cluster satellites. These were explained as Alfven waves originating from an X-line of magnetic reconnection.

Published
2008

20. Coordinated EISCAT Svalbard radar and Reimei satellite observations of ion upflows and suprathermal ions

Author

Ogawa, Y., Seki, K., Hirahara, M., Asamura, K., Sakanoi, T., Buchert, Stephan, Ebihara, Y., Obuchi, Y., Yamazaki, A., Sandahl, I., Nozawa, S., Fujii, R., Ogawa, Y., Seki, K., Hirahara, M., Asamura, K., Sakanoi, T., Buchert, Stephan, Ebihara, Y., Obuchi, Y., Yamazaki, A., Sandahl, I., Nozawa, S., and Fujii, R.

Abstract

The relationship between bulk ion upflows and suprathermal ions was investigated using data simultaneously obtained from the European Incoherent Scatter (EISCAT) Svalbard radar (ESR) and the Reimei satellite. Simultaneous observations were conducted in November 2005 and August 2006, and 14 conjunction data sets have been obtained at approximately 630 km in the dayside ionosphere. Suprathermal ions with energies of a few eV were present in the dayside cusp region, and the ion velocity distribution changed from an isotropic Maxwellian near the cusp region to tail heating at energies above a few eV in the cusp region. The velocity distribution of the suprathermal ions has a peak perpendicular or oblique to the geomagnetic field, and the temperature of the suprathermal ions was 0.9-1.4 eV. An increase in the phase space density (PSD) of the suprathermal ions, measured with the Reimei, was correlated with bulk ion upflow observed at the same altitude using EISCAT, and with the energy flux of precipitating electrons with energies of 50-500 eV. The PSD also has a good correlation with the electron temperature, which was increased by precipitation, but not with the ion temperature (0.1-0.3 eV) at the same altitude measured with EISCAT. These results suggest that plasma waves such as broadband extremely low frequency (BBELF) wavefields associated with precipitation are connected to the bulk ion upflows in the cusp and effectively cause the heating of suprathermal ions. The heating of suprathermal ions disagrees with anisotropic heating due to O+-O resonant charge exchange.

Published
2008
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21. Cold ions in the hot plasma sheet of Earth's magnetotail

Author

Seki, K, Hirahara, M, Hoshino, M, Terasawa, T, Elphic, RC, Saito, Y, Mukai, T, Hayakawa, H, Kojima, H, Matsumoto, H, Seki, K, Hirahara, M, Hoshino, M, Terasawa, T, Elphic, RC, Saito, Y, Mukai, T, Hayakawa, H, Kojima, H, and Matsumoto, H

Published
2003

22. Cold ions in the hot plasma sheet of Earth's magnetotail

Author

10215254, 00026139, Seki, K, Hirahara, M, Hoshino, M, Terasawa, T, Elphic, RC, Saito, Y, Mukai, T, Hayakawa, H, Kojima, H, Matsumoto, H, 10215254, 00026139, Seki, K, Hirahara, M, Hoshino, M, Terasawa, T, Elphic, RC, Saito, Y, Mukai, T, Hayakawa, H, Kojima, H, and Matsumoto, H

Published
2003

23. Investigating Mercury’s Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K.-H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J.-E., Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K.-H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J.-E.

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury’s environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

24. Investigating Mercury’s Environment with the Two-Spacecraft BepiColombo Mission

Author

Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K.-H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., Wahlund, J.-E., Milillo, A., Fujimoto, M., Murakami, G., Benkhoff, J., Zender, J., Aizawa, S., Dósa, M., Griton, L., Heyner, D., Ho, G., Imber, S. M., Jia, X., Karlsson, T., Killen, R. M., Laurenza, M., Lindsay, S. T., McKenna-Lawlor, S., Mura, A., Raines, J. M., Rothery, D. A., André, N., Baumjohann, W., Berezhnoy, A., Bourdin, P. A., Bunce, E. J., Califano, F., Deca, J., de la Fuente, S., Dong, C., Grava, C., Fatemi, S., Henri, P., Ivanovski, S. L., Jackson, B. V., James, M., Kallio, E., Kasaba, Y., Kilpua, E., Kobayashi, M., Langlais, B., Leblanc, F., Lhotka, C., Mangano, V., Martindale, A., Massetti, S., Masters, A., Morooka, M., Narita, Y., Oliveira, J. S., Odstrcil, D., Orsini, S., Pelizzo, M. G., Plainaki, C., Plaschke, F., Sahraoui, F., Seki, K., Slavin, J. A., Vainio, R., Wurz, P., Barabash, S., Carr, C. M., Delcourt, D., Glassmeier, K.-H., Grande, M., Hirahara, M., Huovelin, J., Korablev, O., Kojima, H., Lichtenegger, H., Livi, S., Matsuoka, A., Moissl, R., Moncuquet, M., Muinonen, K., Quèmerais, E., Saito, Y., Yagitani, S., Yoshikawa, I., and Wahlund, J.-E.

Abstract

The ESA-JAXA BepiColombo mission will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric dynamics at Mercury as well as their interactions with the solar wind, radiation, and interplanetary dust. Many scientific instruments onboard the two spacecraft will be completely, or partially devoted to study the near-space environment of Mercury as well as the complex processes that govern it. Many issues remain unsolved even after the MESSENGER mission that ended in 2015. The specific orbits of the two spacecraft, MPO and Mio, and the comprehensive scientific payload allow a wider range of scientific questions to be addressed than those that could be achieved by the individual instruments acting alone, or by previous missions. These joint observations are of key importance because many phenomena in Mercury’s environment are highly temporally and spatially variable. Examples of possible coordinated observations are described in this article, analysing the required geometrical conditions, pointing, resolutions and operation timing of different BepiColombo instruments sensors.

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