174 results on '"Bellucci, Giancarlo"'
Search Results
152. Spectral diversity and compositional implications of Montes Haemus and Serenitatis/Tranquillitatis region on the moon from imaging spectroscopy data
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Bellucci, Giancarlo, primary
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- 1998
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153. Imaging spectroscopy of the moon: data reduction-analysis techniques and compositional variability of the Mare Serenitatis-Tranquillitatis region
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Bellucci, Giancarlo, primary, Pinori, Sabrina, additional, and Formisano, Vittorio, additional
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- 1998
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154. Regional mapping of planetary surfaces with imaging spectroscopy
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Bellucci, Giancarlo, primary and Formisano, Vittorio, additional
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- 1997
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155. VIRTIS: Visible Infrared Thermal Imaging Spectrometer for the Rosetta mission
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Reininger, Francis M., primary, Coradini, Angioletta, additional, Capaccioni, Fabrizio, additional, Capria, M. T., additional, Cerroni, Priscilla, additional, De Sanctis, M. C., additional, Magni, G., additional, Drossart, Pierre, additional, Barucci, Maria A., additional, Bockelee-Morvan, D., additional, Combes, Jean-Michel, additional, Crovisier, J., additional, Encrenaz, T., additional, Reess, Jean-Michel, additional, Semery, Alain, additional, Tiphene, Didier, additional, Arnold, Gabriele, additional, Carsenty, Uri, additional, Michaelis, Harald, additional, Mottola, Stefano, additional, Neukum, Gerhard, additional, Peters, G., additional, Schade, Ulrich, additional, Taylor, Fredric W., additional, Calcutt, Simon B., additional, Vellacott, Tim, additional, Venters, P., additional, Watkins, R. E., additional, Bellucci, Giancarlo, additional, Formisano, Vittorio, additional, Angrilli, Francesco, additional, Bianchini, Gianandrea, additional, Saggin, Bortolino, additional, Bussoletti, E., additional, Colangeli, L., additional, Mennella, Vito, additional, Fonti, S., additional, Bibring, Jean-Pierre, additional, Langevin, Yves, additional, Schmitt, B., additional, Combi, M., additional, Fink, U., additional, McCord, Thomas B., additional, Ip, Wing, additional, Carlson, Robert W., additional, and Jennings, Donald E., additional
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- 1996
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156. Image sharpening by means of spectral unmixing: comparison among different techniques.
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Bellucci, Giancarlo
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- 1998
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157. VNIR: Visible/near-infrared spectrometer for the Mars 94 mission
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Bellucci, Giancarlo, primary
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- 1993
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158. Gravity waves mapped by the OMEGA/MEX instrument through O2 dayglow at 1.27 μm: Data analysis and atmospheric modeling.
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Altieri, Francesca, Spiga, Aymeric, Zasova, Ludmila, Bellucci, Giancarlo, and Bibring, Jean-Pierre
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- 2012
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159. Variations in Vertical CO/CO2Profiles in the Martian Mesosphere and Lower Thermosphere Measured by the ExoMars TGO/NOMAD: Implications of Variations in Eddy Diffusion Coefficient
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Yoshida, Nao, Nakagawa, Hiromu, Aoki, Shohei, Erwin, Justin, Vandaele, Ann Carine, Daerden, Frank, Thomas, Ian, Trompet, Loïc, Koyama, Shungo, Terada, Naoki, Neary, Lori, Murata, Isao, Villanueva, Geronimo, Liuzzi, Giuliano, Lopez‐Valverde, Miguel Angel, Brines, Adrian, Modak, Ashimananda, Kasaba, Yasumasa, Ristic, Bojan, Bellucci, Giancarlo, López‐Moreno, José Juan, and Patel, Manish
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Using the Nadir and Occultation for MArs Discovery instrument aboard Trace Gas Orbiter, we derived the CO/CO2profiles between 75 and 105 km altitude with the equivalent width technique. The derived CO/CO2profiles showed significant seasonal variations in the southern hemisphere with decreases near perihelion and increases near aphelion. The estimation of the CO/CO2profiles with a one‐dimensional photochemical model shows that an altitude‐dependent eddy diffusion coefficient better reproduces the observed profiles than a vertically uniform one. Our estimation suggests that the eddy diffusion coefficient in Ls= 240–270 is uniformly larger by a factor of ∼2 than that in Ls= 90–120 in the southern hemisphere, while they are comparable in the northern hemisphere. This fact demonstrates that the eddy diffusion coefficient is variable with season and latitude. The eddy diffusion coefficient is widely used to parameterize the efficiency of vertical diffusion in the planetary atmosphere, whose variation characterizes the transportation of trace gas species. Additionally, it could vary their vertical distributions in the middle and upper atmosphere, which might cause an impact on the species escaping to space. However, the variability of the eddy diffusion coefficient in those altitude regions have been poorly understood. In this study, we focus on the estimation of variation in the eddy diffusion coefficient by analyzing the CO and CO2measurements made by the ExoMars Trace Gas Orbiter. The observed CO/CO2ratio between altitudes of 75 and 105 km shows a significant seasonal variation in the southern hemisphere. The observed CO/CO2profiles are compared with the simulated profiles obtained with a one‐dimensional photochemical model assigning several shapes and intensity of eddy diffusion coefficient. The comparison shows that the eddy diffusion coefficient is not constant but variable depending on altitude, season, and latitude, which suggests that the efficiency of the vertical diffusion varies with season and latitude. This fact is useful to other 1D photochemical models to reproduce the seasonal and latitudinal variation of atmospheric composition. The CO/CO2profiles from 75 to 105 km measured by NOMAD aboard TGO are used to investigate variations in the eddy diffusion coefficientThe estimated CO/CO2profiles agree well with the observed profiles if altitude‐dependent eddy diffusion coefficients are consideredOur results demonstrate a substantial seasonal variation in the eddy diffusion coefficient in the southern hemisphere The CO/CO2profiles from 75 to 105 km measured by NOMAD aboard TGO are used to investigate variations in the eddy diffusion coefficient The estimated CO/CO2profiles agree well with the observed profiles if altitude‐dependent eddy diffusion coefficients are considered Our results demonstrate a substantial seasonal variation in the eddy diffusion coefficient in the southern hemisphere
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- 2022
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160. Preparing EChO space mission: laboratory simulation of planetary atmospheres
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Oschmann, Jacobus M., Clampin, Mark, Fazio, Giovanni G., MacEwen, Howard A., Claudi, Riccardo U., Erculiani, Marco S., Micela, Giuseppina, D'Alessandro, Maurizio, Galletta, Giuseppe, Giro, Enrico, Adriani, Alberto, Altieri, Francesca, Bellucci, Giancarlo, Billi, Daniela, Cecchi-Pestellini, Cesare, Ciaravella, Angela, Filacchione, Gianrico, Gilli, Gabriella, Giuranna, Marco, Grassi, Davide, Leto, Giuseppe, Pace, Emanuele, Palumbo, Maria E., Piccioni, Giuseppe, Scuderi, Salvatore, Strazzulla, Giovanni, and Turrini, Diego
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- 2014
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161. MicroMIMA FTS: design of spectrometer for Mars atmosphere investigation
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Comeron, Adolfo, Kassianov, Evgueni I., Schäfer, Klaus, Stein, Karin, Gonglewski, John D., Shatalina, Irina, Saggin, Bortolino, Scaccabarozzi, Diego, Panzeri, Roberto, and Bellucci, Giancarlo
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- 2013
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162. Determination of Venus' Interior Structure with EnVision.
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Rosenblatt, Pascal, Dumoulin, Caroline, Marty, Jean-Charles, Genova, Antonio, and Bellucci, Giancarlo
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MOMENTS of inertia ,PLANETARY interiors ,GRAVITY ,LITHOSPHERE ,VISCOSITY - Abstract
The Venusian geological features are poorly gravity-resolved, and the state of the core is not well constrained, preventing an understanding of Venus' cooling history. The EnVision candidate mission to the ESA's Cosmic Vision Programme consists of a low-altitude orbiter to investigate geological and atmospheric processes. The gravity experiment aboard this mission aims to determine Venus' geophysical parameters to fully characterize its internal structure. By analyzing the radio-tracking data that will be acquired through daily operations over six Venusian days (four Earth's years), we will derive a highly accurate gravity field (spatial resolution better than ~170 km), allowing detection of lateral variations of the lithosphere and crust properties beneath most of the geological features. The expected 0.3% error on the Love number k
2 , 0.1° error on the tidal phase lag and 1.4% error on the moment of inertia are fundamental to constrain the core size and state as well as the mantle viscosity. [ABSTRACT FROM AUTHOR]- Published
- 2021
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163. First Detection and Thermal Characterization of Terminator CO2Ice Clouds With ExoMars/NOMAD
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Liuzzi, Giuliano, Villanueva, Geronimo L., Trompet, Loïc, Crismani, Matteo M. J., Piccialli, Arianna, Aoki, Shohei, Lopez‐Valverde, Miguel Angel, Stolzenbach, Aurélien, Daerden, Frank, Neary, Lori, Smith, Michael D., Patel, Manish R., Lewis, Stephen R., Clancy, R. Todd, Thomas, Ian R., Ristic, Bojan, Bellucci, Giancarlo, Lopez‐Moreno, Jose‐Juan, and Vandaele, Ann Carine
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We present observations of terminator CO2ice clouds events in three groups: Equatorial dawn, Equatorial dusk (both between 20°S and 20°N) and Southern midlatitudes at dawn (45°S and 55°S east of Hellas Basin) with ESA ExoMars Trace Gas Orbiter's Nadir and Occultation for MArs Discovery instrument. CO2ice abundance is retrieved simultaneously with water ice, dust, and particle sizes, and rotational temperature and CO2column profiles in 16 of 26 cases. Small particles (<0.5 μm) prevail at dusk, while water ice likely provides most source nuclei at dawn. Clouds east of Hellas are found to be dominantly nucleated on surface‐lifted dust. CO2ice is sometimes detected in unsaturated air together with dust nuclei at dawn, suggesting ongoing sublimation. Depending on latitude and local time, the interplay between particle precipitation and the lifetime of temperature minima (i.e., cold pockets) determines CO2ice properties. The upper atmosphere of Mars is characterized by the seasonal presence of CO2ice clouds. Their properties have been long studied, as well as their formation mechanisms in relation to the thermal structure of the atmosphere and its variability. In this study, we present the first observations of these clouds at the terminator (dawn and dusk) by the NOMAD spectrometer onboard the Exomars Trace Gas Orbiter. CO2ice is detected simultaneously with dust, water ice and the temperature profile. Our results agree with previous findings in terms of how clouds are spatially distributed and their temporal occurrence. However, we also explore the sources of condensation nuclei for CO2ice particles, showing that water ice is a possible source at dawn near the Equator. We also identify surface‐lifted dust below the CO2ice clouds observed east of Hellas Basin, suggesting that, at that location, dust could provide nuclei for CO2ice. CO2ice is also sometimes detected at temperatures higher than the CO2freezing point, suggesting ongoing sublimation. In this work we explore for the first time the composition of CO2ice clouds, which is critical to advance our understanding of how CO2ice clouds form in the mesosphere at Mars. Twenty Six mesospheric CO2ice clouds were detected with NOMAD SO in Mars Year 35, simultaneously with water ice, dust, and CO2saturation ratiosEquatorial CO2clouds are observed at 50–80 km altitude at dusk, and 40–60 km at dawn, when water ice likely provides condensation nucleiSix CO2ice clouds are found east of Hellas basin; their formation is likely sourced by surface‐lifted dust at 40–65 km Twenty Six mesospheric CO2ice clouds were detected with NOMAD SO in Mars Year 35, simultaneously with water ice, dust, and CO2saturation ratios Equatorial CO2clouds are observed at 50–80 km altitude at dusk, and 40–60 km at dawn, when water ice likely provides condensation nuclei Six CO2ice clouds are found east of Hellas basin; their formation is likely sourced by surface‐lifted dust at 40–65 km
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- 2021
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164. Self-Secondaries Formed by Cold Spot Craters on the Moon.
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Chang, Yiren, Xiao, Zhiyong, Liu, Yang, Cui, Jun, and Bellucci, Giancarlo
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LUNAR craters ,IMPACT craters ,MECHANICAL shock ,LUNAR soil ,MOON - Abstract
Self-secondaries are a population of background secondaries, and they have been observed on top of impact melt and ballistically emplaced ejecta deposits on various planetary bodies. Self-secondaries are formed by impacts of sub-vertically launched ejecta, but the launch mechanism is not confirmed. The potential threat of self-secondaries to the theoretical and applicable reliability of crater chronology has been noted, but not constrained. Hitherto discovered self-secondaries were located around complex impact craters, but their potential existence around simple craters has not been discovered. Here we report the first discovery of self-secondaries around lunar cold spot craters, which are an extremely young population of simple craters formed within the past ~1 million years on the Moon. Self-secondaries are widespread on layers of cascading flow-like ejecta deposits around cold spot craters. The spatial density of self-secondaries dwarfs that of potential primary craters. The spatial distribution of self-secondaries is highly heterogeneous across the ejecta deposits. With respect to the impactor trajectory that formed cold spot craters, self-secondaries formed at the downrange of the ejecta deposits have the largest spatial density, while those at the uprange have the smallest density. This density pattern holds for all cold spot craters that were formed by non-vertical impacts, but self-secondaries do not exhibit other systematic density variations at different radial distances or at other azimuths with respect to the impactor trajectory. Among known mechanics of ejecting materials to the exterior of impact craters, impact spallation is the most likely scenario to account for the required large ejection velocities and angles to form self-secondaries. The production population of self-secondaries is estimated based on the highly diverse crater size-frequency distributions across the ejecta deposits of cold spot craters. For a better understanding of the impact history on the Moon, a systematic investigation for the effect of self-secondaries on lunar crater chronology is required. [ABSTRACT FROM AUTHOR]
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- 2021
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165. The Temporal Variation of Optical Depth in the Candidate Landing Area of China's Mars Mission (Tianwen-1).
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Tang, Zhencheng, Liu, Jianjun, Wang, Xing, Ren, Xin, Yan, Wei, Chen, Wangli, and Bellucci, Giancarlo
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MARTIAN atmosphere ,HIGH resolution imaging ,DUST ,MARS (Planet) ,OPTICAL remote sensing ,REMOTE sensing ,MARTIAN exploration - Abstract
The atmospheric dust is an important factor in the evolution of the Martian climate and has a major impact on the scientific exploration of the Martian lander or rover and its payload. This paper used remote sensing images to calculate atmospheric optical depth that characterizes the spatial distribution of the atmospheric dust of Mars. The optical depth calculated by the images of the High Resolution Imaging Science Experiment (HiRISE) in the inspection area of the Spirit rover had a similar temporal variation to the optical depth directly measured by the Spirit rover from the sunlight decay. We also used the HiRISE images to acquire the seasonal variation of optical depths in the candidate landing area of China's Mars Mission (Tianwen-1). The results have shown that the seasonal pattern of the optical depth in the candidate landing area is consistent with the dust storm sequences in this area. After Tianwen-1 enters the orbit around Mars, the images collected by the Moderate Resolution Imaging Camera (MoRIC), and the High Resolution Imaging Camera (HiRIC) can be used to study the atmospheric optical depth in the candidate landing area, providing reference for the safe landing and operation of the lander and rover. [ABSTRACT FROM AUTHOR]
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- 2021
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166. Impact of the 2018 Mars global dust storm on water vapour as observed by NOMAD on ExoMars Trace Gas Orbiter.
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Vandaele, Ann Carine, Daerden, Frank, Thomas, Ian R., Aoki, Shohei, Depiesse, Cedric, Erwin, Justin, Neary, Lori, Piccialli, Arianna, Ristic, Bojan, Robert, Severine, Trompet, Loïc, Viscardy, Sebastien, Willame, Yannick, Wilquet, Valerie, Altieri, Francesca, Smith, Michael, Villanueva, Geronimo, Lopez-Moreno, Jose-Juan, Bellucci, Giancarlo, and Patel, Manish R.
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- 2019
167. Ozone vertical profiles from NOMAD-UVIS: a preliminary analysis.
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Piccialli, Arianna, Vandaele, Ann Carine, Willame, Yannick, Depiesse, Cedric, Trompet, Loïc, Neary, Lori, Viscardy, Sebastien, Daerden, Frank, Thomas, Ian R., Ristic, Bojan, Mason, Jon P., Patel, Manish R., Bellucci, Giancarlo, and Lopez-Moreno, Jose-Juan
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- 2019
168. A chemical survey of exoplanets with ARIEL
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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
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13. Climate action ,530 Physics ,520 Astronomy ,Astrophysics::Earth and Planetary Astrophysics ,500 Science ,7. Clean energy - Abstract
Thousands of exoplanets have now been discovered with a huge range of masses, sizes and orbits: from rocky Earth-like planets to large gas giants grazing the surface of their host star. However, the essential nature of these exoplanets remains largely mysterious: there is no known, discernible pattern linking the presence, size, or orbital parameters of a planet to the nature of its parent star. We have little idea whether the chemistry of a planet is linked to its formation environment, or whether the type of host star drives the physics and chemistry of the planet’s birth, and evolution. ARIEL was conceived to observe a large number (~1000) of transiting planets for statistical understanding, including gas giants, Neptunes, super-Earths and Earth-size planets around a range of host star types using transit spectroscopy in the 1.25–7.8 μm spectral range and multiple narrow-band photometry in the optical. ARIEL will focus on warm and hot planets to take advantage of their well-mixed atmospheres which should show minimal condensation and sequestration of high-Z materials compared to their colder Solar System siblings. Said warm and hot atmospheres are expected to be more representative of the planetary bulk composition. Observations of these warm/hot exoplanets, and in particular of their elemental composition (especially C, O, N, S, Si), will allow the understanding of the early stages of planetary and atmospheric formation during the nebular phase and the following few million years. ARIEL will thus provide a representative picture of the chemical nature of the exoplanets and relate this directly to the type and chemical environment of the host star. ARIEL is designed as a dedicated survey mission for combined-light spectroscopy, capable of observing a large and well-defined planet sample within its 4-year mission lifetime. Transit, eclipse and phase-curve spectroscopy methods, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allow us to measure atmospheric signals from the planet at levels of 10–100 part per million (ppm) relative to the star and, given the bright nature of targets, also allows more sophisticated techniques, such as eclipse mapping, to give a deeper insight into the nature of the atmosphere. These types of observations require a stable payload and satellite platform with broad, instantaneous wavelength coverage to detect many molecular species, probe the thermal structure, identify clouds and monitor the stellar activity. The wavelength range proposed covers all the expected major atmospheric gases from e.g. H₂O, CO₂, CH₄ NH₃, HCN, H₂S through to the more exotic metallic compounds, such as TiO, VO, and condensed species. Simulations of ARIEL performance in conducting exoplanet surveys have been performed – using conservative estimates of mission performance and a full model of all significant noise sources in the measurement – using a list of potential ARIEL targets that incorporates the latest available exoplanet statistics. The conclusion at the end of the Phase A study, is that ARIEL – in line with the stated mission objectives – will be able to observe about 1000 exoplanets depending on the details of the adopted survey strategy, thus confirming the feasibility of the main science objectives.
169. Martian dust storm impact on atmospheric H₂O and D/H observed by ExoMars Trace Gas Orbiter
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Vandaele, Ann Carine, Korablev, Oleg, Daerden, Frank, Aoki, Shohei, Thomas, Ian R., Altieri, Francesca, López-Valverde, Miguel, Villanueva, Geronimo, Liuzzi, Giuliano, Smith, Michael D., Erwin, Justin T., Trompet, Loïc, Fedorova, Anna A., Montmessin, Franck, Trokhimovskiy, Alexander, Belyaev, Denis A., Ignatiev, Nikolay I., Luginin, Mikhail, Olsen, Kevin S., Baggio, Lucio, Alday, Juan, Bertaux, Jean-Loup, Betsis, Daria, Bolsée, David, Clancy, R. Todd, Cloutis, Edward, Depiesse, Cédric, Funke, Bernd, Garcia-Comas, Maia, Gérard, Jean-Claude, Giuranna, Marco, Gonzalez-Galindo, Francisco, Grigoriev, Alexey V., Ivanov, Yuriy S., Kaminski, Jacek, Karatekin, Ozgur, Lefèvre, Franck, Lewis, Stephen, López-Puertas, Manuel, Mahieux, Arnaud, Maslov, Igor, Mason, Jon, Mumma, Michael J., Neary, Lori, Neefs, Eddy, Patrakeev, Andrey, Patsaev, Dmitry, Ristic, Bojan, Robert, Séverine, Schmidt, Frédéric, Shakun, Alexey, Teanby, Nicholas A., Viscardy, Sébastien, Willame, Yannick, Whiteway, James, Wilquet, Valérie, Wolff, Michael J., Bellucci, Giancarlo, Patel, Manish R., López-Moreno, Jose-Juan, Forget, François, Wilson, Colin F., Svedhem, Håkan, Vago, Jorge L., and Rodionov, Daniel
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13. Climate action ,520 Astronomy ,620 Engineering - Abstract
Global dust storms on Mars are rare but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere, primarily owing to solar heating of the dust. In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars. Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes, as well as a decrease in the water column at low latitudes. Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H₂O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H₂O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals. The observed changes in H₂O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.
170. NOMAD spectrometer on the ExoMars trace gas orbiter mission: part 2—design, manufacturing, and testing of the ultraviolet and visible channel
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Patel, Manish R., Antoine, Philippe, Mason, Jonathon, Leese, Mark, Hathi, Brijen, Stevens, Adam H., Dawson, Daniel, Gow, Jason, Ringrose, Timothy, Holmes, James, Lewis, Stephen R., Beghuin, Didier, van Donink, Philip, Ligot, Renaud, Dewandel, Jean-Luc, Hu, Daohua, Bates, Doug, Cole, Richard, Drummond, Rachel, Thomas, Ian R., Depiesse, Cédric, Neefs, Eddy, Equeter, Eddy, Ristic, Bojan, Berkenbosch, Sophie, Bolsée, David, Willame, Yannick, Vandaele, Ann Carine, Lesschaeve, Stefan, De Vos, Lieve, Van Vooren, Nico, Thibert, Tanguy, Mazy, Emmanuel, Rodriguez-Gomez, Julio, Morales, Rafael, Candini, Gian Paolo, Pastor-Morales, M. Carmen, Sanz, Rosario, Aparicio del Moral, Beatriz, Jeronimo-Zafra, José-Maria, Gómez-López, Juan Manuel, Alonso-Rodrigo, Gustavo, Pérez-Grande, Isabel, Cubas, Javier, Gomez-Sanjuan, Alejandro M., Navarro-Medina, Fermín, BenMoussa, Ali, Giordanengo, Boris, Gissot, Samuel, Bellucci, Giancarlo, and Lopez-Moreno, Jose Juan
- Abstract
NOMAD is a spectrometer suite on board the ESA/Roscosmos ExoMars Trace Gas Orbiter, which launched in March 2016. NOMAD consists of two infrared channels and one ultraviolet and visible channel, allowing the instrument to perform observations quasi-constantly, by taking nadir measurements at the day- and night-side, and during solar occultations. Here, in part 2 of a linked study, we describe the design, manufacturing, and testing of the ultraviolet and visible spectrometer channel called UVIS. We focus upon the optical design and working principle where two telescopes are coupled to a single grating spectrometer using a selector mechanism.
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171. Water heavily fractionated as it ascends on Mars as revealed by ExoMars/NOMAD.
- Author
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Villanueva GL, Liuzzi G, Crismani MMJ, Aoki S, Vandaele AC, Daerden F, Smith MD, Mumma MJ, Knutsen EW, Neary L, Viscardy S, Thomas IR, Lopez-Valverde MA, Ristic B, Patel MR, Holmes JA, Bellucci G, and Lopez-Moreno JJ
- Abstract
Isotopic ratios and, in particular, the water D/H ratio are powerful tracers of the evolution and transport of water on Mars. From measurements performed with ExoMars/NOMAD, we observe marked and rapid variability of the D/H along altitude on Mars and across the whole planet. The observations (from April 2018 to April 2019) sample a broad range of events on Mars, including a global dust storm, the evolution of water released from the southern polar cap during southern summer, the equinox phases, and a short but intense regional dust storm. In three instances, we observe water at very high altitudes (>80 km), the prime region where water is photodissociated and starts its escape to space. Rayleigh distillation appears the be the driving force affecting the D/H in many cases, yet in some instances, the exchange of water reservoirs with distinctive D/H could be responsible., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)
- Published
- 2021
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172. Martian dust storm impact on atmospheric H 2 O and D/H observed by ExoMars Trace Gas Orbiter.
- Author
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Vandaele AC, Korablev O, Daerden F, Aoki S, Thomas IR, Altieri F, López-Valverde M, Villanueva G, Liuzzi G, Smith MD, Erwin JT, Trompet L, Fedorova AA, Montmessin F, Trokhimovskiy A, Belyaev DA, Ignatiev NI, Luginin M, Olsen KS, Baggio L, Alday J, Bertaux JL, Betsis D, Bolsée D, Clancy RT, Cloutis E, Depiesse C, Funke B, Garcia-Comas M, Gérard JC, Giuranna M, Gonzalez-Galindo F, Grigoriev AV, Ivanov YS, Kaminski J, Karatekin O, Lefèvre F, Lewis S, López-Puertas M, Mahieux A, Maslov I, Mason J, Mumma MJ, Neary L, Neefs E, Patrakeev A, Patsaev D, Ristic B, Robert S, Schmidt F, Shakun A, Teanby NA, Viscardy S, Willame Y, Whiteway J, Wilquet V, Wolff MJ, Bellucci G, Patel MR, López-Moreno JJ, Forget F, Wilson CF, Svedhem H, Vago JL, and Rodionov D
- Abstract
Global dust storms on Mars are rare
1,2 but can affect the Martian atmosphere for several months. They can cause changes in atmospheric dynamics and inflation of the atmosphere3 , primarily owing to solar heating of the dust3 . In turn, changes in atmospheric dynamics can affect the distribution of atmospheric water vapour, with potential implications for the atmospheric photochemistry and climate on Mars4 . Recent observations of the water vapour abundance in the Martian atmosphere during dust storm conditions revealed a high-altitude increase in atmospheric water vapour that was more pronounced at high northern latitudes5,6 , as well as a decrease in the water column at low latitudes7,8 . Here we present concurrent, high-resolution measurements of dust, water and semiheavy water (HDO) at the onset of a global dust storm, obtained by the NOMAD and ACS instruments onboard the ExoMars Trace Gas Orbiter. We report the vertical distribution of the HDO/H2 O ratio (D/H) from the planetary boundary layer up to an altitude of 80 kilometres. Our findings suggest that before the onset of the dust storm, HDO abundances were reduced to levels below detectability at altitudes above 40 kilometres. This decrease in HDO coincided with the presence of water-ice clouds. During the storm, an increase in the abundance of H2 O and HDO was observed at altitudes between 40 and 80 kilometres. We propose that these increased abundances may be the result of warmer temperatures during the dust storm causing stronger atmospheric circulation and preventing ice cloud formation, which may confine water vapour to lower altitudes through gravitational fall and subsequent sublimation of ice crystals3 . The observed changes in H2 O and HDO abundance occurred within a few days during the development of the dust storm, suggesting a fast impact of dust storms on the Martian atmosphere.- Published
- 2019
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173. No detection of methane on Mars from early ExoMars Trace Gas Orbiter observations.
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Korablev O, Vandaele AC, Montmessin F, Fedorova AA, Trokhimovskiy A, Forget F, Lefèvre F, Daerden F, Thomas IR, Trompet L, Erwin JT, Aoki S, Robert S, Neary L, Viscardy S, Grigoriev AV, Ignatiev NI, Shakun A, Patrakeev A, Belyaev DA, Bertaux JL, Olsen KS, Baggio L, Alday J, Ivanov YS, Ristic B, Mason J, Willame Y, Depiesse C, Hetey L, Berkenbosch S, Clairquin R, Queirolo C, Beeckman B, Neefs E, Patel MR, Bellucci G, López-Moreno JJ, Wilson CF, Etiope G, Zelenyi L, Svedhem H, and Vago JL
- Abstract
The detection of methane on Mars has been interpreted as indicating that geochemical or biotic activities could persist on Mars today
1 . A number of different measurements of methane show evidence of transient, locally elevated methane concentrations and seasonal variations in background methane concentrations2-5 . These measurements, however, are difficult to reconcile with our current understanding of the chemistry and physics of the Martian atmosphere6,7 , which-given methane's lifetime of several centuries-predicts an even, well mixed distribution of methane1,6,8 . Here we report highly sensitive measurements of the atmosphere of Mars in an attempt to detect methane, using the ACS and NOMAD instruments onboard the ESA-Roscosmos ExoMars Trace Gas Orbiter from April to August 2018. We did not detect any methane over a range of latitudes in both hemispheres, obtaining an upper limit for methane of about 0.05 parts per billion by volume, which is 10 to 100 times lower than previously reported positive detections2,4 . We suggest that reconciliation between the present findings and the background methane concentrations found in the Gale crater4 would require an unknown process that can rapidly remove or sequester methane from the lower atmosphere before it spreads globally.- Published
- 2019
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174. Optical and radiometric models of the NOMAD instrument part I: the UVIS channel.
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Vandaele AC, Willame Y, Depiesse C, Thomas IR, Robert S, Bolsée D, Patel MR, Mason JP, Leese M, Lesschaeve S, Antoine P, Daerden F, Delanoye S, Drummond R, Neefs E, Ristic B, Lopez-Moreno JJ, Bellucci G, and Team N
- Abstract
The NOMAD instrument has been designed to best fulfil the science objectives of the ExoMars Trace Gas Orbiter mission that will be launched in 2016. The instrument is a combination of three channels that cover the UV, visible and IR spectral ranges and can perform solar occultation, nadir and limb observations. In this series of two papers, we present the optical models representing the three channels of the instrument and use them to determine signal to noise levels for different observation modes and Martian conditions. In this first part, we focus on the UVIS channel, which will sound the Martian atmosphere using nadir and solar occultation viewing modes, covering the 200-650nm spectral range. High SNR levels (>1000) can easily be reached for wavelengths higher than 300nm both in solar occultation and nadir modes when considering binning. Below 300nm SNR are lower primarily because of the lower signal and the impact of atmospheric absorption.
- Published
- 2015
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