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1. Planetary space weather: scientific aspects and future perspectives

Author

Plainaki Christina, Lilensten Jean, Radioti Aikaterini, Andriopoulou Maria, Milillo Anna, Nordheim Tom A., Dandouras Iannis, Coustenis Athena, Grassi Davide, Mangano Valeria, Massetti Stefano, Orsini Stefano, and Lucchetti Alice

Subjects
Space weather, Planetary atmospheres, Planetary magnetospheres, Exospheres, Interactions, Comparative planetology, Future missions, JUICE, BEPI COLOMBO, Meteorology. Climatology, QC851-999
Abstract

In this paper, we review the scientific aspects of planetary space weather at different regions of our Solar System, performing a comparative planetology analysis that includes a direct reference to the circum-terrestrial case. Through an interdisciplinary analysis of existing results based both on observational data and theoretical models, we review the nature of the interactions between the environment of a Solar System body other than the Earth and the impinging plasma/radiation, and we offer some considerations related to the planning of future space observations. We highlight the importance of such comparative studies for data interpretations in the context of future space missions (e.g. ESA JUICE; ESA/JAXA BEPI COLOMBO). Moreover, we discuss how the study of planetary space weather can provide feedback for better understanding the traditional circum-terrestrial space weather. Finally, a strategy for future global investigations related to this thematic is proposed.

Published
2016
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2. Saturn northern aurorae at solstice from HST observations coordinated with Cassini Grand Finale

Author

Lamy, L., Prangé, R., Tao, C., Kim, T., Badman, S. V., Zarka, P., Cecconi, B., Kurth, W. S., Pryor, W., Bunce, E., and Radioti, A.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

Throughout 2017, the Hubble Space Telescope (HST) observed the northern far-ultraviolet aurorae of Saturn at northern solstice, during the Cassini Grand Finale. These conditions provided a complete viewing of the northern auroral region from Earth and a maximal solar illumination, expected to maximize the ionosphere-magnetosphere coupling. In this study, we analyze 24 HST images concurrently with Cassini measurements of Saturn's Kilometric Radiation and solar wind parameters predicted by two MHD models. The aurorae reveal highly variable components, down to timescales of minutes, radiating 7 to 124 +/-11 GW. They include a nightside-shifted main oval, unexpectedly frequent and bright cusp emissions and a dayside low latitude oval. On average, these emissions display a strong Local Time dependence with two maxima at dawn and pre-midnight, the latter being newly observed and attributed to nightside injections possibly associated with solstice conditions. These results provide a reference frame to analyze Cassini in situ measurements, whether simultaneous or not.

Published
2018
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3. Periodic shearing motions in the Jovian magnetosphere causing a localized peak in the main auroral emission close to noon

Author

Chané, E., Palmaerts, B., and Radioti, A.

Subjects
Physics - Space Physics
Abstract

Recently, a transient localized brightness enhancement has been observed in Jupiter's main auroral emission close to noon by Palmaerts et al. (2014). We use results from three-dimensional global MHD simulations to understand what is causing this localized peak in the main emission. In the simulations, the peak occurs every rotation period and is due to shearing motions in the magnetodisk. These shearing motions are caused by heavy flux-tubes being accelerated to large azimuthal speeds at dawn. The centrifugal force acting on these flux-tubes is then so high that they rapidly move away from the planet. When they reach noon, their azimuthal velocity decreases, thus reducing the centrifugal force, and allowing the flux-tubes to move back closer to Jupiter. The shearing motions associated with this periodic phenomenon locally increase the field aligned currents in the simulations, thus causing a transient brightness enhancement in the main auroral emission, similar to the one observed by Palmaerts et al. (2014)., Comment: accepted for publication on 2018/04/25 by Planetary and Space Science

Published
2018
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4. Corotating Magnetic Reconnection Site in Saturn's Magnetosphere

Author

Yao, Zhonghua, Coates, A. J., Ray, L. C., Rae, I. J., Grodent, D., Jones, G. H., Dougherty, M. K., Owen, C. J., Guo, R. L., Dunn, W., Radioti, A., Pu, Z. Y., Lewis, G. R., Waite, J. H., and Gerard, J. -C.

Subjects
Physics - Space Physics
Abstract

Using measurements from the Cassini spacecraft in Saturn's magnetosphere, we propose a 3D physical picture of a corotating reconnection site, which can only be driven by an internally generated source. Our results demonstrate that the corotating magnetic reconnection can drive an expansion of the current sheet in Saturn's magnetosphere and, consequently, can produce Fermi acceleration of electrons. This reconnection site lasted for longer than one of Saturn's rotation period. The long-lasting and corotating natures of the magnetic reconnection site at Saturn suggest fundamentally different roles of magnetic reconnection in driving magnetospheric dynamics (e.g., the auroral precipitation) from the Earth. Our corotating reconnection picture could also potentially shed light on the fast rotating magnetized plasma environments in the solar system and beyond., Comment: 7 pages, 5 figures

Published
2017
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5. Cassini in situ observations of long-duration magnetic reconnection in Saturn's magnetotail

Author

Arridge, Christopher S., Eastwood, Jonathan P., Jackman, Caitriona M., Poh, Gang-Kai, Slavin, James A., Thomsen, Michelle F., André, Nicolas, Jia, Xianzhe, Kidder, Ariah, Lamy, Laurent, Radioti, Aikaterina, Reisenfeld, Dan B., Sergis, Nick, Volwerk, Martin, Walsh, Andrew P., Zarka, Philippe, Coates, Andrew J., and Dougherty, Michele K.

Subjects
Astrophysics - Earth and Planetary Astrophysics, Physics - Space Physics
Abstract

Magnetic reconnection is a fundamental process in solar system and astrophysical plasmas, through which stored magnetic energy associated with current sheets is converted into thermal, kinetic and wave energy. Magnetic reconnection is also thought to be a key process involved in shedding internally produced plasma from the giant magnetospheres at Jupiter and Saturn through topological reconfiguration of the magnetic field. The region where magnetic fields reconnect is known as the diffusion region and in this letter we report on the first encounter of the Cassini spacecraft with a diffusion region in Saturn's magnetotail. The data also show evidence of magnetic reconnection over a period of 19 h revealing that reconnection can, in fact, act for prolonged intervals in a rapidly rotating magnetosphere. We show that reconnection can be a significant pathway for internal plasma loss at Saturn. This counters the view of reconnection as a transient method of internal plasma loss at Saturn. These results, although directly relating to the magnetosphere of Saturn, have applications in the understanding of other rapidly rotating magnetospheres, including that of Jupiter and other astrophysical bodies., Comment: Initially submitted version (submitted 24 March 2015), published online in Nature Physics 30 November 2015

Published
2015
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6. The EChO science case

Author

Tinetti, Giovanna, Drossart, Pierre, Eccleston, Paul, Hartogh, Paul, Isaak, Kate, Linder, Martin, Lovis, Christophe, Micela, Giusi, Ollivier, Marc, Puig, Ludovic, Ribas, Ignasi, Snellen, Ignas, Allard, Bruce Swinyard. France, Barstow, Joanna, Cho, James, Coustenis, Athena, Cockell, Charles, Correia, Alexandre, Decin, Leen, de Kok, Remco, Deroo, Pieter, Encrenaz, Therese, Forget, Francois, Glasse, Alistair, Griffith, Caitlin, Guillot, Tristan, Koskinen, Tommi, Lammer, Helmut, Leconte, Jeremy, Maxted, Pierre, Mueller-Wodarg, Ingo, Nelson, Richard, North, Chris, Pallé, Enric, Pagano, Isabella, Piccioni, Guseppe, Pinfield, David, Selsis, Franck, Sozzetti, Alessandro, Stixrude, Lars, Tennyson, Jonathan, Turrini, Diego, Beaulieu, Mariarosa Zapatero-Osorio. Jean-Philippe, Grodent, Denis, Guedel, Manuel, Luz, David, Nørgaard-Nielsen, Hans Ulrik, Ray, Tom, Rickman, Hans, Selig, Avri, Banaszkiewicz, Mark Swain. Marek, Barlow, Mike, Bowles, Neil, Branduardi-Raymont, Graziella, Foresto, Vincent Coudé du, Gerard, Jean-Claude, Gizon, Laurent, Hornstrup, Allan, Jarchow, Christopher, Kerschbaum, Franz, Kovacs, Géza, Lagage, Pierre-Olivier, Lim, Tanya, Lopez-Morales, Mercedes, Malaguti, Giuseppe, Pace, Emanuele, Pascale, Enzo, Vandenbussche, Bart, Wright, Gillian, Adriani, Gonzalo Ramos Zapata. Alberto, Azzollini, Ruymán, Balado, Ana, Bryson, Ian, Burston, Raymond, Colomé, Josep, Crook, Martin, Di Giorgio, Anna, Griffin, Matt, Hoogeveen, Ruud, Ottensamer, Roland, Irshad, Ranah, Middleton, Kevin, Morgante, Gianluca, Pinsard, Frederic, Rataj, Mirek, Reess, Jean-Michel, Savini, Giorgio, Schrader, Jan-Rutger, Stamper, Richard, Abe, Berend Winter. L., Abreu, M., Achilleos, N., Ade, P., Adybekian, V., Affer, L., Agnor, C., Agundez, M., Alard, C., Alcala, J., Prieto, C. Allende, Floriano, F. J. Alonso, Altieri, F., Iglesias, C. A. Alvarez, Amado, P., Andersen, A., Aylward, A., Baffa, C., Bakos, G., Ballerini, P., Banaszkiewicz, M., Barber, R. J., Barrado, D., Barton, E. J., Batista, V., Bellucci, G., Avilés, J. A. Belmonte, Berry, D., Bézard, B., Biondi, D., Błęcka, M., Boisse, I., Bonfond, B., Bordé, P., Börner, P., Bouy, H., Brown, L., Buchhave, L., Budaj, J., Bulgarelli, A., Burleigh, M., Cabral, A., Capria, M. T., Cassan, A., Cavarroc, C., Cecchi-Pestellini, C., Cerulli, R., Chadney, J., Chamberlain, S., Charnoz, S., Jessen, N. Christian, Ciaravella, A., Claret, A., Claudi, R., Coates, A., Cole, R., Collura, A., Cordier, D., Covino, E., Danielski, C., Damasso, M., Deeg, H. J., Delgado-Mena, E., Del Vecchio, C., Demangeon, O., De Sio, A., De Wit, J., Dobrijévic, M., Doel, P., Dominic, C., Dorfi, E., Eales, S., Eiroa, C., Contreras, M. Espinoza, Esposito, M., Eymet, V., Fabrizio, N., Fernández, M., Castella, B. Femenía, Figueira, P., Filacchione, G., Fletcher, L., Focardi, M., Fossey, S., Fouqué, P., Frith, J., Galand, M., Gambicorti, L., Gaulme, P., López, R. J. García, Garcia-Piquer, A., Gear, W., Gerard, J. -C., Gesa, L., Giani, E., Gianotti, F., Gillon, M., Giro, E., Giuranna, M., Gomez, H., Gomez-Leal, I., Hernandez, J. Gonzalez, Merino, B. González, Graczyk, R., Grassi, D., Guardia, J., Guio, P., Gustin, J., Hargrave, P., Haigh, J., Hébrard, E., Heiter, U., Heredero, R. L., Herrero, E., Hersant, F., Heyrovsky, D., Hollis, M., Hubert, B., Hueso, R., Israelian, G., Iro, N., Irwin, P., Jacquemoud, S., Jones, G., Jones, H., Justtanont, K., Kehoe, T., Kerschbaum, F., Kerins, E., Kervella, P., Kipping, D., Koskinen, T., Krupp, N., Lahav, O., Laken, B., Lanza, N., Lellouch, E., Leto, G., Goldaracena, J. Licandro, Lithgow-Bertelloni, C., Liu, S. J., Cicero, U. Lo, Lodieu, N., Lognonné, P., Lopez-Puertas, M., Lopez-Valverde, M. A., Rasmussen, I. Lundgaard, Luntzer, A., Machado, P., MacTavish, C., Maggio, A., Maillard, J. -P., Magnes, W., Maldonado, J., Mall, U., Marquette, J. -B., Mauskopf, P., Massi, F., Maurin, A. -S., Medvedev, A., Michaut, C., Miles-Paez, P., Montalto, M., Rodríguez, P. Montañés, Monteiro, M., Montes, D., Morais, H., Morales, J. C., Morales-Calderón, M., Morello, G., Martín, A. Moro, Moses, J., Bedon, A. Moya, Alcaino, F. Murgas, Oliva, E., Orton, G., Palla, F., Pancrazzi, M., Pantin, E., Parmentier, V., Parviainen, H., Ramírez, K. Y. Peña, Peralta, J., Perez-Hoyos, S., Petrov, R., Pezzuto, S., Pietrzak, R., Pilat-Lohinger, E., Piskunov, N., Prinja, R., Prisinzano, L., Polichtchouk, I., Poretti, E., Radioti, A., Ramos, A. A., Rank-Lüftinger, T., Read, P., Readorn, K., López, R. Rebolo, Rebordão, J., Rengel, M., Rezac, L., Rocchetto, M., Rodler, F., Béjar, V. J. Sánchez, Lavega, A. Sanchez, Sanromá, E., Santos, N., Forcada, J. Sanz, Scandariato, G., Schmider, F. -X., Scholz, A., Scuderi, S., Sethenadh, J., Shore, S., Showman, A., Sicardy, B., Sitek, P., Smith, A., Soret, L., Sousa, S., Stiepen, A., Stolarski, M., Strazzulla, G., Tabernero, H. M, Tanga, P., Tecsa, M., Temple, J., Terenzi, L., Tessenyi, M., Testi, L., Thompson, S., Thrastarson, H., Tingley, B. W., Trifoglio, M., Torres, J. Martín, Tozzi, A., Turrini, D., Varley, R., Vakili, F., de Val-Borro, M., Valdivieso, M. L., Venot, O., Villaver, E., Vinatier, S., Viti, S., Waldmann, I., Waltham, D., Ward-Thompson, D., Waters, R., Watkins, C., Watson, D., Wawer, P., Wawrzaszk, A., White, G., Widemann, T., Winek, W., Wiśniowski, T., Yelle, R., Yung, Y., and Yurchenko, S. N.

Subjects
Astrophysics - Earth and Planetary Astrophysics
Abstract

The discovery of almost 2000 exoplanets has revealed an unexpectedly diverse planet population. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? What causes the exceptional diversity observed as compared to the Solar System? EChO (Exoplanet Characterisation Observatory) has been designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large and diverse planet sample within its four-year mission lifetime. EChO can target the atmospheres of super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300K-3000K) of F to M-type host stars. Over the next ten years, several new ground- and space-based transit surveys will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO's launch and enable the atmospheric characterisation of hundreds of planets. Placing the satellite at L2 provides a cold and stable thermal environment, as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. A 1m class telescope is sufficiently large to achieve the necessary spectro-photometric precision. The spectral coverage (0.5-11 micron, goal 16 micron) and SNR to be achieved by EChO, thanks to its high stability and dedicated design, would enable a very accurate measurement of the atmospheric composition and structure of hundreds of exoplanets., Comment: 50 pages, 30 figures. Experimental Astronomy

Published
2015
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12. A chemical survey of exoplanets with ARIEL

Author

Tinetti, Giovanna, Drossart, Pierre, Eccleston, Paul, Hartogh, Paul, Heske, Astrid, Leconte, Jérémy, Micela, Giusi, Ollivier, Marc, Pilbratt, Göran, Puig, Ludovic, Turrini, Diego, Vandenbussche, Bart, Wolkenberg, Paulina, Beaulieu, Jean-Philippe, Buchave, Lars A., Ferus, Martin, Griffin, Matt, Guedel, Manuel, Justtanont, Kay, Lagage, Pierre-Olivier, Machado, Pedro, Malaguti, Giuseppe, Min, Michiel, Nørgaard-Nielsen, Hans Ulrik, Rataj, Mirek, Ray, Tom, Ribas, Ignasi, Swain, Mark, Szabo, Robert, Werner, Stephanie, Barstow, Joanna, Burleigh, Matt, Cho, James, du Foresto, Vincent Coudé, Coustenis, Athena, Decin, Leen, Encrenaz, Therese, Galand, Marina, Gillon, Michael, Helled, Ravit, Morales, Juan Carlos, Muñoz, Antonio García, Moneti, Andrea, Pagano, Isabella, Pascale, Enzo, Piccioni, Giuseppe, Pinfield, David, Sarkar, Subhajit, Selsis, Franck, Tennyson, Jonathan, Triaud, Amaury, Venot, Olivia, Waldmann, Ingo, Waltham, David, Wright, Gillian, Amiaux, Jerome, Auguères, Jean-Louis, Berthé, Michel, Bezawada, Naidu, Bishop, Georgia, Bowles, Neil, Coffey, Deirdre, Colomé, Josep, Crook, Martin, Crouzet, Pierre-Elie, Da Peppo, Vania, Sanz, Isabel Escudero, Focardi, Mauro, Frericks, Martin, Hunt, Tom, Kohley, Ralf, Middleton, Kevin, Morgante, Gianluca, Ottensamer, Roland, Pace, Emanuele, Pearson, Chris, Stamper, Richard, Symonds, Kate, Rengel, Miriam, Renotte, Etienne, Ade, Peter, Affer, Laura, Alard, Christophe, Allard, Nicole, Altieri, Francesca, André, Yves, Arena, Claudio, Argyriou, Ioannis, Aylward, Alan, Baccani, Cristian, Bakos, Gaspar, Banaszkiewicz, Marek, Barlow, Mike, Batista, Virginie, Bellucci, Giancarlo, Benatti, Serena, Bernardi, Pernelle, Bézard, Bruno, Blecka, Maria, Bolmont, Emeline, Bonfond, Bertrand, Bonito, Rosaria, Bonomo, Aldo S., Brucato, John Robert, Brun, Allan Sacha, Bryson, Ian, Bujwan, Waldemar, Casewell, Sarah, Charnay, Bejamin, Pestellini, Cesare Cecchi, Chen, Guo, Ciaravella, Angela, Claudi, Riccardo, Clédassou, Rodolphe, Damasso, Mario, Damiano, Mario, Danielski, Camilla, Deroo, Pieter, Di Giorgio, Anna Maria, Dominik, Carsten, Doublier, Vanessa, Doyle, Simon, Doyon, René, Drummond, Benjamin, Duong, Bastien, Eales, Stephen, Edwards, Billy, Farina, Maria, Flaccomio, Ettore, Fletcher, Leigh, Forget, François, Fossey, Steve, Fränz, Markus, Fujii, Yuka, García-Piquer, Álvaro, Gear, Walter, Geoffray, Hervé, Gérard, Jean Claude, Gesa, Lluis, Gomez, H., Graczyk, Rafał, Griffith, Caitlin, Grodent, Denis, Guarcello, Mario Giuseppe, Gustin, Jacques, Hamano, Keiko, Hargrave, Peter, Hello, Yann, Heng, Kevin, Herrero, Enrique, Hornstrup, Allan, Hubert, Benoit, Ida, Shigeru, Ikoma, Masahiro, Iro, Nicolas, Irwin, Patrick, Jarchow, Christopher, Jaubert, Jean, Jones, Hugh, Julien, Queyrel, Kameda, Shingo, Kerschbaum, Franz, Kervella, Pierre, Koskinen, Tommi, Krijger, Matthijs, Krupp, Norbert, Lafarga, Marina, Landini, Federico, Lellouch, Emanuel, Leto, Giuseppe, Luntzer, A., Rank-Lüftinger, Theresa, Maggio, Antonio, Maldonado, Jesus, Maillard, Jean-Pierre, Mall, Urs, Marquette, Jean-Baptiste, Mathis, Stephane, Maxted, Pierre, Matsuo, Taro, Medvedev, Alexander, Miguel, Yamila, Minier, Vincent, Morello, Giuseppe, Mura, Alessandro, Narita, Norio, Nascimbeni, Valerio, Nguyen Tong, N., Noce, Vladimiro, Oliva, Fabrizio, Palle, Enric, Palmer, Paul, Pancrazzi, Maurizio, Papageorgiou, Andreas, Parmentier, Vivien, Perger, Manuel, Petralia, Antonino, Pezzuto, Stefano, Pierrehumbert, Ray, Pillitteri, Ignazio, Piotto, Giampaolo, Pisano, Giampaolo, Prisinzano, Loredana, Radioti, Aikaterini, Réess, Jean-Michel, Rezac, Ladislav, Rocchetto, Marco, Rosich, Albert, Sanna, Nicoletta, Santerne, Alexandre, Savini, Giorgio, Scandariato, Gaetano, Sicardy, Bruno, Sierra, Carles, Sindoni, Giuseppe, Skup, Konrad, Snellen, Ignas, Sobiecki, Mateusz, Soret, Lauriane, Sozzetti, Alessandro, Stiepen, A., Strugarek, Antoine, Taylor, Jake, Taylor, William, Terenzi, Luca, Tessenyi, Marcell, Tsiaras, Angelos, Tucker, C., Valencia, Diana, Vasisht, Gautam, Vazan, Allona, Vilardell, Francesc, Vinatier, Sabrine, Viti, Serena, Waters, Rens, Wawer, Piotr, Wawrzaszek, Anna, Whitworth, Anthony, Yung, Yuk L., Yurchenko, Sergey N., Osorio, María Rosa Zapatero, Zellem, Robert, Zingales, Tiziano, and Zwart, Frans

Published
2018
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22. Jupiter's Aurora Observed With HST During Juno Orbits 3 to 7

Author

Denis Grodent, B. Bonfond, Z. Yao, J.‐C. Gérard, A. Radioti, M. Dumont, B. Palmaerts, A. Adriani, S. V. Badman, E. J. Bunce, J. T. Clarke, J. E. P. Connerney, G. R. Gladstone, T. Greathouse, T. Kimura, W. S. Kurth, B. H. Mauk, D. J. McComas, J. D. Nichols, G. S. Orton, L. Roth, J. Saur, and P. Valek

Published
2018
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23. Auroral streamer and its role in driving wave-like pre-onset aurora

Author

Zhonghua Yao, Z. Y. Pu, I. J. Rae, A. Radioti, and M. V. Kubyshkina

Subjects
Substorm Onset, Substorm Current Wedge, Planetary Magnetosphere, Auroral Breakup, Auroral Imager, Science, Geology, QE1-996.5
Abstract

Abstract The time scales of reconnection outflow, substorm expansion, and development of instabilities in the terrestrial magnetosphere are comparable, i.e., from several to tens of minutes, and their existence is related. In this paper, we investigate the physical relations among those phenomena with measurements during a substorm event on January 29, 2008. We present conjugate measurements from ground-based high-temporal resolution all-sky imagers and in situ THEMIS measurements. An auroral streamer (north–south aligned thin auroral layer) was formed and propagated equatorward, which usually implies an earthward propagating plasma flow in the magnetotail. At the most equatorward part of the auroral streamer, a wave-like auroral band was formed aligning in the east–west direction. The wave-like auroral structure is usually explained as a consequence of instability development. Using AM03 model, we trace the auroral structure to magnetotail and estimate a wavelength of ~0.5 R E. The scale is comparable to the drift mode wavelength determined by the in situ measurements from THEMIS-A, whose footpoint is on the wave-like auroral arc. We also present similar wave-like aurora observations from Cassini ultraviolet imaging spectrograph at Saturn and from Hubble space telescope at Jupiter, suggesting that the wave-like aurora structure is likely a result of fundamental plasma dynamics in the solar system planetary magnetospheres.

Published
2017
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33. The far-ultraviolet main auroral emission at Jupiter – Part 1: Dawn–dusk brightness asymmetries

Author

B. Bonfond, J. Gustin, J.-C. Gérard, D. Grodent, A. Radioti, B. Palmaerts, S. V. Badman, K. K. Khurana, and C. Tao

Subjects
Science, Physics, QC1-999, Geophysics. Cosmic physics, QC801-809
Abstract

The main auroral emission at Jupiter generally appears as a quasi-closed curtain centered around the magnetic pole. This auroral feature, which accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range, is related to corotation enforcement currents in the middle magnetosphere. Early models for these currents assumed axisymmetry, but significant local time variability is obvious on any image of the Jovian aurorae. Here we use far-UV images from the Hubble Space Telescope to further characterize these variations on a statistical basis. We show that the dusk side sector is ~ 3 times brighter than the dawn side in the southern hemisphere and ~ 1.1 brighter in the northern hemisphere, where the magnetic anomaly complicates the interpretation of the measurements. We suggest that such an asymmetry between the dawn and the dusk sectors could be the result of a partial ring current in the nightside magnetosphere.

Published
2015
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34. The far-ultraviolet main auroral emission at Jupiter – Part 2: Vertical emission profile

Author

B. Bonfond, J. Gustin, J.-C. Gérard, D. Grodent, A. Radioti, B. Palmaerts, S. V. Badman, K. K. Khurana, and C. Tao

Subjects
Science, Physics, QC1-999, Geophysics. Cosmic physics, QC801-809
Abstract

The aurorae at Jupiter are made up of many different features associated with a variety of generation mechanisms. The main auroral emission, also known as the main oval, is the most prominent of them as it accounts for approximately half of the total power emitted by the aurorae in the ultraviolet range. The energy of the precipitating electrons is a crucial parameter to characterize the processes at play which give rise to these auroral emissions, and the altitude of the emissions directly depends on this energy. Here we make use of far-UV (FUV) images acquired with the Advanced Camera for Surveys on board the Hubble Space Telescope and spectra acquired with the Space Telescope Imaging Spectrograph to measure the vertical profile of the main emissions. The altitude of the brightness peak as seen above the limb is ~ 400 km, which is significantly higher than the 250 km measured in the post-dusk sector by Galileo in the visible domain. However, a detailed analysis of the effect of hydrocarbon absorption, including both simulations and FUV spectral observations, indicates that FUV apparent vertical profiles should be considered with caution, as these observations are not incompatible with an emission peak located at 250 km. The analysis also calls for spectral observations to be carried out with an optimized geometry in order to remove observational ambiguities.

Published
2015
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36. Bar Code Events in the Juno-UVS Data: Signature ~10 MeV Electron Microbursts at Jupiter

Author

Bonfond, B, Gladstone, G. R, Grodent, D, Gerard, J.-C, Greathouse, T K, Hue, V, Kammer, J. A, Versteeg, M. H, Davis, M. W, Becker, H. N, Radioti, A, Elliott, S. S, Imai, M, Paranicas, C. P, Bolton, S. J, Levin, S. M, and Connerney, J. E. P

Subjects
Lunar And Planetary Science And Exploration
Abstract

One of the most intriguing discoveries of Juno is the quasi-systematic detection of upgoing electrons above the auroral regions. Here we discuss a by-product of the most energetic component of this population: a contamination resembling bar codes in the Juno-UVS images. This pattern is likely caused by bursts of ∼10 MeV electrons penetrating the instrument. These events are mostly detected when Juno’s magnetic footprint is located poleward of the main emission relative to the magnetic pole. The signal is not periodic, but the bursts are typically 0.1–1 s apart. They are essentially detected when Juno-UVS is oriented toward Jupiter, indicating that the signal is due to upgoing electrons. The event detections occur between 1 and 7 Jovian radii above the 1-bar level, suggesting that the electron acceleration takes place close to Jupiter and is thus both strong and brief.

Published
2018
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37. Towards a Global Unified Model of Europa’s Tenuous Atmosphere

Author

Plainaki, Christina, Cassidy, Tim A., Shematovich, Valery I., Milillo, Anna, Wurz, Peter, Vorburger, Audrey, Roth, Lorenz, Galli, André, Rubin, Martin, Blöcker, Aljona, Brandt, Pontus C., Crary, Frank, Dandouras, Iannis, Jia, Xianzhe, Grassi, Davide, Hartogh, Paul, Lucchetti, Alice, McGrath, Melissa, Mangano, Valeria, Mura, Alessandro, Orsini, Stefano, Paranicas, Chris, Radioti, Aikaterini, Retherford, Kurt D., Saur, Joachim, and Teolis, Ben

Published
2018
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41. Full-SiC derotator optics for METimage: flight hardware status

Author

Minoglou, Kyriaki, Karafolas, Nikos, Cugny, Bruno, Bastin, Christian, Renotte, Etienne, Bougoin, Michel, Bronlet, P., Carlomagno, B., Feutry, Alexis, Fontana, Nicolas, Gloesener, Pierre, Jago, A., Lemagne, Fabien, Logut, Daniel, Mallet, Florent, Martin, Y., Pfaffe, M., Radioti, A., and Thomas, S.

Published
2023
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48. The EChO science case

Author

Tinetti, Giovanna, primary, Drossart, Pierre, additional, Eccleston, Paul, additional, Hartogh, Paul, additional, Isaak, Kate, additional, Linder, Martin, additional, Lovis, Christophe, additional, Micela, Giusi, additional, Ollivier, Marc, additional, Puig, Ludovic, additional, Ribas, Ignasi, additional, Snellen, Ignas, additional, Swinyard, Bruce, additional, Allard, France, additional, Barstow, Joanna, additional, Cho, James, additional, Coustenis, Athena, additional, Cockell, Charles, additional, Correia, Alexandre, additional, Decin, Leen, additional, de Kok, Remco, additional, Deroo, Pieter, additional, Encrenaz, Therese, additional, Forget, Francois, additional, Glasse, Alistair, additional, Griffith, Caitlin, additional, Guillot, Tristan, additional, Koskinen, Tommi, additional, Lammer, Helmut, additional, Leconte, Jeremy, additional, Maxted, Pierre, additional, Mueller-Wodarg, Ingo, additional, Nelson, Richard, additional, North, Chris, additional, Pallé, Enric, additional, Pagano, Isabella, additional, Piccioni, Guseppe, additional, Pinfield, David, additional, Selsis, Franck, additional, Sozzetti, Alessandro, additional, Stixrude, Lars, additional, Tennyson, Jonathan, additional, Turrini, Diego, additional, Zapatero-Osorio, Mariarosa, additional, Beaulieu, Jean-Philippe, additional, Grodent, Denis, additional, Guedel, Manuel, additional, Luz, David, additional, Nørgaard-Nielsen, Hans Ulrik, additional, Ray, Tom, additional, Rickman, Hans, additional, Selig, Avri, additional, Swain, Mark, additional, Banaszkiewicz, Marek, additional, Barlow, Mike, additional, Bowles, Neil, additional, Branduardi-Raymont, Graziella, additional, du Foresto, Vincent Coudé, additional, Gerard, Jean-Claude, additional, Gizon, Laurent, additional, Hornstrup, Allan, additional, Jarchow, Christopher, additional, Kerschbaum, Franz, additional, Kovacs, Géza, additional, Lagage, Pierre-Olivier, additional, Lim, Tanya, additional, Lopez-Morales, Mercedes, additional, Malaguti, Giuseppe, additional, Pace, Emanuele, additional, Pascale, Enzo, additional, Vandenbussche, Bart, additional, Wright, Gillian, additional, Ramos Zapata, Gonzalo, additional, Adriani, Alberto, additional, Azzollini, Ruymán, additional, Balado, Ana, additional, Bryson, Ian, additional, Burston, Raymond, additional, Colomé, Josep, additional, Crook, Martin, additional, Di Giorgio, Anna, additional, Griffin, Matt, additional, Hoogeveen, Ruud, additional, Ottensamer, Roland, additional, Irshad, Ranah, additional, Middleton, Kevin, additional, Morgante, Gianluca, additional, Pinsard, Frederic, additional, Rataj, Mirek, additional, Reess, Jean-Michel, additional, Savini, Giorgio, additional, Schrader, Jan-Rutger, additional, Stamper, Richard, additional, Winter, Berend, additional, Abe, L., additional, Abreu, M., additional, Achilleos, N., additional, Ade, P., additional, Adybekian, V., additional, Affer, L., additional, Agnor, C., additional, Agundez, M., additional, Alard, C., additional, Alcala, J., additional, Prieto, C. Allende, additional, Alonso Floriano, F. J., additional, Altieri, F., additional, Alvarez Iglesias, C. A., additional, Amado, P., additional, Andersen, A., additional, Aylward, A., additional, Baffa, C., additional, Bakos, G., additional, Ballerini, P., additional, Banaszkiewicz, M., additional, Barber, R. J., additional, Barrado, D., additional, Barton, E. J., additional, Batista, V., additional, Bellucci, G., additional, Belmonte Avilés, J. A., additional, Berry, D., additional, Bézard, B., additional, Biondi, D., additional, Błęcka, M., additional, Boisse, I., additional, Bonfond, B., additional, Bordé, P., additional, Börner, P., additional, Bouy, H., additional, Brown, L., additional, Buchhave, L., additional, Budaj, J., additional, Bulgarelli, A., additional, Burleigh, M., additional, Cabral, A., additional, Capria, M. T., additional, Cassan, A., additional, Cavarroc, C., additional, Cecchi-Pestellini, C., additional, Cerulli, R., additional, Chadney, J., additional, Chamberlain, S., additional, Christian Jessen, N., additional, Ciaravella, A., additional, Claret, A., additional, Claudi, R., additional, Coates, A., additional, Cole, R., additional, Collur, A., additional, Cordier, D., additional, Covino, E., additional, Danielski, C., additional, Damasso, M., additional, Deeg, H. J., additional, Delgado-Mena, E., additional, Del Vecchio, C., additional, Demangeon, O., additional, De Sio, A., additional, De Wit, J., additional, Dobrijévi, M., additional, Doel, P., additional, Dominic, C., additional, Dorfi, E., additional, Eales, S., additional, Eiroa, C., additional, Espinoza Contreras, M., additional, Esposito, M., additional, Eymet, V., additional, Fabrizio, N., additional, Fernández, M., additional, Femenía Castella, B., additional, Figueira, P., additional, Filacchione, G., additional, Fletcher, L., additional, Focardi, M., additional, Fossey, S., additional, Fouqué, P., additional, Frith, J., additional, Galand, M., additional, Gambicorti, L., additional, Gaulme, P., additional, García López, R. J., additional, Garcia-Piquer, A., additional, Gear, W., additional, Gerard, J. -C., additional, Gesa, L., additional, Giani, E., additional, Gianotti, F., additional, Gillon, M., additional, Giro, E., additional, Giuranna, M., additional, Gomez, H., additional, Gomez-Leal, I., additional, Gonzalez Hernandez, J., additional, GonzÁlez Merino, B., additional, Graczyk, R., additional, Grassi, D., additional, Guardia, J., additional, Guio, P., additional, Gustin, J., additional, Hargrave, P., additional, Haigh, J., additional, Hébrard, E., additional, Heiter, U., additional, Heredero, R. L., additional, Herrero, E., additional, Hersant, F., additional, Heyrovsky, D., additional, Hollis, M., additional, Hubert, B., additional, Hueso, R., additional, Israelian, G., additional, Iro, N., additional, Irwin, P., additional, Jacquemoud, S., additional, Jones, G., additional, Jones, H., additional, Justtanont, K., additional, Kehoe, T., additional, Kerschbaum, F., additional, Kerins, E., additional, Kervell, P., additional, Kipping, D., additional, Koskinen, T., additional, Krupp, N., additional, Lahav, O., additional, Laken, B., additional, Lanza, N., additional, Lellouch, E., additional, Leto, G., additional, Goldaracena, J. Licandro, additional, Bertelloni, C. Lithgow, additional, Liu, S. J., additional, Cicero, U. Lo, additional, Lodieu, N., additional, Lognonné, P., additional, Puertas, M. Lopez, additional, Valverde, M. A. Lopez, additional, Rasmussen, I. Lundgaard, additional, Luntzer, A., additional, Machado, P., additional, Tavish, C. Mac, additional, Maggio, A., additional, Maillard, J. P., additional, Magnes, W., additional, Maldonado, J., additional, Mall, U., additional, Marquette, J. B., additional, Mauskopf, P., additional, Massi, F., additional, Maurin, A. S., additional, Medvedev, A., additional, Michaut, C., additional, Paez, P. Miles, additional, Montalto, M., additional, Rodríguez, P. Montañés, additional, Monteiro, M., additional, Montes, D., additional, Morais, H., additional, Morale, J. C., additional, Morales-Calderón, M., additional, Morello, G., additional, Martín, A. Moro, additional, Moses, J., additional, Bedon, A. Moya, additional, Alcaino, F. Murgas, additional, Oliva, E., additional, Orton, G., additional, Palla, F., additional, Pancrazzi, M., additional, Pantin, E., additional, Parmentier, V., additional, Parviainen, H., additional, Ramirez, Y. Pena, additional, Peralta, J., additional, Perez-Hoyos, S., additional, Petrov, R., additional, Pezzuto, S., additional, Pietrzak, R., additional, Pilat-Lohinger, E., additional, Piskunov, N., additional, Prinja, R., additional, Prisinzano, L., additional, Polichtchouk, I., additional, Poretti, E., additional, Radioti, A., additional, Ramos, A., additional, Rank-Luftinger, T., additional, Read, P., additional, Readorn, K., additional, Lopez, R. Rebolo, additional, Rebordao, J., additional, Rengel, M., additional, Rezac, L., additional, Rocchetto, M., additional, Rodler, F., additional, Bejar, J. Sanchez, additional, Sanchez Lavega, A., additional, Sanroma, E., additional, Santos, N., additional, Forcada, J. Sanz, additional, Scandariato, G., additional, Schmider, F.- X., additional, Scholz, A., additional, Scuderi, S., additional, Sethenadh, J., additional, Shore, S., additional, Showman, A., additional, Sicardy, B., additional, Sitek, P., additional, Smith, A., additional, Soret, L., additional, Sousa, S., additional, Stiepen, A., additional, Stolarski, M., additional, Strazzulla, G., additional, Tabernero, H. M., additional, Tanga, P., additional, Tecsa, M., additional, Temple, J., additional, Terenzi, L., additional, Tessenyi, M., additional, Testi, L., additional, Thompson, S., additional, Thrastarson, H., additional, Tingley, B. W., additional, Trifoglio, M., additional, Torres, J. Martin, additional, Tozzi, A., additional, Turrini, D., additional, Varley, R., additional, Vakili, F., additional, de Val-Borro, M., additional, Valdivieso, M. L., additional, Venot, O., additional, Villaver, E., additional, Vinatier, S., additional, Viti, S., additional, Waldmann, I., additional, Waltham, D., additional, Ward-Thompson, D., additional, Waters, R., additional, Watkins, C., additional, Watson, D., additional, Wawer, P., additional, Wawrzaszk, A., additional, White, G., additional, Widemann, T., additional, Winek, W., additional, Wi.niowski, T., additional, Yelle, R., additional, Yung, Y., additional, and Yurchenko, S. N., additional

Published
2015
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50. On the Relation Between Jovian Aurorae and the Loading/Unloading of the Magnetic Flux: Simultaneous Measurements From Juno, Hubble Space Telescope, and Hisaki

Author

A. T. Y. Lui, Barry Mauk, Fran Bagenal, Ruilong Guo, Licia C Ray, Sarah V. Badman, Kazuo Yoshioka, Shengyi Ye, Steve Levin, I. J. Rae, Aikaterini Radioti, Tomoki Kimura, William Dunn, Denis Grodent, Zhonghua Yao, Bertrand Bonfond, William S. Kurth, Benjamin Palmaerts, J. C. Gérard, George Clark, Zuyin Pu, Scott Bolton, and Jonathan D. Nichols

Subjects
Physics, 010504 meteorology & atmospheric sciences, Spacecraft, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Magnetosphere, Magnetic reconnection, F500, Astrophysics, 010502 geochemistry & geophysics, 01 natural sciences, Jovian, Magnetic flux, Magnetic field, Jupiter, Geophysics, Physics::Space Physics, General Earth and Planetary Sciences, business, 0105 earth and related environmental sciences, Radio wave
Abstract

We present simultaneous observations of aurorae at Jupiter from the Hubble Space Telescope and Hisaki, in combination with the in situ measurements of magnetic field, particles, and radio waves from the Juno Spacecraft in the outer magnetosphere, from ~ 80RJ to 60RJ during 17 to 22 March 2017. Two cycles of accumulation and release of magnetic flux, named magnetic loading/unloading, were identified during this period, which correlate well with electron energization and auroral intensifications. Magnetic reconnection events are identified during both the loading and unloading periods, indicating that reconnection and unloading are independent processes. These results show that the dynamics in the middle magnetosphere are coupled with auroral variability.

Published
2019

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