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174 results on '"Widemann, T."'

1. A sub-Neptune planet around TOI-1695 discovered and characterized with SPIRou and TESS

Author: Kiefer, F., Hébrard, G., Martioli, E., Artigau, E., Doyon, R., Donati, J. -F., Cadieux, C., Carmona, A., Ciardi, D. R., Cristofari, P. I., de Almeida, L., Figueira, P., Gaidos, E., Gonzales, E., Lecavelier, A., Stassun, K. G., Arnold, L., Benneke, B., Boisse, I., Bonfils, X., Cook, N. J., Cortés-Zuleta, P., Delfosse, X., Nascimento, J. Dias do, Fausnaugh, M., Fong, W., Fouqué, P., Forveille, T., da Silva, J. Gomes, Hesse, K., Kóspál, Á., Lewis, H., Liu, C. -F., Martins, J. H. C., Paegert, M., Seager, S., Shang, H., Twicken, J. D., Vandal, T., Vinatier, S., Widemann, T., and Winn, J. N.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: TOI-1695 is a V-mag=13 M-dwarf star from the northern hemisphere at 45$\,$pc from the Sun, around which a 3.134-day periodic transit signal from a super-Earth candidate was identified in TESS photometry. With a transit depth of 1.3$\,$mmag, the radius of candidate TOI-1695.01 was estimated by the TESS pipeline to be 1.82$\,$R$_\oplus$ with an equilibrium temperature of $\sim 620\,$K. We successfully detect a reflex motion of the star and establish it is due to a planetary companion at an orbital period consistent with the photometric transit period thanks to a year-long radial-velocity monitoring of TOI-1695 by the SPIRou infrared spectropolarimeter. We use and compare different methods to reduce and analyse those data. We report a 5.5-$\sigma$ detection of the planetary signal, giving a mass of $5.5 \pm 1.0\,$M$_\oplus$ and a radius of $2.03 \pm 0.18\,$R$_\oplus$. We derive a mean equilibrium planet temperature of $590 \pm 90\,$K. The mean density of this small planet of $3.6 \pm 1.1\,$g$\,$cm$^{-3}$ is similar (1.7-$\sigma$ lower) than that of the Earth. It leads to a non-negligible fraction of volatiles in its atmosphere with $f_{H,He}=0.28^{+0.46}_{-0.23}$% or $f_\text{water}=23 \pm 12$%. TOI-1695$\,$b is a new sub-Neptune planet at the border of the M-dwarf radius valley that can help test formation scenarios for super-Earth/sub-Neptune-like planets., Comment: 15 pages (+9 appendix pages), 19 figures, 8 tables, accepted for publication in A&A
Published: 2022
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2. Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

Author: Oliveira, J. Marques, Sicardy, B., Gomes-Júnior, A. R., Ortiz, J. L., Strobel, D. F., Bertrand, T., Forget, F., Lellouch, E., Desmars, J., Bérard, D., Doressoundiram, A., Lecacheux, J., Leiva, R., Meza, E., Roques, F., Souami, D., Widemann, T., Santos-Sanz, P., Morales, N., Duffard, R., Fernández-Valenzuela, E., Castro-Tirado, A. J., Braga-Ribas, F., Morgado, B. E., Assafin, M., Camargo, J. I. B., Vieira-Martins, R., Benedetti-Rossi, G., Santos-Filho, S., Banda-Huarca, M. V., Quispe-Huaynasi, F., Pereira, C. L., Rommel, F. L., Margoti, G., Dias-Oliveira, A., Colas, F., Berthier, J., Renner, S., Hueso, R., Pérez-Hoyos, S., Sánchez-Lavega, A., Rojas, J. F., Beisker, W., Kretlow, M., Herald, D., Gault, D., Bath, K. -L., Bode, H. -J., Bredner, E., Guhl, K., Haymes, T. V., Hummel, E., Kattentidt, B., Klös, O., Pratt, A., Thome, B., Avdellidou, C., Gazeas, K., Karampotsiou, E., Tzouganatos, L., Kardasis, E., Christou, A. A., Xilouris, E. M., Alikakos, I., Gourzelas, A., Liakos, A., Charmandaris, V., Jelínek, M., Štrobl, J., Eberle, A., Rapp, K., Gährken, B., Klemt, B., Kowollik, S., Bitzer, R., Miller, M., Herzogenrath, G., Frangenberg, D., Brandis, L., Pütz, I., Perdelwitz, V., Piehler, G. M., Riepe, P., von Poschinger, K., Baruffetti, P., Cenadelli, D., Christille, J. -M., Ciabattari, F., Di Luca, R., Alboresi, D., Leto, G., Sanchez, R. Zanmar, Bruno, P., Occhipinti, G., Morrone, L., Cupolino, L., Noschese, A., Vecchione, A., Scalia, C., Savio, R. Lo, Giardina, G., Kamoun, S., Barbosa, R., Behrend, R., Spano, M., Bouchet, E., Cottier, M., Falco, L., Gallego, S., Tortorelli, L., Sposetti, S., Sussenbach, J., Abbeel, F. Van Den, André, P., Llibre, M., Pailler, F., Ardissone, J., Boutet, M., Sanchez, J., Bretton, M., Cailleau, A., Pic, V., Granier, L., Chauvet, R., Conjat, M., Dauvergne, J. L., Dechambre, O., Delay, P., Delcroix, M., Rousselot, L., Ferreira, J., Machado, P., Tanga, P., Rivet, J. -P., Frappa, E., Irzyk, M., Jabet, F., Kaschinski, M., Klotz, A., Rieugnie, Y., Klotz, A. N., Labrevoir, O., Lavandier, D., Walliang, D., Leroy, A., Bouley, S., Lisciandra, S., Coliac, J. -F., Metz, F., Erpelding, D., Nougayrède, P., Midavaine, T., Miniou, M., Moindrot, S., Morel, P., Reginato, B., Reginato, E., Rudelle, J., Tregon, B., Tanguy, R., David, J., Thuillot, W., Hestroffer, D., Vaudescal, G., Aissa, D. Baba, Grigahcene, Z., Briggs, D., Broadbent, S., Denyer, P., Haigh, N. J., Quinn, N., Thurston, G., Fossey, S. J., Arena, C., Jennings, M., Talbot, J., Alonso, S., Reche, A. Román, Casanova, V., Briggs, E., Iglesias-Marzoa, R., Ibáñez, J. Abril, Martín, M. C. Díaz, González, H., García, J. L. Maestre, Marchant, J., Ordonez-Etxeberria, I., Martorell, P., Salamero, J., Organero, F., Ana, L., Fonseca, F., Peris, V., Brevia, O., Selva, A., Perello, C., Cabedo, V., Gonçalves, R., Ferreira, M., Dias, F. Marques, Daassou, A., Barkaoui, K., Benkhaldoun, Z., Guennoun, M., Chouqar, J., Jehin, E., Rinner, C., Lloyd, J., Moutamid, M. El, Lamarche, C., Pollock, J. T., Caton, D. B., Kouprianov, V., Timerson, B. W., Blanchard, G., Payet, B., Peyrot, A., Teng-Chuen-Yu, J. -P., Françoise, J., Mondon, B., Payet, T., Boissel, C., Castets, M., Hubbard, W. B., Hill, R., Reitsema, H. J., Mousis, O., Ball, L., Neilsen, G., Hutcheon, S., Lay, K., Anderson, P., Moy, M., Jonsen, M., Pink, I., Walters, R., and Downs, B.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range $\sim$8 km to $\sim$190 km, corresponding to pressure levels from 9 {\mu}bar down to a few nanobars. Results. (i) A pressure of 1.18$\pm$0.03 {\mu}bar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 {\mu}bar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude., Comment: 52 pages, 26 figures in the main paper, 2 figures in appendix B, 9 figures in appendix C, 1 long table over 5 pages
Published: 2022
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3. A stringent upper limit of the PH$_3$ abundance at the cloud top of Venus

Author: Encrenaz, T., Greathouse, T. K., Marcq, E., Widemann, T., Bézard, B., Fouchet, T., Giles, R., Sagawa, H., Greaves, J., and Sousa-Silva, C.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Following the announcement of the detection of phosphine (PH$_3$) in the cloud deck of Venus at millimeter wavelengths, we have searched for other possible signatures of this molecule in the infrared range. Since 2012, we have been observing Venus in the thermal infrared at various wavelengths to monitor the behavior of SO$_2$ and H$_2$O at the cloud top. We have identified a spectral interval recorded in March 2015 around 950 cm$^{-1}$ where a PH$_3$ transition is present. From the absence of any feature at this frequency, we derive, on the disk-integrated spectrum, a 3-$\sigma$ upper limit of 5 ppbv for the PH$_3$ mixing ratio, assumed to be constant throughout the atmosphere. This limit is 4 times lower than the disk-integrated mixing ratio derived at millimeter wavelengths. Our result brings a strong constraint on the maximum PH$_3$ abundance at the cloud top and in the lower mesosphere of Venus., Comment: Astronomy & Astrophysics, in press
Published: 2020
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4. Pluto's lower atmosphere and pressure evolution from ground-based stellar occultations, 1988-2016

Author: Meza, E., Sicardy, B., Assafin, M., Ortiz, J. L., Bertrand, T., Lellouch, E., Desmars, J., Forget, F., Bérard, D., Doressoundiram, A., Lecacheux, J., Oliveira, J. Marques, Roques, F., Widemann, T., Colas, F., Vachier, F., Renner, S., Leiva, R., Braga-Ribas, F., Benedetti-Rossi, G., Camargo, J. I. B., Dias-Oliveira, A., Morgado, B., Gomes-Júnior, A. R., Vieira-Martins, R., Behrend, R., Tirado, A. Castro, Duffard, R., Morales, N., Santos-Sanz, P., Jelínek, M., Cunniffe, R., Querel, R., Harnisch, M., Jansen, R., Pennell, A., Todd, S., Ivanov, V. D., Opitom, C., Gillon, M., Jehin, E., Manfroid, J., Pollock, J., Reichart, D. E., Haislip, J. B., Ivarsen, K. M., LaCluyze, A. P., Maury, A., Gil-Hutton, R., Dhillon, V., Littlefair, S., Marsh, T., Veillet, C., Bath, K. -L., Beisker, W., Bode, H. -J., Kretlow, M., Herald, D., Gault, D., Kerr, S., Pavlov, H., Faragó, O., Klös, O., Frappa, E., Lavayssière, M., Cole, A. A., Giles, A. B., Greenhill, J. G., Hill, K. M., Buie, M. W., Olkin, C. B., Young, E. F., Young, L. A., Wasserman, L. H., Devogèle, M., French, R. G., Bianco, F. B., Marchis, F., Brosch, N., Kaspi, S., Polishook, D., Manulis, I., Larbi, M. Ait Moulay, Benkhaldoun, Z., Daassou, A., Azhari, Y. El, Moulane, Y., Broughton, J., Milner, J., Dobosz, T., Bolt, G., Lade, B., Gilmore, A., Kilmartin, P., Allen, W. H., Graham, P. B., Loader, B., McKay, G., Talbot, J., Parker, S., Abe, L., Bendjoya, Ph., Rivet, J. -P., Vernet, D., Di Fabrizio, L., Lorenzi, V., Magazzù, A., Molinari, E., Gazeas, K., Tzouganatos, L., Carbognani, A., Bonnoli, G., Marchini, A., Leto, G., Sanchez, R. Zanmar, Mancini, L., Kattentidt, B., Dohrmann, M., Guhl, K., Rothe, W., Walzel, K., Wortmann, G., Eberle, A., Hampf, D., Ohlert, J., Krannich, G., Murawsky, G., Gährken, B., Gloistein, D., Alonso, S., Román, A., Communal, J. -E., Jabet, F., de Visscher, S., Sérot, J., Janik, T., Moravec, Z., Machado, P., Selva, A., Perelló, C., Rovira, J., Conti, M., Papini, R., Salvaggio, F., Noschese, A., Tsamis, V., Tigani, K., Barroy, P., Irzyk, M., Neel, D., Godard, J. P., Lanoiselée, D., Sogorb, P., Vérilhac, D., Bretton, M., Signoret, F., Ciabattari, F., Naves, R., Boutet, M., De Queiroz, J., Lindner, P., Lindner, K., Enskonatus, P., Dangl, G., Tordai, T., Eichler, H., Hattenbach, J., Peterson, C., Molnar, L. A., and Howell, R. R.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. Pluto's tenuous nitrogen (N2) atmosphere undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has been recently (July 2015) observed by the New Horizons spacecraft. Goals are (i) construct a well calibrated record of the seasonal evolution of surface pressure on Pluto and (ii) constrain the structure of the lower atmosphere using a central flash observed in 2015. Method: eleven stellar occultations by Pluto observed between 2002 and 2016 are used to retrieve atmospheric profiles (density, pressure, temperature) between $\sim$5 km and $\sim$380 km altitude levels (i.e. pressures from about 10 microbar to 10 nanobar). Results: (i) Pressure has suffered a monotonic increase from 1988 to 2016, that is compared to a seasonal volatile transport model, from which tight constraints on a combination of albedo and emissivity of N2 ice are derived; (ii) A central flash observed on 2015 June 29 is consistent with New Horizons REX profiles, provided that (a) large diurnal temperature variations (not expected by current models) occur over Sputnik Planitia and/or (b) hazes with tangential optical depth of about 0.3 are present at 4-7 km altitude levels and/or (c) the nominal REX density values are overestimated by an implausibly large factor of about 20% and/or (d) higher terrains block part of the flash in the Charon facing hemisphere., Comment: 21 pages, 11 figures
Published: 2019
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5. Study of the plutino object (208996) 2003 AZ84 from stellar occultations: size, shape and topographic features

Author: Dias-Oliveira, A., Sicardy, B., Ortiz, J. L., Braga-Ribas, F., Leiva, R., Vieira-Martins, R., Benedetti-Rossi, G., Camargo, J. I. B., Assafin, M., Gomes-Junior, A. R., Baug, T., Chandrasekhar, T., Desmars, J., Duffard, R., Santos-Sanz, P., Ergang, Z., Ganesh, S., Ikari, Y., Irawati, P., Jain, J., Liying, Z., Richichi, A., Shengbang, Q., Behrend, R., Benkhaldoun, Z., Brosch, N., Daassou, A., Frappa, E., Gal-Yam, A., Garcia-Lozano, R., Gillon, M., Jehin, E., Kaspi, S., Klotz, A., Lecacheux, J., Mahasena, P., Manfroid, J., Manulis, I., Maury, A., Mohan, V., Morales, N., Ofek, E., Rinner, C., Sharma, A., Sposetti, S., Tanga, P., Thirouin, A., Vachier, F., Widemann, T., Asai, A., Watanabe, Hayato, Watanabe, Hiroyuki, Owada, M., Yamamura, H., Hayamizu, T., Bradshaw, J., Kerr, S., Tomioka, H., Andersson, S., Dangl, G., Haymes, T., Naves, R., and Wortmann, G
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We present results derived from four stellar occultations by the plutino object (208996) 2003~AZ$_{84}$, detected at January 8, 2011 (single-chord event), February 3, 2012 (multi-chord), December 2, 2013 (single-chord) and November 15, 2014 (multi-chord). Our observations rule out an oblate spheroid solution for 2003~AZ$_{84}$'s shape. Instead, assuming hydrostatic equilibrium, we find that a Jacobi triaxial solution with semi axes $(470 \pm 20) \times (383 \pm 10) \times (245 \pm 8)$~km % axis ratios $b/a= 0.82 \pm 0.05$ and $c/a= 0.52 \pm 0.02$, can better account for all our occultation observations. Combining these dimensions with the rotation period of the body (6.75~h) and the amplitude of its rotation light curve, we derive a density $\rho=0.87 \pm 0.01$~g~cm$^{-3}$ a geometric albedo $p_V= 0.097 \pm 0.009$. A grazing chord observed during the 2014 occultation reveals a topographic feature along 2003~AZ$_{84}$'s limb, that can be interpreted as an abrupt chasm of width $\sim 23$~km and depth $> 8$~km or a smooth depression of width $\sim 80$~km and depth $\sim 13$~km (or an intermediate feature between those two extremes).
Published: 2017
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6. Stringent upper limits of minor species at the cloud top of Venus: PH3, HCN, and NH3.

Author: Encrenaz, T., Greathouse, T. K., Giles, R., Widemann, T., Bézard, B., Lefèvre, F., Lefèvre, M., Shao, W., Sagawa, H., Marcq, E., and Arredondo, A.
Subjects: NATURAL satellite atmospheres, INNER planets, SOUND recording & reproducing, PLANETARY atmospheres, VENUS (Planet)
Abstract: Aims. Following several reports announcing the detection or non-detection of minor species above the clouds of Venus, we have searched for other possible signatures of PH3, HCN, and NH3 in the infrared range. Methods. Since 2012, we have performed ground-based observations of Venus in the thermal infrared at various wavelengths to monitor the behavior of SO2 and H2O at the cloud top. We have identified spectral intervals where transitions of PH3 (around 955 cm−1), HCN (around 747 cm−1), and NH3 (around 951cm−1) are present. Results. From the absence of any feature at these frequencies, we derive, on the disk-integrated spectrum, a 3-σ upper limit of 3 ppbv for the PH3 mixing ratio, 0.5 ppbv for HCN, and 0.3 ppbv for NH3, assuming that these species have a constant mixing ratio throughout the atmosphere. Maps of the Venus disk recorded at the center position of the lines show that there is no evidence for local detection anywhere over the Venus disk. Conclusions. Our results bring new constraints on the maximum abundance of these species at the cloud top and in the lower mesosphere of Venus. [ABSTRACT FROM AUTHOR]
Published: 2024
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7. GEOCHEMISTRY OF SURFACE-ATMOSPHERE INTERACTIONS ON VENUS

Author: FEGLEY, B., primary, KLINGELHÖFER, G., additional, LODDERS, K., additional, and WIDEMANN, T., additional
Published: 2022
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8. Pluto's atmosphere from stellar occultations in 2012 and 2013

Author: Dias-Oliveira, A., Sicardy, B., Lellouch, E., Vieira-Martins, R., Assafin, M., Camargo, J. I. B., Braga-Ribas, F., Gomes-Júnior, A. R., Benedetti-Rossi, G., Colas, F., Decock, A., Doressoundiram, A., Dumas, C., Emilio, M., Polleri, J. Fabrega, Gil-Hutton, R., Gillon, M., Girard, J., Hau, G., Ivanov, V. D., Jehin, E., Lecacheux, J., Leiva, R., Lopez-Sisterna, C., Mancini, L., Maury, A., Meza, E., Morales, N., Nagy, L., Opitom, C., Ortiz, J. L., Pollock, J., Roques, F., Snodgrass, C., Soulier, J. F., Thirouin, A., Vanzi, L., Widemann, T., Reichart, D. E., LaCluyze, A. P., Haislip, J. B., Ivarsen, K. M., Dominik, M., Jørgensen, U., and Skottfelt, J.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: We analyze two multi-chord stellar occultations by Pluto observed on July 18th, 2012 and May 4th, 2013, and monitored respectively from five and six sites. They provide a total of fifteen light-curves, twelve of them being used for a simultaneous fit that uses a unique temperature profile, assuming a clear (no-haze) and pure N_2 atmosphere, but allowing for a possible pressure variation between the two dates. We find a solution that fits satisfactorily (i.e. within the noise level) all the twelve light-curves, providing atmospheric constraints between ~1,190 km (pressure ~ 11 \mubar) and ~ 1,450 km (pressure ~0.1 \mubar) from Pluto's center. Our main results are: (1) the best-fitting temperature profile shows a stratosphere with strong positive gradient between 1,190 km (at 36 K, 11 \mubar) and r = 1,215 km (6.0 \mubar), where a temperature maximum of 110 K is reached; above it is a mesosphere with negative thermal gradient of -0.2 K/km up to ~ 1,390 km (0.25 \mubar), where, the mesosphere connects itself to a more isothermal upper branch around 81 K; (2) the pressure shows a small (6 %) but significant increase (6-\sigma level) between the two dates; (3) without troposphere, Pluto's radius is found to be R_P = 1,190 +/- 5km. Allowing for a troposphere, R_P is constrained to lie between 1,168 and 1,195 km; (4) the currently measured CO abundance is too small to explain the mesospheric negative thermal gradient. Cooling by HCN is possible, but only if this species is largely saturated; Alternative explanations like zonal winds or vertical compositional variations of the atmosphere are unable to explain the observed mesospheric trend., Comment: 41 pages, 13 figures, 4 tables
Published: 2015
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9. 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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10. A ring system detected around the Centaur (10199) Chariklo

Author: Braga-Ribas, F., Sicardy, B., Ortiz, J. L., Snodgrass, C., Roques, F., Vieira-Martins, R., Camargo, J. I. B., Assafin, M., Duffard, R., Jehin, E., Pollock, J., Leiva, R., Emilio, M., Machado, D. I., Colazo, C., Lellouch, E., Skottfelt, J., Gillon, M., Ligier, N., Maquet, L., Benedetti-Rossi, G., Gomes Jr, A. Ramos, Kervella, P., Monteiro, H., Sfair, R., Moutamid, M. El, Tancredi, G., Spagnotto, J., Maury, A., Morales, N., Gil-Hutton, R., Roland, S., Ceretta, A., Gu, S. -h., Wang, X. -b., Harpsøe, K., Rabus, M., Manfroid, J., Opitom, C., Vanzi, L., Mehret, L., Lorenzini, L., Schneiter, E. M., Melia, R., Lecacheux, J., Colas, F., Vachier, F., Widemann, T., Almenares, L., Sandness, R. G., Char, F., Perez, V., Lemos, P., Martinez, N., Jørgensen, U. G., Dominik, M., Roig, F., Reichart, D. E., LaCluyze, A. P., Haislip, J. B., Ivarsen, K. M., Moore, J. P., Frank, N. R., and Lambas, D. G.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Until now, rings have been detected in the Solar System exclusively around the four giant planets. Here we report the discovery of the first minor-body ring system around the Centaur object (10199) Chariklo, a body with equivalent radius 124$\pm$9 km. A multi-chord stellar occultation revealed the presence of two dense rings around Chariklo, with widths of about 7 km and 3 km, optical depths 0.4 and 0.06, and orbital radii 391 and 405 km, respectively. The present orientation of the ring is consistent with an edge-on geometry in 2008, thus providing a simple explanation for the dimming of Chariklo's system between 1997 and 2008, and for the gradual disappearance of ice and other absorption features in its spectrum over the same period. This implies that the rings are partially composed of water ice. These rings may be the remnants of a debris disk, which were possibly confined by embedded kilometre-sized satellites.
Published: 2014
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11. World-leading science with SPIRou - the nIR spectropolarimeter / high-precision velocimeter for CFHT

Author: Delfosse, X., Donati, J. -F., Kouach, D., Hébrard, G., Doyon, R., Artigau, E., Bouchy, F., Boisse, I., Brun, A. S., Hennebelle, P., Widemann, T., Bouvier, J., Bonfils, X., Morin, J., Moutou, C., Pepe, F., Udry, S., Nascimento, J. -D. do, Alencar, S. H. P., Castilho, B. V., Martioli, E., Wang, S. Y., Figueira, P., Santos, N. C., and Team, the SPIRou Science
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
Abstract: SPIRou is a near-infrared (nIR) spectropolarimeter / velocimeter proposed as a new-generation instrument for CFHT. SPIRou aims in particular at becoming world-leader on two forefront science topics, (i) the quest for habitable Earth-like planets around very- low-mass stars, and (ii) the study of low-mass star and planet formation in the presence of magnetic fields. In addition to these two main goals, SPIRou will be able to tackle many key programs, from weather patterns on brown dwarf to solar-system planet atmospheres, to dynamo processes in fully-convective bodies and planet habitability. The science programs that SPIRou proposes to tackle are forefront (identified as first priorities by most research agencies worldwide), ambitious (competitive and complementary with science programs carried out on much larger facilities, such as ALMA and JWST) and timely (ideally phased with complementary space missions like TESS and CHEOPS). SPIRou is designed to carry out its science mission with maximum efficiency and optimum precision. More specifically, SPIRou will be able to cover a very wide single-shot nIR spectral domain (0.98-2.35 \mu m) at a resolving power of 73.5K, providing unpolarized and polarized spectra of low-mass stars with a ~15% average throughput and a radial velocity (RV) precision of 1 m/s., Comment: 12 pages, 5 figures, conference proceedings of the French Society of Astronomy and Astrophysics meeting 2013
Published: 2013

12. Instrumental Methods for Professional and Amateur Collaborations in Planetary Astronomy

Author: Mousis, O., Hueso, R., Beaulieu, J. -P., Bouley, S., Carry, B., Colas, F., Klotz, A., Pellier, C., Petit, J. -M., Rousselot, P., Dib, M. Ali, Beisker, W., Birlan, M., Buil, C., Delsanti, A., Frappa, E., Hammel, H. B., Levasseur-Regourd, A. -C., Orton, G. S., Sanchez-Lavega, A., Santerne, A., Tanga, P., Vaubaillon, J., Zanda, B., Baratoux, D., Boehm, T., Boudon, V., Bouquet, A., Buzzi, L., Dauvergne, J. -L., Decock, A., Delcroix, M., Drossart, P., Esseiva, N., Fischer, G., Fletcher, L. N., Foglia, S., Gomez-Forrellad, J. M., Guarro-Flo, J., Herald, D., Jehin, E., Kugel, F., Lebreton, J. -P., Lecacheux, J., Leroy, A., Maquet, L., Masi, G., Maury, A., Meyer, F., Pérez-Hoyos, S., Rajpurohit, A. S., Rinner, C., Rogers, J. H., Roques, F., Schmude, Jr., R. W., Sicardy, B., Tregon, B., Vanhuysse, M., Wesley, A., and Widemann, T.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Amateur contributions to professional publications have increased exponentially over the last decades in the field of Planetary Astronomy. Here we review the different domains of the field in which collaborations between professional and amateur astronomers are effective and regularly lead to scientific publications. We discuss the instruments, detectors, softwares and methodologies typically used by amateur astronomers to collect the scientific data in the different domains of interest. Amateur contributions to the monitoring of planets and interplanetary matter, characterization of asteroids and comets, as well as the determination of the physical properties of Kuiper Belt Objects and exoplanets are discussed., Comment: 123 pages, Accepted for publication in Experimental Astronomy
Published: 2013
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13. EChO - Exoplanet Characterisation Observatory

Author: Tinetti, G., Beaulieu, J. P., Henning, T., Meyer, M., Micela, G., Ribas, I., Stam, D., Swain, M., Krause, O., Ollivier, M., Pace, E., Swinyard, B., Aylward, A., van Boekel, R., Coradini, A., Encrenaz, T., Snellen, I., Zapatero-Osorio, M. R., Bouwman, J., Cho, J. Y-K., Foresto, V. Coudé du, Guillot, T., Lopez-Morales, M., Mueller-Wodarg, I., Palle, E., Selsis, F., Sozzetti, A., Ade, P. A. R., Achilleos, N., Adriani, A., Agnor, C. B., Afonso, C., Prieto, C. Allende, Bakos, G., Barber, R. J., Barlow, M., Bernath, P., Bezard, B., Bordé, P., Brown, L. R., Cassan, A., Cavarroc, C., Ciaravella, A., Cockell, C. O. U., Coustenis, A., Danielski, C., Decin, L., De Kok, R., Demangeon, O., Deroo, P., Doel, P., Drossart, P., Fletcher, L. N., Focardi, M., Forget, F., Fossey, S., Fouqué, P., Frith, J., Galand, M., Gaulme, P., Hernández, J. I. González, Grasset, O., Grassi, D., Grenfell, J. L., Griffin, M. J., Griffith, C. A., Grözinger, U., Guedel, M., Guio, P., Hainaut, O., Hargreaves, R., Hauschildt, P. H., Heng, K., Heyrovsky, D., Hueso, R., Irwin, P., Kaltenegger, L., Kervella, P., Kipping, D., Koskinen, T. T., Kovács, G., La Barbera, A., Lammer, H., Lellouch, E., Leto, G., Morales, M. Lopez, Valverde, M. A. Lopez, Lopez-Puertas, M., Lovis, C., Maggio, A., Maillard, J. P., Prado, J. Maldonado, Marquette, J. B., Martin-Torres, F. J., Maxted, P., Miller, S., Molinari, S., Montes, D., Moro-Martin, A., Moses, J. I., Mousis, O., Tuong, N. Nguyen, Nelson, R., Orton, G. S., Pantin, E., Pascale, E., Pezzuto, S., Pinfield, D., Poretti, E., Prinja, R., Prisinzano, L., Rees, J. M., Reiners, A., Samuel, B., Sanchez-Lavega, A., Forcada, J. Sanz, Sasselov, D., Savini, G., Sicardy, B., Smith, A., Stixrude, L., Strazzulla, G., Tennyson, J., Tessenyi, M., Vasisht, G., Vinatier, S., Viti, S., Waldmann, I., White, G. J., Widemann, T., Wordsworth, R., Yelle, R., Yung, Y., and Yurchenko, S. N.
Subjects: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context and by addressing the suitability of planets for the presence of life. EChO -the Exoplanet Characterisation Observatory- is a mission concept specifically geared for this purpose. EChO will provide simultaneous, multi-wavelength spectroscopic observations on a stable platform that will allow very long exposures. EChO will build on observations by Hubble, Spitzer and groundbased telescopes, which discovered the first molecules and atoms in exoplanetary atmospheres. EChO will simultaneously observe a broad enough spectral region -from the visible to the mid-IR- to constrain from one single spectrum the temperature structure of the atmosphere and the abundances of the major molecular species. The spectral range and resolution are tailored to separate bands belonging to up to 30 molecules to retrieve the composition and temperature structure of planetary atmospheres. The target list for EChO includes planets ranging from Jupiter-sized with equilibrium temperatures Teq up to 2000 K, to those of a few Earth masses, with Teq ~300 K. We have baselined a dispersive spectrograph design covering continuously the 0.4-16 micron spectral range in 6 channels (1 in the VIS, 5 in the IR), which allows the spectral resolution to be adapted from several tens to several hundreds, depending on the target brightness. The instrument will be mounted behind a 1.5 m class telescope, passively cooled to 50 K, with the instrument structure and optics passively cooled to ~45 K. EChO will be placed in a grand halo orbit around L2. We have also undertaken a first-order cost and development plan analysis and find that EChO is easily compatible with the ESA M-class mission framework., Comment: Accepted for publication in Experimental Astronomy, 23 pages, 15 figures
Published: 2011
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14. Venus wind map at cloud top level with the MTR/THEMIS visible spectrometer. I. Instrumental performance and first results

Author: Gaulme, P., Schmider, F. -X, Grec, C., Ariste, A. Lopez, Widemann, T., and Gelly, B.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Solar light gets scattered at cloud top level in Venus' atmosphere, in the visible range, which corresponds to the altitude of 67 km. We present Doppler velocity measurements performed with the high resolution spectrometer MTR of the Solar telescope THEMIS (Teide Observatory, Canary Island) on the sodium D2 solar line (5890 \AA). Observations lasted only 49 min because of cloudy weather. However, we could assess the instrumental velocity sensitivity, 31 m/s per pixel of 1 arcsec, and give a value of the amplitude of zonal wind at equator at 151 +/- 16 m/s., Comment: 17 pages, 12 figures
Published: 2010
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15. HDO and SO2 thermal mapping on Venus

Author: Encrenaz, T., primary, Greathouse, T. K., additional, Giles, R., additional, Widemann, T., additional, Bézard, B., additional, Lefèvre, M., additional, and Shao, W., additional
Published: 2023
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16. A sub-Neptune planet around TOI-1695 discovered and characterized with SPIRou and TESS

Author: Kiefer, F., primary, Hébrard, G., additional, Martioli, E., additional, Artigau, E., additional, Doyon, R., additional, Donati, J.-F., additional, Cadieux, C., additional, Carmona, A., additional, Ciardi, D. R., additional, Cristofari, P. I., additional, de Almeida, L., additional, Figueira, P., additional, Gaidos, E., additional, Gonzales, E., additional, Lecavelier Des Etangs, A., additional, Stassun, K. G., additional, Arnold, L., additional, Benneke, B., additional, Boisse, I., additional, Bonfils, X., additional, Cook, N. J., additional, Cortés-Zuleta, P., additional, Delfosse, X., additional, do Nascimento, J. Dias, additional, Fausnaugh, M., additional, Fong, W., additional, Fouqué, P., additional, Forveille, T., additional, Gomes da Silva, J., additional, Hesse, K., additional, Kóspál, Á., additional, Lewis, H., additional, Liu, C.-F., additional, Martins, J. H. C., additional, Paegert, M., additional, Seager, S., additional, Shang, H., additional, Twicken, J. D., additional, Vandal, T., additional, Vinatier, S., additional, Widemann, T., additional, and Winn, J. N., additional
Published: 2023
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17. The Venus Emissivity Mapper: implementation for flight on the NASA VERITAS mission

Author: Helbert, Jörn, Pertenais, Martin, Walter, Ingo, Peter, Gisbert, Säuberlich, Thomas, Cacovean, Andrei, Maturilli, Alessandro, Alemanno, Giulia, zender, bernd, Arcos Carrasco, C., Dern, Patrick, Pohl, Andreas, Del Togno, Simone, Rockstein, Steve, Rosas-Ortiz, Yaquelin, Rufini Mastropasqua, S, Wendler, Dennis, Westerdorff, Karsten, Reess, J. M., Pechevis, E, Jerome, C, Buey, J.~T., Widemann, T., Behnke, Thomas, Wolff, Friederike, Adeli, Solmaz, Amore, Mario, and Dyar, Darby
Subjects: instrument, Spektroskopie, Venus, sensorik
Published: 2022

18. VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy): A Selected Discovery Mission

Author: Smrekar, S.E., Hensley, Scott, Dyar, M. D., Whitten, J., Nunes, Daniel, Helbert, Jörn, Iess, L., Mazerico, E., Andrews-Hanna, Jeff, Breuer, Doris, Buczkowski, D.L., Campbell, B.A., Davaille, Ann, DiAchille, G., Fassett, C, Gilmore, M., Herrick, Robbie, Jozwiak, L. M., Kataria, T, Konopliv, A., Mastrogiuseppe, M, Müller, Nils, Raguso, Maria, Stock, Joanna, Stofan, E. R., Tsang, C. C. C., Widemann, T., and Zebker, Howard
Subjects: Radar, VERITAS, Spektroskopie, Venus
Published: 2022

19. The Venus Surface Emissivity Mapper on the NASA VERITAS Mission and the VenSpec Suite on the ESA EnVision Mission

Author: Helbert, Jörn, Dyar, M. D., Vandaele, A. C., Marcq, E., Mueller, N, Alemanno, Giulia, Maturilli, Alessandro, Widemann, T., and Smrekar, S.
Subjects: mission, envision, venus, exploration
Published: 2022

20. Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

Author: Física aplicada I, Fisika aplikatua I, Marques Oliveira, Joana, Sicardy, Bruno, Gómes Junior, A.R., Ortiz, J.L., Strobel, D.F., Bertrand, T., Forget, F., Lellouch, E., Desmars, J., Bérard, D., Doressoundiram, A., Lecacheux, J., Leiva, R., Meza, E., Roques, F., Souami, D., Widemann, T., Santos Sanz, Pablo, Morales, N., Duffard, Rene, Fernández Valenzuela, Estela, Castro Tirado, A.J., Braga Ribas, Felipe, Morgado, Bruno, Assafin, Marcelo, Bueno de Camargo, Julio Ignacio, Vieira Martins, Roberto, Benedetti Rossi, Gustavo, Santos Filho, S., Banda Huarca, M.V., Quispe Huaynasi, F., Pereira, Chrystian Luciano, Rommel, Flavia Luane, Margoti, Giuliano, Dias Oliveira, A., Colas, F., Berthier, J., Renner, S., Hueso, Ricardo, Pérez Hoyos, Santiago, Sánchez Lavega, Agustín María, Rojas Palenzuela, José Félix, Beisker, W., Kretlow, Mike, Herald, D., Gault, D., Bath, K.-L., Bode, H.-J., Bredner, E., Guhl, K., Haymes, T.V., Hummel, E., Kattentidt, B., Klös, O., Pratt, A., Thome, B., Avdellidou, Chrysa, Gazeas, K., Karampotsiou, E., Tzouganatos, L., Kardasis, E., Christou, A.A., Xilouris, Emmanuel, Alikakos, I., Gourzelas, A., Liakos, Alexios, Charmandaris, Vassilis, Jelínek, Martin, Štrobl, Jan, Eberle, A., Rapp, K., Gährken, B., Klemt, B., Kowollik, S., Bitzer, R., Miller, M., Herzogenrath, G., Frangenberg, Dirk, Brandis, L., Pütz, I., Perdelwitz, Volker, Piehler, G. M., Riepe, P., von Poschinger, K., Baruffetti, P., Cenadelli, D., Christille, J.-M., Ciabattari, F., Di Luca, R., Alboresi, D., Leto, Giuseppe, Zanmar Sánchez, R., Bruno, P., Occhipinti, G., Morrone, L., Cupolino, L., Noschese, A., Vecchione, A., Scalia, Cesare, Lo Savio, R., Giardina, G., Kamoun, S., Barbosa, R., Behrend, R., Spano, M., Bouchet, E., Cottier, M., Falco, L., G. Gallego, Sofía, Tortorelli, Luca, Sposetti, S., Sussenbach, J., Van Den Abbeel, F., André, P., Llibre, M., Pailler, Frédéric, Ardissone, J., Boutet, Michel, Sánchez, J., Bretton, M., Cailleau, A., Pic, V., Granier, L., Chauvet, R., Conjat, M., Dauvergne, J.L., Dechambre, O., Delay, P., Delcroix, Marc, Rousselot, Lionel, Ferreira, João, Machado, Pedro, Tanga, P., Rivet, J.-P., Frappa, Eric, Irzyk, M., Jabet, F., Kaschinski, M., Klotz, A., Rieugnie, Y., Klotz, A.N., Labrevoir, O., Lavandier, D., Walliang, D., Leroy, A., Bouley, S., Lisciandra, S., Coliac, Jean-François, Metz, F., Erpelding, D., Nougayrede, Jean-Philippe, Midavaine, T., Miniou, M., Moindrot, S., Morel, P., Reginato, B., Reginato, E., Rudelle, J., Tregon, B., Tanguy, R., David, J., Thuillot, W., Hestroffer, D., Vaudescal, G., Baba Aissa, D., Grigahcene, Z., Briggs, D., Broadbent, Stephen, Denyer, P., Haigh, Nicholas, Quinn, N., Thurston, G., Fossey, S. J., Arena, C., Jennings, M., talbot, J., Alonso Burgos, Sergio, Román Reche, A., Casanova, V., Briggs, E., Iglesias Marzoa, Ramón, Abril Ibáñez, J., Díaz Martín, M.C., González, H., Maestre García, J.L., Marchant, Jonathan, Ordoñez Etxeberria, Iñaki, Martorell, P., Salamero, J., Organero, F., Ana, L., Fonseca, F., Peris, V., Brevia, O., Selva, A., Perelló Pérez, Carlos, Cabedo, V., Gonçalves, Rui M. D., Ferreira, M., Marques Dias, Filipe, Daassou, A., Barkaoui, Khalid, Benkhaldoun, Z., Guennoun, M., Chouqar, J., Jehin, E., Rinner, C., Lloyd, J., El Moutamid, Maryame, Lamarche, C., Pollock, J.T., caton, D.B., Kouprianov, Vladimir, Timerson, B.W., Blanchard, G., Payet, B., Peyrot, A., Teng-Chuen-Yu, J.-P., Françoise, J., Mondon, Bernard, Payet, Thierry, Boissel, C., Castets, M., Hubbard, William, Hill, R., Reitsema, H. J., Mousis, Olivier, Ball, L., Neilsen, G., Hutcheon, S., lay, K., Anderson, P., Moy, M., Jonsen, M., Pink, I., Walters, R., Downs, B., Física aplicada I, Fisika aplikatua I, Marques Oliveira, Joana, Sicardy, Bruno, Gómes Junior, A.R., Ortiz, J.L., Strobel, D.F., Bertrand, T., Forget, F., Lellouch, E., Desmars, J., Bérard, D., Doressoundiram, A., Lecacheux, J., Leiva, R., Meza, E., Roques, F., Souami, D., Widemann, T., Santos Sanz, Pablo, Morales, N., Duffard, Rene, Fernández Valenzuela, Estela, Castro Tirado, A.J., Braga Ribas, Felipe, Morgado, Bruno, Assafin, Marcelo, Bueno de Camargo, Julio Ignacio, Vieira Martins, Roberto, Benedetti Rossi, Gustavo, Santos Filho, S., Banda Huarca, M.V., Quispe Huaynasi, F., Pereira, Chrystian Luciano, Rommel, Flavia Luane, Margoti, Giuliano, Dias Oliveira, A., Colas, F., Berthier, J., Renner, S., Hueso, Ricardo, Pérez Hoyos, Santiago, Sánchez Lavega, Agustín María, Rojas Palenzuela, José Félix, Beisker, W., Kretlow, Mike, Herald, D., Gault, D., Bath, K.-L., Bode, H.-J., Bredner, E., Guhl, K., Haymes, T.V., Hummel, E., Kattentidt, B., Klös, O., Pratt, A., Thome, B., Avdellidou, Chrysa, Gazeas, K., Karampotsiou, E., Tzouganatos, L., Kardasis, E., Christou, A.A., Xilouris, Emmanuel, Alikakos, I., Gourzelas, A., Liakos, Alexios, Charmandaris, Vassilis, Jelínek, Martin, Štrobl, Jan, Eberle, A., Rapp, K., Gährken, B., Klemt, B., Kowollik, S., Bitzer, R., Miller, M., Herzogenrath, G., Frangenberg, Dirk, Brandis, L., Pütz, I., Perdelwitz, Volker, Piehler, G. M., Riepe, P., von Poschinger, K., Baruffetti, P., Cenadelli, D., Christille, J.-M., Ciabattari, F., Di Luca, R., Alboresi, D., Leto, Giuseppe, Zanmar Sánchez, R., Bruno, P., Occhipinti, G., Morrone, L., Cupolino, L., Noschese, A., Vecchione, A., Scalia, Cesare, Lo Savio, R., Giardina, G., Kamoun, S., Barbosa, R., Behrend, R., Spano, M., Bouchet, E., Cottier, M., Falco, L., G. Gallego, Sofía, Tortorelli, Luca, Sposetti, S., Sussenbach, J., Van Den Abbeel, F., André, P., Llibre, M., Pailler, Frédéric, Ardissone, J., Boutet, Michel, Sánchez, J., Bretton, M., Cailleau, A., Pic, V., Granier, L., Chauvet, R., Conjat, M., Dauvergne, J.L., Dechambre, O., Delay, P., Delcroix, Marc, Rousselot, Lionel, Ferreira, João, Machado, Pedro, Tanga, P., Rivet, J.-P., Frappa, Eric, Irzyk, M., Jabet, F., Kaschinski, M., Klotz, A., Rieugnie, Y., Klotz, A.N., Labrevoir, O., Lavandier, D., Walliang, D., Leroy, A., Bouley, S., Lisciandra, S., Coliac, Jean-François, Metz, F., Erpelding, D., Nougayrede, Jean-Philippe, Midavaine, T., Miniou, M., Moindrot, S., Morel, P., Reginato, B., Reginato, E., Rudelle, J., Tregon, B., Tanguy, R., David, J., Thuillot, W., Hestroffer, D., Vaudescal, G., Baba Aissa, D., Grigahcene, Z., Briggs, D., Broadbent, Stephen, Denyer, P., Haigh, Nicholas, Quinn, N., Thurston, G., Fossey, S. J., Arena, C., Jennings, M., talbot, J., Alonso Burgos, Sergio, Román Reche, A., Casanova, V., Briggs, E., Iglesias Marzoa, Ramón, Abril Ibáñez, J., Díaz Martín, M.C., González, H., Maestre García, J.L., Marchant, Jonathan, Ordoñez Etxeberria, Iñaki, Martorell, P., Salamero, J., Organero, F., Ana, L., Fonseca, F., Peris, V., Brevia, O., Selva, A., Perelló Pérez, Carlos, Cabedo, V., Gonçalves, Rui M. D., Ferreira, M., Marques Dias, Filipe, Daassou, A., Barkaoui, Khalid, Benkhaldoun, Z., Guennoun, M., Chouqar, J., Jehin, E., Rinner, C., Lloyd, J., El Moutamid, Maryame, Lamarche, C., Pollock, J.T., caton, D.B., Kouprianov, Vladimir, Timerson, B.W., Blanchard, G., Payet, B., Peyrot, A., Teng-Chuen-Yu, J.-P., Françoise, J., Mondon, Bernard, Payet, Thierry, Boissel, C., Castets, M., Hubbard, William, Hill, R., Reitsema, H. J., Mousis, Olivier, Ball, L., Neilsen, G., Hutcheon, S., lay, K., Anderson, P., Moy, M., Jonsen, M., Pink, I., Walters, R., and Downs, B.
Abstract: Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range similar to 8 km to similar to 190 km, corresponding to pressure levels from 9 mu bar down to a few nanobars. Results. (i) A pressure of 1.18 +/- 0.03 mu bar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 mu bar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude.
Published: 2022

21. Sunlight refraction in the mesosphere of Venus during the transit on June 8th, 2004

Author: Tanga, P., Widemann, T., Sicardy, B., Pasachoff, J.M., Arnaud, J., Comolli, L., Rondi, A., Rondi, S., and Sütterlin, P.
Published: 2012
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22. Constraints on the structure and seasonal variations of Triton’s atmosphere from the 5 October 2017 stellar occultation and previous observations

Author: Marques Oliveira, J., primary, Sicardy, B., additional, Gomes-Júnior, A. R., additional, Ortiz, J. L., additional, Strobel, D. F., additional, Bertrand, T., additional, Forget, F., additional, Lellouch, E., additional, Desmars, J., additional, Bérard, D., additional, Doressoundiram, A., additional, Lecacheux, J., additional, Leiva, R., additional, Meza, E., additional, Roques, F., additional, Souami, D., additional, Widemann, T., additional, Santos-Sanz, P., additional, Morales, N., additional, Duffard, R., additional, Fernández-Valenzuela, E., additional, Castro-Tirado, A. J., additional, Braga-Ribas, F., additional, Morgado, B. E., additional, Assafin, M., additional, Camargo, J. I. B., additional, Vieira-Martins, R., additional, Benedetti-Rossi, G., additional, Santos-Filho, S., additional, Banda-Huarca, M. V., additional, Quispe-Huaynasi, F., additional, Pereira, C. L., additional, Rommel, F. L., additional, Margoti, G., additional, Dias-Oliveira, A., additional, Colas, F., additional, Berthier, J., additional, Renner, S., additional, Hueso, R., additional, Pérez-Hoyos, S., additional, Sánchez-Lavega, A., additional, Rojas, J. F., additional, Beisker, W., additional, Kretlow, M., additional, Herald, D., additional, Gault, D., additional, Bath, K.-L., additional, Bode, H.-J., additional, Bredner, E., additional, Guhl, K., additional, Haymes, T. V., additional, Hummel, E., additional, Kattentidt, B., additional, Klös, O., additional, Pratt, A., additional, Thome, B., additional, Avdellidou, C., additional, Gazeas, K., additional, Karampotsiou, E., additional, Tzouganatos, L., additional, Kardasis, E., additional, Christou, A. A., additional, Xilouris, E. M., additional, Alikakos, I., additional, Gourzelas, A., additional, Liakos, A., additional, Charmandaris, V., additional, Jelínek, M., additional, Štrobl, J., additional, Eberle, A., additional, Rapp, K., additional, Gährken, B., additional, Klemt, B., additional, Kowollik, S., additional, Bitzer, R., additional, Miller, M., additional, Herzogenrath, G., additional, Frangenberg, D., additional, Brandis, L., additional, Pütz, I., additional, Perdelwitz, V., additional, Piehler, G. M., additional, Riepe, P., additional, von Poschinger, K., additional, Baruffetti, P., additional, Cenadelli, D., additional, Christille, J.-M., additional, Ciabattari, F., additional, Di Luca, R., additional, Alboresi, D., additional, Leto, G., additional, Zanmar Sanchez, R., additional, Bruno, P., additional, Occhipinti, G., additional, Morrone, L., additional, Cupolino, L., additional, Noschese, A., additional, Vecchione, A., additional, Scalia, C., additional, Lo Savio, R., additional, Giardina, G., additional, Kamoun, S., additional, Barbosa, R., additional, Behrend, R., additional, Spano, M., additional, Bouchet, E., additional, Cottier, M., additional, Falco, L., additional, Gallego, S., additional, Tortorelli, L., additional, Sposetti, S., additional, Sussenbach, J., additional, Van Den Abbeel, F., additional, André, P., additional, Llibre, M., additional, Pailler, F., additional, Ardissone, J., additional, Boutet, M., additional, Sanchez, J., additional, Bretton, M., additional, Cailleau, A., additional, Pic, V., additional, Granier, L., additional, Chauvet, R., additional, Conjat, M., additional, Dauvergne, J. L., additional, Dechambre, O., additional, Delay, P., additional, Delcroix, M., additional, Rousselot, L., additional, Ferreira, J., additional, Machado, P., additional, Tanga, P., additional, Rivet, J.-P., additional, Frappa, E., additional, Irzyk, M., additional, Jabet, F., additional, Kaschinski, M., additional, Klotz, A., additional, Rieugnie, Y., additional, Klotz, A. N., additional, Labrevoir, O., additional, Lavandier, D., additional, Walliang, D., additional, Leroy, A., additional, Bouley, S., additional, Lisciandra, S., additional, Coliac, J.-F., additional, Metz, F., additional, Erpelding, D., additional, Nougayrède, P., additional, Midavaine, T., additional, Miniou, M., additional, Moindrot, S., additional, Morel, P., additional, Reginato, B., additional, Reginato, E., additional, Rudelle, J., additional, Tregon, B., additional, Tanguy, R., additional, David, J., additional, Thuillot, W., additional, Hestroffer, D., additional, Vaudescal, G., additional, Baba Aissa, D., additional, Grigahcene, Z., additional, Briggs, D., additional, Broadbent, S., additional, Denyer, P., additional, Haigh, N. J., additional, Quinn, N., additional, Thurston, G., additional, Fossey, S. J., additional, Arena, C., additional, Jennings, M., additional, Talbot, J., additional, Alonso, S., additional, Román Reche, A., additional, Casanova, V., additional, Briggs, E., additional, Iglesias-Marzoa, R., additional, Abril Ibáñez, J., additional, Díaz Martín, M. C., additional, González, H., additional, Maestre García, J. L., additional, Marchant, J., additional, Ordonez-Etxeberria, I., additional, Martorell, P., additional, Salamero, J., additional, Organero, F., additional, Ana, L., additional, Fonseca, F., additional, Peris, V., additional, Brevia, O., additional, Selva, A., additional, Perello, C., additional, Cabedo, V., additional, Gonçalves, R., additional, Ferreira, M., additional, Marques Dias, F., additional, Daassou, A., additional, Barkaoui, K., additional, Benkhaldoun, Z., additional, Guennoun, M., additional, Chouqar, J., additional, Jehin, E., additional, Rinner, C., additional, Lloyd, J., additional, El Moutamid, M., additional, Lamarche, C., additional, Pollock, J. T., additional, Caton, D. B., additional, Kouprianov, V., additional, Timerson, B. W., additional, Blanchard, G., additional, Payet, B., additional, Peyrot, A., additional, Teng-Chuen-Yu, J.-P., additional, Françoise, J., additional, Mondon, B., additional, Payet, T., additional, Boissel, C., additional, Castets, M., additional, Hubbard, W. B., additional, Hill, R., additional, Reitsema, H. J., additional, Mousis, O., additional, Ball, L., additional, Neilsen, G., additional, Hutcheon, S., additional, Lay, K., additional, Anderson, P., additional, Moy, M., additional, Jonsen, M., additional, Pink, I., additional, Walters, R., additional, and Downs, B., additional
Published: 2022
Full Text: View/download PDF

23. VizieR Online Data Catalog: Triton light curves from 05/10/2017 (Marques Oliveira+, 2022)

Author: Marques Oliveira, J., Sicardy, B., Gomes-Junior, A. R., Ortiz, J. L., Strobel, D. F., Bertrand, T., Forget, F., Lellouch, E., Desmars, J., Berard, D., Doressoundiram, A., Lecacheux, J., Leiva, R., Meza, E., Roques, F., Souami, D., Widemann, T., Santos-Sanz, P., Morales, N., Duffard, R., Fernandez-Valenzuela, E., Castro-Tirado, A. J., Braga-Ribas, F., Morgado, B. E., Assafin, M., Camargo, J. I. B., Vieira-Martins, R., Benedetti-Rossi, G., Santos-Filho, S., Banda-Huarca, M. V., Quispe-Huaynasi, F., Pereira, C. L., Rommel, F. L., Margoti, G., Dias-Oliveira, A., Colas, F., Berthier, J., Renner, S., Hueso, R., Perez-Hoyos, S., Sanchez-Lavega, A., Rojas, J. F., Beisker, W., Kretlow, M., Herald, D., Gault, D., Bath, K.-L., Bode, H.-J., Bredner, E., Guhl, K., Haymes, T. V., Hummel, E., Kattentidt, B., Klos, O., Pratt, A., Thome, B., Avdellidou, C., Gazeas, K., Karampotsiou, E., Tzouganatos, L., Kardasis, E., Christou, A. A., Xilouris, E. M., Alikakos, I., Gourzelas, A., Liakos, A., Charmandaris, V., Jelinek, M., Strobl, J., Eberle, A., Rapp, K., Gahrken, B., Kowo Llik, S., Bitzer, R., Miller, M., Herzogenrath, G., Frangenberg, D., Brandis, L., Puetz, I., Perdelwitz, V., Piehler, G. M., Riepe, P., von Poschinger, K., Baruffetti, P., Cenadelli, D., Christille, J.-M., Ciabattari, F., Di, Luca R., Alboresi, D., Leto, G., Zanmar Sanchez, R., Bruno, P., Occhipinti, G., Morrone, L., Cupolino, L., Noschese, A., Vecchione, A., Scalia, C., Lo Savio, R., Giardina, G., Kamoun, S., Barbosa, R., Behrend, R., Spano, M., Bouchet, E., Cottier, M., Falco, L., Gallego, S., Tortorelli, L., Sposetti, S., Sussenbach, J., van den Abbeel, F., Andre, P., Llibre, M., Pailler, F., Ardissone, J., Boutet, M., Sanchez, J., Bretton, M., Cailleau, A., Pic, V., Granier, L., Chauvet, R., Conjat, M., Dauvergne, J. L., Dechambre, O., Delay, P., Delcroix, M., Rousselot, L., Ferreira, J., Machado, P., Tanga, P., Rivet, J.-P., Frappa, E., Irzyk, M., Jabet, F., Kaschinski, M., Klotz, A., Rieugnie, Y., Klotz, A. N., Labrevoir, O., Lavandier, D., Walliang, D., Leroy, A., Bouley, S., Lisciandra, S., Coliac, J.-F., Metz, F., Erpelding, D., Nougayrede, P., Miniou, M., Moindrot, S., Morel, P., Reginato, B., Reginato, E., Rudelle, J., Tregon, B., Tanguy, R., David, J., Thuillot, W., Hestroffer, D., Vaudescal, G., Baba Aissa, D., Grigahcene, Z., Briggs, D., Broadbent, S., Denyer, P., Haigh, N. J., Quinn, N., Thurston, G., Fossey, S. J., Arena, C., Jennings, M., Talbot, J., Alonso, S., Roman Reche, A., Casanova, V., Briggs, E., Iglesias-Marzoa, R., Abril Ibanez, J., Diaz, Martin M. C., Gonzalez, H., Maestre Garcia, J. L., Marchant, J., Ordonez-Etxeberria, I., Martorell, P., Salamero, J., Organero, F., Ana, L., Fonseca, F., Peris, V., Brevia, O., Selva, A., Perello, C., Cabedo, V., Goncalves, R., Ferreira, M., Marques Dias, F., Daassou, A., Barkaoui, K., Benkhaldoun, Z., Guennoun, M., Chouqar, J., Jehin, E., Rinner, C., Lloyd, J., El Moutamid, M., Lamarche, C., Pollock, J. T., Caton, D. B., Kouprianov, V., Timerson, B. W., Blanchard, G., Payet, B., Peyrot, A., Teng-Chuen-Yu, J.-P., Francoise, J., Mondon, B., Payet, T., Boissel, C., Castets, M., Hubbard, W. B., Hill, R., Reitsema, H. J., Mousis, O., Ball, L., Hutcheon, S., Lay, K., Anderson, P., Moy, M., Jonsen, M., Pink, I., Walters, R., Downs, B., Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Photometry, Planets, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Solar system
Abstract: International audience; The data provided features all light curves from the 5 October 2017 event. The names of the files are the same names, in lower caps and with no spaces, that are presented in Figures C.1 and C.2. The first column of all files is the time in seconds, starting on 5 October 2017 00:00:00 UTC. The second column of all files is the normalised flux, where the unocculted flux oscillates around 1. (2 data files).
Published: 2022

24. Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations

Author: Marques Oliveira, J. Sicardy, B. Gomes-Júnior, A.R. Ortiz, J.L. Strobel, D.F. Bertrand, T. Forget, F. Lellouch, E. Desmars, J. Bérard, D. Doressoundiram, A. Lecacheux, J. Leiva, R. Meza, E. Roques, F. Souami, D. Widemann, T. Santos-Sanz, P. Morales, N. Duffard, R. Fernández-Valenzuela, E. Castro-Tirado, A.J. Braga-Ribas, F. Morgado, B.E. Assafin, M. Camargo, J.I.B. Vieira-Martins, R. Benedetti-Rossi, G. Santos-Filho, S. Banda-Huarca, M.V. Quispe-Huaynasi, F. Pereira, C.L. Rommel, F.L. Margoti, G. Dias-Oliveira, A. Colas, F. Berthier, J. Renner, S. Hueso, R. Pérez-Hoyos, S. Sánchez-Lavega, A. Rojas, J.F. Beisker, W. Kretlow, M. Herald, D. Gault, D. Bath, K.-L. Bode, H.-J. Bredner, E. Guhl, K. Haymes, T.V. Hummel, E. Kattentidt, B. Klös, O. Pratt, A. Thome, B. Avdellidou, C. Gazeas, K. Karampotsiou, E. Tzouganatos, L. Kardasis, E. Christou, A.A. Xilouris, E.M. Alikakos, I. Gourzelas, A. Liakos, A. Charmandaris, V. Jelínek, M. Štrobl, J. Eberle, A. Rapp, K. Gährken, B. Klemt, B. Kowollik, S. Bitzer, R. Miller, M. Herzogenrath, G. Frangenberg, D. Brandis, L. Pütz, I. Perdelwitz, V. Piehler, G.M. Riepe, P. Von Poschinger, K. Baruffetti, P. Cenadelli, D. Christille, J.-M. Ciabattari, F. Di Luca, R. Alboresi, D. Leto, G. Zanmar Sanchez, R. Bruno, P. Occhipinti, G. Morrone, L. Cupolino, L. Noschese, A. Vecchione, A. Scalia, C. Lo Savio, R. Giardina, G. Kamoun, S. Barbosa, R. Behrend, R. Spano, M. Bouchet, E. Cottier, M. Falco, L. Gallego, S. Tortorelli, L. Sposetti, S. Sussenbach, J. Van Den Abbeel, F. André, P. Llibre, M. Pailler, F. Ardissone, J. Boutet, M. Sanchez, J. Bretton, M. Cailleau, A. Pic, V. Granier, L. Chauvet, R. Conjat, M. Dauvergne, J.L. Dechambre, O. Delay, P. Delcroix, M. Rousselot, L. Ferreira, J. MacHado, P. Tanga, P. Rivet, J.-P. Frappa, E. Irzyk, M. Jabet, F. Kaschinski, M. Klotz, A. Rieugnie, Y. Klotz, A.N. Labrevoir, O. Lavandier, D. Walliang, D. Leroy, A. Bouley, S. Lisciandra, S. Coliac, J.-F. Metz, F. Erpelding, D. Nougayrède, P. Midavaine, T. Miniou, M. Moindrot, S. Morel, P. Reginato, B. Reginato, E. Rudelle, J. Tregon, B. Tanguy, R. David, J. Thuillot, W. Hestroffer, D. Vaudescal, G. Baba Aissa, D. Grigahcene, Z. Briggs, D. Broadbent, S. Denyer, P. Haigh, N.J. Quinn, N. Thurston, G. Fossey, S.J. Arena, C. Jennings, M. Talbot, J. Alonso, S. Román Reche, A. Casanova, V. Briggs, E. Iglesias-Marzoa, R. Abril Ibáñez, J. Díaz Martín, M.C. González, H. Maestre García, J.L. Marchant, J. Ordonez-Etxeberria, I. Martorell, P. Salamero, J. Organero, F. Ana, L. Fonseca, F. Peris, V. Brevia, O. Selva, A. Perello, C. Cabedo, V. Gonçalves, R. Ferreira, M. Marques Dias, F. Daassou, A. Barkaoui, K. Benkhaldoun, Z. Guennoun, M. Chouqar, J. Jehin, E. Rinner, C. Lloyd, J. El Moutamid, M. Lamarche, C. Pollock, J.T. Caton, D.B. Kouprianov, V. Timerson, B.W. Blanchard, G. Payet, B. Peyrot, A. Teng-Chuen-Yu, J.-P. Françoise, J. Mondon, B. Payet, T. Boissel, C. Castets, M. Hubbard, W.B. Hill, R. Reitsema, H.J. Mousis, O. Ball, L. Neilsen, G. Hutcheon, S. Lay, K. Anderson, P. Moy, M. Jonsen, M. Pink, I. Walters, R. Downs, B.
Abstract: Context. A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of which yielded a central flash detection. Aims. We aimed at constraining Triton's atmospheric structure and the seasonal variations of its atmospheric pressure since the Voyager 2 epoch (1989). We also derived the shape of the lower atmosphere from central flash analysis. Methods. We used Abel inversions and direct ray-tracing code to provide the density, pressure, and temperature profiles in the altitude range ∼8 km to ∼190 km, corresponding to pressure levels from 9 μbar down to a few nanobars. Results. (i) A pressure of 1.18 ± 0.03 μbar is found at a reference radius of 1400 km (47 km altitude). (ii) A new analysis of the Voyager 2 radio science occultation shows that this is consistent with an extrapolation of pressure down to the surface pressure obtained in 1989. (iii) A survey of occultations obtained between 1989 and 2017 suggests that an enhancement in surface pressure as reported during the 1990s might be real, but debatable, due to very few high S/N light curves and data accessible for reanalysis. The volatile transport model analysed supports a moderate increase in surface pressure, with a maximum value around 2005-2015 no higher than 23 μbar. The pressures observed in 1995-1997 and 2017 appear mutually inconsistent with the volatile transport model presented here. (iv) The central flash structure does not show evidence of an atmospheric distortion. We find an upper limit of 0.0011 for the apparent oblateness of the atmosphere near the 8 km altitude. ©
Published: 2022

25. Instrumental methods for professional and amateur collaborations in planetary astronomy

Author: Mousis, O., Hueso, R., Beaulieu, J.-P., Bouley, S., Carry, B., Colas, F., Klotz, A., Pellier, C., Petit, J.-M., Rousselot, P., Ali-Dib, M., Beisker, W., Birlan, M., Buil, C., Delsanti, A., Frappa, E., Hammel, H. B., Levasseur-Regourd, A. C., Orton, G. S., Sánchez-Lavega, A., Santerne, A., Tanga, P., Vaubaillon, J., Zanda, B., Baratoux, D., Böhm, T., Boudon, V., Bouquet, A., Buzzi, L., Dauvergne, J. -L., Decock, A., Delcroix, M., Drossart, P., Esseiva, N., Fischer, G., Fletcher, L. N., Foglia, S., M. Gómez-Forrellad, J., Guarro-Fló, J., Herald, D., Jehin, E., Kugel, F., Lebreton, J. -P., Lecacheux, J., Leroy, A., Maquet, L., Masi, G., Maury, A., Meyer, F., Pérez-Hoyos, S., Rajpurohit, A. S., Rinner, C., Rogers, J. H., Roques, F., Schmude, Jr., R.W., Sicardy, B., Tregon, B., Vanhuysse, M., Wesley, A., and Widemann, T.
Published: 2014
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26. 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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27. EChO: Exoplanet characterisation observatory

Author: Tinetti, G., Beaulieu, J. P., Henning, T., Meyer, M., Micela, G., Ribas, I., Stam, D., Swain, M., Krause, O., Ollivier, M., Pace, E., Swinyard, B., Aylward, A., van Boekel, R., Coradini, A., Encrenaz, T., Snellen, I., Zapatero-Osorio, M. R., Bouwman, J., Cho, J. Y-K., Coudé de Foresto, V., Guillot, T., Lopez-Morales, M., Mueller-Wodarg, I., Palle, E., Selsis, F., Sozzetti, A., Ade, P. A. R., Achilleos, N., Adriani, A., Agnor, C. B., Afonso, C., Prieto, C. Allende, Bakos, G., Barber, R. J., Barlow, M., Batista, V., Bernath, P., Bézard, B., Bordé, P., Brown, L. R., Cassan, A., Cavarroc, C., Ciaravella, A., Cockell, C., Coustenis, A., Danielski, C., Decin, L., Kok, R. De, Demangeon, O., Deroo, P., Doel, P., Drossart, P., Fletcher, L. N., Focardi, M., Forget, F., Fossey, S., Fouqué, P., Frith, J., Galand, M., Gaulme, P., Hernández, J. I. González, Grasset, O., Grassi, D., Grenfell, J. L., Griffin, M. J., Griffith, C. A., Grözinger, U., Guedel, M., Guio, P., Hainaut, O., Hargreaves, R., Hauschildt, P. H., Heng, K., Heyrovsky, D., Hueso, R., Irwin, P., Kaltenegger, L., Kervella, P., Kipping, D., Koskinen, T. T., Kovács, G., La Barbera, A., Lammer, H., Lellouch, E., Leto, G., Lopez Morales, M., Lopez Valverde, M. A., Lopez-Puertas, M., Lovis, C., Maggio, A., Maillard, J. P., Maldonado Prado, J., Marquette, J. B., Martin-Torres, F. J., Maxted, P., Miller, S., Molinari, S., Montes, D., Moro-Martin, A., Moses, J. I., Mousis, O., Nguyen Tuong, N., Nelson, R., Orton, G. S., Pantin, E., Pascale, E., Pezzuto, S., Pinfield, D., Poretti, E., Prinja, R., Prisinzano, L., Rees, J. M., Reiners, A., Samuel, B., Sánchez-Lavega, A., Forcada, J. Sanz, Sasselov, D., Savini, G., Sicardy, B., Smith, A., Stixrude, L., Strazzulla, G., Tennyson, J., Tessenyi, M., Vasisht, G., Vinatier, S., Viti, S., Waldmann, I., White, G. J., Widemann, T., Wordsworth, R., Yelle, R., Yung, Y., and Yurchenko, S. N.
Published: 2012
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28. Albedo and atmospheric constraints of dwarf planet Makemake from a stellar occultation

Author: Ortiz, J. L., Sicardy, B., Braga-Ribas, F., Alvarez-Candal, A., Lellouch, E., Duffard, R., Pinilla-Alonso, N., Ivanov, V. D., Littlefair, S. P., Camargo, J. I. B., Assafin, M., Unda-Sanzana, E., Jehin, E., Morales, N., Tancredi, G., Gil-Hutton, R., de la Cueva, I., Colque, J. P., Da Silva Neto, D. N., Manfroid, J., Thirouin, A., Gutiérrez, P. J., Lecacheux, J., Gillon, M., Maury, A., Colas, F., Licandro, J., Mueller, T., Jacques, C., Weaver, D., Milone, A., Salvo, R., Bruzzone, S., Organero, F., Behrend, R., Roland, S., Vieira-Martins, R., Widemann, T., Roques, F., Santos-Sanz, P., Hestroffer, D., Dhillon, V. S., Marsh, T. R., Harlingten, C., Bagatin, Campo A., Alonso, M. L., Ortiz, M., Colazo, C., Lima, H. J. F., Oliveira, A. S., Kerber, L. O., Smiljanic, R., Pimentel, E., Giacchini, B., Cacella, P., and Emilio, M.
Published: 2012
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29. A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation

Author: Sicardy, B., Ortiz, J. L., Assafin, M., Jehin, E., Maury, A., Lellouch, E., Hutton, Gil R., Braga-Ribas, F., Colas, F., Hestroffer, D., Lecacheux, J., Roques, F., Santos-Sanz, P., Widemann, T., Morales, N., Duffard, R., Thirouin, A., Castro-Tirado, A. J., Jelínek, M., Kubánek, P., Sota, A., Sánchez-Ramírez, R., Andrei, A. H., Camargo, J. I. B., da Silva Neto, D. N., Gomes, Ramos A., Martins, Vieira R., Gillon, M., Manfroid, J., Tozzi, G. P., Harlingten, C., Saravia, S., Behrend, R., Mottola, S., Melendo, García E., Peris, V., Fabregat, J., Madiedo, J. M., Cuesta, L., Eibe, M. T., Ullán, A., Organero, F., Pastor, S., de los Reyes, J. A., Pedraz, S., Castro, A., de la Cueva, I., Muler, G., Steele, I. A., Cebrián, M., Montañés-Rodríguez, P., Oscoz, A., Weaver, D., Jacques, C., Corradi, W. J. B., Santos, F. P., Reis, W., Milone, A., Emilio, M., Gutiérrez, L., Vázquez, R., and Hernández-Toledo, H.
Published: 2011
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30. A stringent upper limit of the PH3abundance at the cloud top of Venus

Author: Encrenaz, T., primary, Greathouse, T. K., additional, Marcq, E., additional, Widemann, T., additional, Bézard, B., additional, Fouchet, T., additional, Giles, R., additional, Sagawa, H., additional, Greaves, J., additional, and Sousa-Silva, C., additional
Published: 2020
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31. HDO and SO2thermal mapping on Venus

Author: Encrenaz, T., primary, Greathouse, T. K., additional, Marcq, E., additional, Sagawa, H., additional, Widemann, T., additional, Bézard, B., additional, Fouchet, T., additional, Lefèvre, F., additional, Lebonnois, S., additional, Atreya, S. K., additional, Lee, Y. J., additional, Giles, R., additional, Watanabe, S., additional, Shao, W., additional, Zhang, X., additional, and Bierson, C. J., additional
Published: 2020
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32. Overview of useful spectral regions for Venus: An update to encourage observations complementary to the Akatsuki mission

Author: Peralta, J., Lee, Y. J., McGouldrick, K., Sanchez-Lavega, A., Widemann, T., Sagawa, Hideo, Imamura, Takeshi, Nakamura, Masato, Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Center for Mathematical Sciences, The University of Aizu, Departamento de Fı'sica Aplicada I, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency [Sagamihara] (JAXA), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], 010504 meteorology & atmospheric sciences, biology, Computer science, Venus, Astronomy and Astrophysics, biology.organism_classification, 01 natural sciences, Astrobiology, law.invention, Orbiter, Planet, law, Space and Planetary Science, 0103 physical sciences, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010303 astronomy & astrophysics, Amateur, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Remote sensing
Abstract: Accepted: 2017-01-26, 資料番号: SA1160342000
Published: 2017

33. Preparing EnVision: SO2 measurements below and above Venus' clouds

Author: Marcq, Emmanuel, Jessup, K. L., Encrenaz, Thérèse, Baggio, Lucio, Amine, Ismaïl, Duquesnoy, Marc, Montmessin, Franck, Lefèvre, Franck, Bertaux, Jean-Loup, Vandaele, A. C., Robert, S., Helbert, J., Widemann, T., Wilson, C., Ghail, R., IMPEC - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Southwest Research Institute [Boulder] (SwRI), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), University of Oxford [Oxford], Royal Holloway [University of London] (RHUL), PLANETO - LATMOS, Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDU]Sciences of the Universe [physics]
Abstract: International audience; One of the primary objectives of the preselected En-Vision M5 proposal is the monitoring of volcanogenicspecies in Venus’ atmosphere, one of the most promi-nent being sulphur dioxide (SO2). Monitoring SO2below the clouds can be performed on the night-side near2.4μm, and is one science objective of theVenSpec-H channel (P.I.: A. C. Vandaele, BIRA) on-board EnVision. Monitoring SO2above the cloudscan be performed on the dayside in the200-300 nmrange, and is the main science objective of theVenSpec-U channel (P.I.: E. Marcq, LATMOS). Herewe present the analysis of two analogous datasets,namely IRTF/iSHELL ground based observations onthe nightside of Venus, and the most recent reanalay-sis of the Venus Express/SPICAV-UV dataset on thedayside of Venus
Published: 2019

34. Pluto's lower atmosphere and pressure evolution from ground-based stellar occultations, 1988-2016

Author: Meza, E, Sicardy, B, Assafin, M, Ortiz, JL, Bertrand, T, Lellouch, E, Desmars, J, Forget, F, Bérard, D, Doressoundiram, A, Lecacheux, J, Oliveira, JM, Roques, F, Widemann, T, Colas, F, Vachier, F, Renner, S, Leiva, R, Braga-Ribas, F, Benedetti-Rossi, G, Camargo, JIB, Dias-Oliveira, A, Morgado, B, Gomes-Júnior, AR, Vieira-Martins, R, Behrend, R, Tirado, AC, Duffard, R, Morales, N, Santos-Sanz, P, Jelínek, M, Cunniffe, R, Querel, R, Harnisch, M, Jansen, R, Pennell, A, Todd, S, Ivanov, VD, Opitom, C, Gillon, M, Jehin, E, Manfroid, J, Pollock, J, Reichart, DE, Haislip, JB, Ivarsen, KM, LaCluyze, AP, Maury, A, Gil-Hutton, R, Dhillon, V, Littlefair, S, Marsh, T, Veillet, C, Bath, K-L, Beisker, W, Bode, H-J, Kretlow, M, Herald, D, Gault, D, Kerr, S, Pavlov, H, Faragó, O, Klös, O, Frappa, E, Lavayssière, M, Cole, AA, Giles, AB, Greenhill, JG, Hill, KM, Buie, MW, Olkin, CB, Young, EF, Young, LA, Wasserman, LH, Devogèle, M, French, RG, Bianco, FB, Marchis, F, Brosch, N, Kaspi, S, Polishook, D, Manulis, I, Larbi, MAM, Benkhaldoun, Z, Daassou, A, Azhari, YE, Moulane, Y, Broughton, J, Milner, J, Dobosz, T, Bolt, G, Lade, B, Gilmore, A, Kilmartin, P, Allen, WH, Graham, PB, Loader, B, McKay, G, Talbot, J, Parker, S, Abe, L, Bendjoya, P, Rivet, J-P, Vernet, D, Fabrizio, LD, Lorenzi, V, Magazzù, A, Molinari, E, Gazeas, K, Tzouganatos, L, Carbognani, A, Bonnoli, G, Marchini, A, Leto, G, Sanchez, RZ, Mancini, L, Kattentidt, B, Dohrmann, M, Guhl, K, Rothe, W, Walzel, K, Wortmann, G, Eberle, A, Hampf, D, Ohlert, J, Krannich, G, Murawsky, G, Gährken, B, Gloistein, D, Alonso, S, Román, A, Communal, J-E, Jabet, F, Visscher, SD, Sérot, J, Janik, T, Moravec, Z, Machado, P, Selva, A, Perelló, C, Rovira, J, Conti, M, Papini, R, Salvaggio, F, Noschese, A, Tsamis, V, Tigani, K, Barroy, P, Irzyk, M, Neel, D, Godard, JP, Lanoiselée, D, Sogorb, P, Vérilhac, D, Bretton, M, Signoret, F, Ciabattari, F, Naves, R, Boutet, M, Queiroz, JD, Lindner, P, Lindner, K, Enskonatus, P, Dangl, G, Tordai, T, Eichler, H, Hattenbach, J, Peterson, C, Molnar, LA, and Howell, RR
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), FOS: Physical sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. Pluto's tenuous nitrogen (N2) atmosphere undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has been recently (July 2015) observed by the New Horizons spacecraft. Goals are (i) construct a well calibrated record of the seasonal evolution of surface pressure on Pluto and (ii) constrain the structure of the lower atmosphere using a central flash observed in 2015. Method: eleven stellar occultations by Pluto observed between 2002 and 2016 are used to retrieve atmospheric profiles (density, pressure, temperature) between $\sim$5 km and $\sim$380 km altitude levels (i.e. pressures from about 10 microbar to 10 nanobar). Results: (i) Pressure has suffered a monotonic increase from 1988 to 2016, that is compared to a seasonal volatile transport model, from which tight constraints on a combination of albedo and emissivity of N2 ice are derived; (ii) A central flash observed on 2015 June 29 is consistent with New Horizons REX profiles, provided that (a) large diurnal temperature variations (not expected by current models) occur over Sputnik Planitia and/or (b) hazes with tangential optical depth of about 0.3 are present at 4-7 km altitude levels and/or (c) the nominal REX density values are overestimated by an implausibly large factor of about 20% and/or (d) higher terrains block part of the flash in the Charon facing hemisphere., 21 pages, 11 figures
Published: 2019

35. The Venus Emissivity Mapper - Obtaining Global Mineralogy of Venus from Orbit on the ESA EnVision and NASA VERITAS Missions to Venus

Author: Helbert, Jörn, Dyar, M. D., Walter, Ingo, Rosas-Ortiz, Y.M., Widemann, T., Marcq, E., Guignan, Gabriel, Maturilli, Alessandro, Varatharajan, Indhu, Ferrari, Sabrina, Mueller, Nils, Kappel, David, D'Amore, Mario, Boerner, A., Tsang, C., Arnold, Gabriele, Smrekar, S., and Ghail, Richard
Subjects: Leitungsbereich PF, Emissivity, EnVision, Global, VERITAS, Mineralogy, NASA, Venus, Mapper, Missions, Institut für Optische Sensorsysteme
Published: 2019

36. Lower atmosphere and pressure evolution on Pluto from ground-based stellar occultations, 1988-2016

Author: Meza, E. Sicardy, B. Assafin, M. Ortiz, J.L. Bertrand, T. Lellouch, E. Desmars, J. Forget, F. Bérard, D. Doressoundiram, A. Lecacheux, J. Marques Oliveira, J. Roques, F. Widemann, T. Colas, F. Vachier, F. Renner, S. Leiva, R. Braga-Ribas, F. Benedetti-Rossi, G. Camargo, J.I.B. Dias-Oliveira, A. Morgado, B. Gomes-Júnior, A.R. Vieira-Martins, R. Behrend, R. Castro Tirado, A. Duffard, R. Morales, N. Santos-Sanz, P. Jelínek, M. Cunniffe, R. Querel, R. Harnisch, M. Jansen, R. Pennell, A. Todd, S. Ivanov, V.D. Opitom, C. Gillon, M. Jehin, E. Manfroid, J. Pollock, J. Reichart, D.E. Haislip, J.B. Ivarsen, K.M. LaCluyze, A.P. Maury, A. Gil-Hutton, R. Dhillon, V. Littlefair, S. Marsh, T. Veillet, C. Bath, K.-L. Beisker, W. Bode, H.-J. Kretlow, M. Herald, D. Gault, D. Kerr, S. Pavlov, H. Faragó, O. Klös, O. Frappa, E. Lavayssière, M. Cole, A.A. Giles, A.B. Greenhill, J.G. Hill, K.M. Buie, M.W. Olkin, C.B. Young, E.F. Young, L.A. Wasserman, L.H. Devogèle, M. French, R.G. Bianco, F.B. Marchis, F. Brosch, N. Kaspi, S. Polishook, D. Manulis, I. Ait Moulay Larbi, M. Benkhaldoun, Z. Daassou, A. El Azhari, Y. Moulane, Y. Broughton, J. Milner, J. Dobosz, T. Bolt, G. Lade, B. Gilmore, A. Kilmartin, P. Allen, W.H. Graham, P.B. Loader, B. McKay, G. Talbot, J. Parker, S. Abe, L. Bendjoya, P. Rivet, J.-P. Vernet, D. Di Fabrizio, L. Lorenzi, V. Magazzú, A. Molinari, E. Gazeas, K. Tzouganatos, L. Carbognani, A. Bonnoli, G. Marchini, A. Leto, G. Zanmar Sanchez, R. Mancini, L. Kattentidt, B. Dohrmann, M. Guhl, K. Rothe, W. Walzel, K. Wortmann, G. Eberle, A. Hampf, D. Ohlert, J. Krannich, G. Murawsky, G. Gährken, B. Gloistein, D. Alonso, S. Román, A. Communal, J.-E. Jabet, F. DeVisscher, S. Sérot, J. Janik, T. Moravec, Z. MacHado, P. Selva, A. Perelló, C. Rovira, J. Conti, M. Papini, R. Salvaggio, F. Noschese, A. Tsamis, V. Tigani, K. Barroy, P. Irzyk, M. Neel, D. Godard, J.P. Lanoiselée, D. Sogorb, P. Vérilhac, D. Bretton, M. Signoret, F. Ciabattari, F. Naves, R. Boutet, M. De Queiroz, J. Lindner, P. Lindner, K. Enskonatus, P. Dangl, G. Tordai, T. Eichler, H. Hattenbach, J. Peterson, C. Molnar, L.A. Howell, R.R.
Abstract: Context. The tenuous nitrogen (N2) atmosphere on Pluto undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has recently (July 2015) been observed by the New Horizons spacecraft. Aims. The main goals of this study are (i) to construct a well calibrated record of the seasonal evolution of surface pressure on Pluto and (ii) to constrain the structure of the lower atmosphere using a central flash observed in 2015. Methods. Eleven stellar occultations by Pluto observed between 2002 and 2016 are used to retrieve atmospheric profiles (density, pressure, temperature) between altitude levels of ∼5 and ∼380 km (i.e. pressures from ∼10 μbar to 10 nbar). Results. (i) Pressure has suffered a monotonic increase from 1988 to 2016, that is compared to a seasonal volatile transport model, from which tight constraints on a combination of albedo and emissivity of N2 ice are derived. (ii) A central flash observed on 2015 June 29 is consistent with New Horizons REX profiles, provided that (a) large diurnal temperature variations (not expected by current models) occur over Sputnik Planitia; and/or (b) hazes with tangential optical depth of ∼0.3 are present at 4-7 km altitude levels; and/or (c) the nominal REX density values are overestimated by an implausibly large factor of ∼20%; and/or (d) higher terrains block part of the flash in the Charon facing hemisphere. © E. Meza et al. 2019.
Published: 2019

37. Charon's size and an upper limit on its atmosphere from a stellar occultation

Author: Sicardy, B., Bellucci, A., Gendron, E., Lacombe, F., Lacour, S., Lecacheux, J., Lellouch, E., Renner, S., Pau, S., Roques, F., Widemann, T., Colas, F., Vachier, F., Vieira Martins, R., Ageorges, N., Hainaut, O., Marco, O., Beisker, W., Hummel, E., Feinstein, C., Levato, H., Maury, A., Frappa, E., Gaillard, B., Lavayssière, M., Di Sora, M., Mallia, F., Masi, G., Behrend, R., Carrier, F., Mousis, O., Rousselot, P., Alvarez-Candal, A., Lazzaro, D., Veiga, C., Andrei, A. H., Assafin, M., da Silva Neto, D. N., Jacques, C., Pimentel, E., Weaver, D., Lecampion, J.-F., Doncel, F., Momiyama, T., and Tancredi, G.
Published: 2006

38. The VenSpec suite on the ESA EnVision mission to Venus

Author: Helbert, J., Vandaele, Ann Carine, Marcq, E., Robert, S., Ryan, C., Guignan, G., Rosas-Ortiz, Y., Neefs, E., Thomas, Ian R., Arnold, G., Peter, G., Widemann, T., Lara, Luisa María, Helbert, J., Vandaele, Ann Carine, Marcq, E., Robert, S., Ryan, C., Guignan, G., Rosas-Ortiz, Y., Neefs, E., Thomas, Ian R., Arnold, G., Peter, G., Widemann, T., and Lara, Luisa María
Abstract: The VenSpec instrument suite is part of the payload for the ESA M5 mission proposal EnVision which is currently in a competitive Phase A study. VenSpec consists of three channels: VenSpec-M, VenSpec-H and VenSpec-U. VenSpec-M will provide near-global compositional data on rock types, weathering, and crustal evolution by mapping the Venus surface in five atmospheric windows. VenSpec-H will be dedicated to extremely high-resolution atmospheric measurements. The main objective of the VenSpec-H instrument is to detect and quantify SO2, H2O and HDO in the lower atmosphere, to enable characterization of volcanic plumes and other sources of gas exchange with the surface of Venus, complementing VenSAR and VenSpecM surface and SRS subsurface observations. VenSpec-U will monitor sulphured minor species (mainly SO and SO2) and the as yet unknown UV absorber in Venusian upper clouds and just above. In combination, VenSpec will provide unprecedented insights into the current state of Venus and its past evolution. VenSpec will perform a comprehensive search for volcanic activity by targeting atmospheric signatures, thermal signatures and compositional signatures, as well as a global map of surface composition. © COPYRIGHT SPIE.
Published: 2019

39. Large changes in Plutoʼs atmosphere as revealed by recent stellar occultations

Author: Sicardy, B., Widemann, T., Lellouch, E., Veillet, C., Cuillandre, J.-C., Colas, F., Roques, F., Beisker, W., Kretlow, M., Lagrange, A.-M., Gendron, E., Lacombe, F., Lecacheux, J., Birnbaum, C., Fienga, A., Leyrat, C., Maury, A., Raynaud, E., Renner, S., Schultheis, M., Brooks, K., Delsanti, A., Hainaut, O. R., Gilmozzi, R., Lidman, C., Spyromilio, J., Rapaport, M., Rosenzweig, P., Naranjo, O., Porras, L., Díaz, F., Calderón, H., Carrillo, S., Carvajal, A., Recalde, E., Cavero, Gaviria L., Montalvo, C., Barría, D., Campos, R., Duffard, R., and Levato, H.
Published: 2003

40. The Venus Emissivity Mapper - Investigating the Atmospheric Structure and Dynamics of Venus' Polar Region

Author: Widemann, T., Marcq, E., Tsang, C. C. C., Müller, Nils, Kappel, David, Helbert, Jörn, and Dyar, M. D.
Subjects: Asteroiden und Kometen, remote sensing, spectroscopy, Leitungsbereich PF, Venus
Abstract: The Venus Emissivity Mapper (VEM) is the first flight instrument specially designed to map the surface of Venus using the narrow atmospheric windows around 1 micron. VEM is proposed for the European Space Agency's M5/EnVision proposal in combination with a high-resolution radar mapper (see Abstract #1937). Mapping of Venus with VEx/VIRTIS using the 1.02 micron thermal emission band can be viewed as a proof-of-concept for an orbital remote sensing approach to surface composition and weathering studies for Venus. Thermal brightness on Venus' night side is mainly modulated by the lower clouds, imaged at 2.3 micron by the Akatsuki IR2 camera. Thanks to the circular polar orbit geometry of M5/EnVision, VEM has the unique capability to (1) better constrain the microphysics of the lower cloud particles in three spectral bands at 1.195, 1.310 and 1.510 micron at a spatial resolution of ~10 km, and (2) investigate short-timescale cloud dynamics and thus local wind speeds by tracking cloud features in both polar regions.
Published: 2018

41. Lower atmosphere and pressure evolution on Pluto from ground-based stellar occultations, 1988–2016

Author: Meza, E., primary, Sicardy, B., additional, Assafin, M., additional, Ortiz, J. L., additional, Bertrand, T., additional, Lellouch, E., additional, Desmars, J., additional, Forget, F., additional, Bérard, D., additional, Doressoundiram, A., additional, Lecacheux, J., additional, Oliveira, J. Marques, additional, Roques, F., additional, Widemann, T., additional, Colas, F., additional, Vachier, F., additional, Renner, S., additional, Leiva, R., additional, Braga-Ribas, F., additional, Benedetti-Rossi, G., additional, Camargo, J. I. B., additional, Dias-Oliveira, A., additional, Morgado, B., additional, Gomes-Júnior, A. R., additional, Vieira-Martins, R., additional, Behrend, R., additional, Tirado, A. Castro, additional, Duffard, R., additional, Morales, N., additional, Santos-Sanz, P., additional, Jelínek, M., additional, Cunniffe, R., additional, Querel, R., additional, Harnisch, M., additional, Jansen, R., additional, Pennell, A., additional, Todd, S., additional, Ivanov, V. D., additional, Opitom, C., additional, Gillon, M., additional, Jehin, E., additional, Manfroid, J., additional, Pollock, J., additional, Reichart, D. E., additional, Haislip, J. B., additional, Ivarsen, K. M., additional, LaCluyze, A. P., additional, Maury, A., additional, Gil-Hutton, R., additional, Dhillon, V., additional, Littlefair, S., additional, Marsh, T., additional, Veillet, C., additional, Bath, K.-L., additional, Beisker, W., additional, Bode, H.-J., additional, Kretlow, M., additional, Herald, D., additional, Gault, D., additional, Kerr, S., additional, Pavlov, H., additional, Faragó, O., additional, Klös, O., additional, Frappa, E., additional, Lavayssière, M., additional, Cole, A. A., additional, Giles, A. B., additional, Greenhill, J. G., additional, Hill, K. M., additional, Buie, M. W., additional, Olkin, C. B., additional, Young, E. F., additional, Young, L. A., additional, Wasserman, L. H., additional, Devogèle, M., additional, French, R. G., additional, Bianco, F. B., additional, Marchis, F., additional, Brosch, N., additional, Kaspi, S., additional, Polishook, D., additional, Manulis, I., additional, Ait Moulay Larbi, M., additional, Benkhaldoun, Z., additional, Daassou, A., additional, El Azhari, Y., additional, Moulane, Y., additional, Broughton, J., additional, Milner, J., additional, Dobosz, T., additional, Bolt, G., additional, Lade, B., additional, Gilmore, A., additional, Kilmartin, P., additional, Allen, W. H., additional, Graham, P. B., additional, Loader, B., additional, McKay, G., additional, Talbot, J., additional, Parker, S., additional, Abe, L., additional, Bendjoya, Ph., additional, Rivet, J.-P., additional, Vernet, D., additional, Di Fabrizio, L., additional, Lorenzi, V., additional, Magazzú, A., additional, Molinari, E., additional, Gazeas, K., additional, Tzouganatos, L., additional, Carbognani, A., additional, Bonnoli, G., additional, Marchini, A., additional, Leto, G., additional, Sanchez, R. Zanmar, additional, Mancini, L., additional, Kattentidt, B., additional, Dohrmann, M., additional, Guhl, K., additional, Rothe, W., additional, Walzel, K., additional, Wortmann, G., additional, Eberle, A., additional, Hampf, D., additional, Ohlert, J., additional, Krannich, G., additional, Murawsky, G., additional, Gährken, B., additional, Gloistein, D., additional, Alonso, S., additional, Román, A., additional, Communal, J.-E., additional, Jabet, F., additional, deVisscher, S., additional, Sérot, J., additional, Janik, T., additional, Moravec, Z., additional, Machado, P., additional, Selva, A., additional, Perelló, C., additional, Rovira, J., additional, Conti, M., additional, Papini, R., additional, Salvaggio, F., additional, Noschese, A., additional, Tsamis, V., additional, Tigani, K., additional, Barroy, P., additional, Irzyk, M., additional, Neel, D., additional, Godard, J. P., additional, Lanoiselée, D., additional, Sogorb, P., additional, Vérilhac, D., additional, Bretton, M., additional, Signoret, F., additional, Ciabattari, F., additional, Naves, R., additional, Boutet, M., additional, De Queiroz, J., additional, Lindner, P., additional, Lindner, K., additional, Enskonatus, P., additional, Dangl, G., additional, Tordai, T., additional, Eichler, H., additional, Hattenbach, J., additional, Peterson, C., additional, Molnar, L. A., additional, and Howell, R. R., additional
Published: 2019
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42. HDO and SO2 thermal mapping on Venus

Author: Encrenaz, T., primary, Greathouse, T. K., additional, Marcq, E., additional, Sagawa, H., additional, Widemann, T., additional, Bézard, B., additional, Fouchet, T., additional, Lefèvre, F., additional, Lebonnois, S., additional, Atreya, S. K., additional, Lee, Y. J., additional, Giles, R., additional, and Watanabe, S., additional
Published: 2019
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43. The Venus Emissivity Mapper - Investigating the Atmospheric Structure and Dynamics of Venus' Polar Region

Author: Widemann, T., Marcq, E., Tsang, C. C. C., Müller, N., Kappel, David, Helbert, Jörn, Dyar, M. D., and Smrekar, S.E.
Subjects: remote sensing, spectroscopy, Venus Atmosphere Winds Venus Emissivity Mapper, Venus
Published: 2017

44. The Venus Emissivity Mapper - gaining a global perspective on the surface composition of Venus

Author: Helbert, Jörn, Dyar, M. D., Widemann, T., Marcq, E., Maturilli, Alessandro, Müller, N., Kappel, David, Ferrari, Sabrina, D'Amore, M., Tsang, C. C. C., and Smrekar, S.E.
Subjects: Venus mineralogy venus emissivity mapper comparative planetology
Published: 2017

45. Probing Rock Type, Fe Redox State, and Transition Metal Contents with Six-Window VNIR Spectroscopy Under Venus Conditions

Author: Dyar, M. D., Jorn Helbert, Boucher, T., Wendler, D., Walter, I., Widemann, T., Marcq, E., Maturilli, A., Ferrari, S., D Amore, M., Mueller, N., and Smrekar, S.
Subjects: Hochgeschwindigkeitselektronik, Leitungsbereich PF, Planetare Sensorsysteme, Venus Mineralogy Laboratory
Abstract: VEM-window data are shown to distinguish among key rock types on Venus, and evaluate redox state and transition metal contents of Venus surface rocks.
Published: 2017

46. SO2 Vapor Equilibrium with Oxidized Surface Rocks

Author: Widemann, T., Head, J.W., Helbert, Jörn, and Smrekar, S.E.
Subjects: Venus Weathering mineralogy
Published: 2017

47. The Venus Emissivity Mapper (VEM) Prototype

Author: Wendler, Dennis, Helbert, Jörn, Walter, Ingo, Widemann, T., Guignan, Gabriel, Marcq, E., Maturilli, Alessandro, Ferrari, Sabrina, D'Amore, M., Müller, N., Dyar, M. D., and Smrekar, S.E.
Subjects: Hochgeschwindigkeitselektronik, Leitungsbereich PF, Venus Emissivity Mapper Prototype calibration, Planetare Sensorsysteme
Published: 2017

48. A stringent upper limit of the PH3 abundance at the cloud top of Venus.

Author: Encrenaz, T., Greathouse, T. K., Marcq, E., Widemann, T., Bézard, B., Fouchet, T., Giles, R., Sagawa, H., Greaves, J., and Sousa-Silva, C.
Subjects: MESOSPHERE, SPECTRAL imaging, PLANETARY atmospheres, PLANETARY systems, NATURAL satellite atmospheres
Abstract: Aims. Following the announcement of the detection of phosphine (PH3) in the cloud deck of Venus at millimeter wavelengths, we searched for other possible signatures of this molecule in the infrared range. Methods. Since 2012, we have been observing Venus in the thermal infrared at various wavelengths to monitor the behavior of SO2 and H2O at the cloud top. We identified a spectral interval recorded in March 2015 around 950 cm−1 where a PH3 transition is present. Results. From the absence of any feature at this frequency, we derive, on the disk-integrated spectrum, a 3-σ upper limit of 5 ppbv for the PH3 mixing ratio, which is assumed to be constant throughout the atmosphere. This limit is four times lower than the disk-integrated mixing ratio derived at millimeter wavelengths. Conclusions. Our result places a strong constraint on the maximum PH3 abundance at the cloud top and in the lower mesosphere of Venus. [ABSTRACT FROM AUTHOR]
Published: 2020
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49. The Venus Emissivity Mapper

Author: Helbert, Jörn, Marcq, E., Widemann, T., Müller, N., Kappel, David, Tsang, C. C. C., Maturilli, Alessandro, Ferrari, Sabrina, D'Amore, Mario, Dyar, M. Darby, and Smrekar, S.E.
Subjects: Surface, VEM, Institut für Planetenforschung, Leitungsbereich PF, Emissivity, VERITAS, Venus
Abstract: The permanent cloud cover of Venus prohibits observations of the surface with traditional imaging techniques over the entire visible spectral range. Fortunately, Venus' atmospheric gases are largely transparent in narrow spectral windows near 1 mm. Ground observers were the first to successfully use these windows, followed by spacecraft observations during the flyby of the Galileo mission on its way to Jupiter and most recently from Venus orbit by ESA's Venus Express with the VMC and VIRTIS instruments. Analyses of VIRTIS measurements have successfully demonstrated that surface information can be extracted from these windows, but the design of the instrument limited its use for more in-depth surface investigations.Based on experience gained from using VIRTIS to observe the surface of Venus and new high temperature laboratory experiments currently performed at the Planetary Spectroscopy Laboratory of DLR, we have designed the multi-spectral Venus Emissivity Mapper (VEM). Observations from VIRTIS have revealed surface emissivity variations correlated with geological features, but existing data sets contain only three spectral channels. VEM is optimized to map the surface composition and texture, and to search for active volcanism using the narrow atmospheric windows, building on lessons from prior instrumentation and methodology. It offers an opportunity to gain important information about surface mineralogy and texture by virtue of having six different channels for surface mapping.VEM is focused mainly on observing the surface, mapping in all near-IR atmospheric windows using filters with spectral characteristics optimized for the wavelengths and widths of those windows. It also observes bands necessary for correcting atmospheric effects; these bands also provide valuable scientific data on composition as well as altitude and size distribution of the cloud particles, and on H2O vapor abundance variations in the lowest 15 km of the atmosphere.In combination with a high-resolution radar mapper that provides accurate topographic data as planned for the NASA VERITAS mission or for the ESA EnVision mission, VEM will provide new insights into current properties and the geologic evolution of Venus.
Published: 2016

50. Atmosperic Science with VEM on board Veritas

Author: Marcq, E., Müller, N., Tsang, C. C. C., Kappel, David, Widemann, T., Helbert, Jörn, and Smrekar, S.E.
Subjects: VEM, Atmosphere, Institut für Planetenforschung, Clouds, Leitungsbereich PF, VERITAS, Venus
Abstract: Thermal brightness on Venus' night side is mainly modulated by the lower cloud layer extending from about 45 to 60 km in altitude, the most recent observations being the outstanding 2.3 µm images recorded by the IR2 camera onboard Akatsuki [Gibney, 2016]. The VEM multispectral imager (P.I.: J. Helbert, DLR) onboard the proposed NASA VERITAS orbiter (P.I.: S. Smrekar, JPL) has the capability to observe these lower clouds. The VEM filter bands at 1.195, 1.310 and 1.510 µm will acquire very accurate images of the clouds: resolution in Phase II orbit after spatial binning will be about 20 km, which is close to the atmospheric blurring limit. This will lead to the acquisition of a large data set that allows for the study of the lower cloud morphology and climatology with good coverage in latitude, planetocentric longitude and local solar time. On the other hand, variations in the ratios of these three bands would help in constraining changes in composition, altitude and/or size distribution of the lower cloud particles [Barstow et al., 2012; Haus et al., 2014, 2015]. Such observations at small horizontal scales would be of great importance to microphysical models of Venus' clouds and haze system [McGouldrick et al., 2007]. Previous (Venus Express) or present (Akatsuki) observations of the lower clouds have proven the validity of these methods, but VEM onboard VERITAS will give an unprecedented coverage of the lower cloud horizontal structure on scales between 20 and 200 km in terms of spatial and temporal sampling, wavelength stability and signal-to-noise ratio. Tracking lower cloud motions as a proxy for wind measurements at a high spatial resolution would also be of great interest to mesoscale and general circulation models. Such a study is made challenging due to the fast zonal super-rotation so that clouds that are visible in the field of view usually cannot be observed 90 min later when VERITAS flies over the same region in its next orbit. However, the super-rotation breaks down for latitudes higher than 80°, so that cloud tracking would be possible in both north and south polar dipoles [Piccioni et al., 2007] well known for their complex and ever-changing dynamics.
Published: 2016

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