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MaGiV-1 is a candidate triple ellipsoidal star system in Vulpecula at coordinates RA(J2000) 19:52:19.13 DEC(J2000) +23:29:59.7 classified as ELL+ELL, number 2344411 in AAVSO VSX database. Through photometry from the TESS Space Telescope, two significant periods describing the orbital times of the components were identified using the Fourier transform. The analysis led to determining P(A-BC) = 4.269d the orbital period of A-BC pair, the primary component with the secondary component described by another pair, and P(BC) = 0.610d the orbital period of B-C pair, the inner ellipsoidal system. However, it cannot be completely ruled out that the shorter period can be explained by pulsations of one of the two components (e.g. by the GDOR type).

Muchos estudios sobre criminalidad han confundido medios con fines. El delito, como la democracia, son medios. Y los medios no son ni buenos ni malos: son efectivos o no. La legalidad, como modelo de vida, perdió legitimidad, veracidad y efectividad. El avance del delito está estrechamente relacionado esto. Este capítulo explica la importancia de discutir en torno al concepto de vidas que valgan la pena y revisar el alcance de la legalidad en la región. info:eu-repo/semantics/publishedVersion

La perversidad del discurso contra la corrupción, y no la corrupción como problema, brinda indicios de la degradación ética a la que se ha llegado. No se trata de defender la corrupción o de negarla como problema, sino de subrayar cómo la comprensión del flagelo es manipulada por presupuestos ideológicos, morales y jurídicos. Los hechos empíricos son significados de maneras incluso opuestas, dependiendo del interés particular de quien establece las significaciones. Y para el discurso anticorrupción, el régimen político es óptimo, el problema es que hay corrupción. Si eliminamos el flagelo, viviremos felices y en armonía. Administración sí, política no. info:eu-repo/semantics/publishedVersion

We characterise the origin and evolution of a mesoscale wave pattern in Jupiter's North Equatorial Belt (NEB), detected for the first time at 5 $��$m using a 2016-17 campaign of `lucky imaging' from the VISIR instrument on the Very Large Telescope and the NIRI instrument on the Gemini observatory, coupled with M-band imaging from Juno's JIRAM instrument during the first seven Juno orbits. The wave is compact, with a $1.1-1.4^\circ$ longitude wavelength (wavelength 1,300-1,600 km, wavenumber 260-330) that is stable over time, with wave crests aligned largely north-south between $14$ and $17^\circ$N (planetographic). The waves were initially identified in small ($10^\circ$ longitude) packets immediately west of cyclones in the NEB at $16^\circ$N, but extended to span wider longitude ranges over time. The waves exhibit a 7-10 K brightness temperature amplitude on top of a $\sim210$-K background at 5 $��$m. The thermal structure of the NEB allows for both inertio-gravity waves and gravity waves. Despite detection at 5 $��$m, this does not necessarily imply a deep location for the waves, and an upper tropospheric aerosol layer near 400-800 mbar could feature a gravity wave pattern modulating the visible-light reflectivity and attenuating the 5-$��$m radiance originating from deeper levels. Strong rifting activity appears to obliterate the pattern, which can change on timescales of weeks. The NEB underwent a new expansion and contraction episode in 2016-17 with associated cyclone-anticyclone formation, which could explain why the mesoscale wave pattern was more vivid in 2017 than ever before., 17 pages, 9 figures, published in Astronomical Journal

During the first perijove passage of the Juno mission, the Jovian InfraRed Auroral Mapper (JIRAM) observed a line of closely spaced oval features in Jupiter's southern hemisphere, between 30°S and 45°S. In this work, we focused on the longitudinal region covering the three ovals having higher contrast at 5 μm, i.e., between 120°W and 60°W in System III coordinates. We used the JIRAM's full spectral capability in the range 2.4-3 μm together with a Bayesian data inversion approach to retrieve maps of column densities and altitudes for an NH3 cloud and an N2H4 haze. The deep (under the saturation level) volume mixing ratio and the relative humidity for gaseous ammonia were also retrieved. Our results suggest different vortex activity for the three ovals. Updraft and downdraft together with considerations about the ammonia condensation could explain our maps providing evidences of cyclonic and anticyclonic structures.

The electromagnetic radiation emitted by the Jovian aurora extends from the X-Rays presumably caused by heavy ion precipitation and electron bremsstrahlung to thermal infrared radiation resulting from enhanced heating by high-energy charged particles. Many observations have been made since the 1990s with the Hubble Space Telescope, which was able to image the H2 Lyman and Werner bands that are directly excited by collisions of auroral electrons with H2. Ground-based telescopes obtained spectra and images of the thermal H3+ emission produced by charge transfer between H2+ and H+ ions and neutral H2 molecules in the lower thermosphere. However, so far the geometry of the observations limited the coverage from Earth orbit and only one case of simultaneous UV and infrared emissions has been described in the literature. The Juno mission provides the unique advantage to observe both Jovian hemispheres simultaneously in the two wavelength regions simultaneously and offers a more global coverage with unprecedented spatial resolution. This was the case....

The Jovian Infrared Auroral Mapper (JIRAM) is an imager/spectrometer on board NASA/Juno mission for the study of the Jovian aurorae. The first results of JIRAM's imager channel observations of the H3+ infrared emission, collected around the first Juno perijove, provide excellent spatial and temporal distribution of the Jovian aurorae, and show the morphology of the main ovals, the polar regions, and the footprints of Io, Europa and Ganymede. The extended Io "tail" persists for 3 h after the passage of the satellite flux tube. Multi-arc structures of varied spatial extent appear in both main auroral ovals. Inside the main ovals, intense, localized emissions are observed. In the southern aurora, an evident circular region of strong depletion of H3+ emissions is partially surrounded by an intense emission arc. The southern aurora is brighter than the north one in these observations. Similar, probably conjugate emission patterns are distinguishable in both polar regions.

We report the first spectroscopic identification of high altitude ammonia ice clouds observed in three discrete oval structures in the atmosphere of Jupiter by the Jovian InfraRed Auroral Mapper (JIRAM]) on board the Juno spacecraft. The ovals are observed at stationary positions in 2.57 micron radiance maps derived from JIRAM's spectrometer channel data acquired on Aug 2th 2016 (observation phase #2) and Aug 25th 2016 (#3) during Juno's first perijove passage. A quantitative analysis of these three features is performed by means of an inversion technique based on Bayesian method.

JIRAM is the InfraRed Auroral Mapper on board the Juno mission arrived at Jupiter on July 4 2016. The instrument is composed by two imager channels (L and M), and a spectrometer channel (SPE). L channel is centered at 3.455 ?m with a 290 nm bandwidth, devoted to the auroral emission mapping. M channel is centered is at 4.780 ?m with a 480 nm bandwidth and can sound the thermal emission from the deeper atmosphere of the planet. Their Field of View (FOV) is of the order of 1.75°×5.94° (128×432 pixels corresponding to the along and across track directions), with an Instantaneous Field of View (IFOV) of 250×250 ?rad. The spectrometer channel covers the 2.0-5.0 ?m range with a spectral sampling of about 8.99 nm/band. It is able to realize co-located imaging spectroscopy in the M-filter channel FOV by using a slit 256 samples-wide with a FOV of 3.52° and an IFOV of 250 ?rad. In this work we derive Jupiter brightness temperature maps from both the M channel (4.780 ?m) and the spectrometer (4.6-5.0 ?m range), compare their distribution and discuss the results.

The Jupiter InfraRed Auroral Mapper (JIRAM) aboard Juno observed the Jovian South Pole aurora during the first orbit of the mission. H3+ (trihydrogen cation) and CH4 (methane) emissions have been identified and measured. The observations have been carried out in nadir and slant viewing both by a L-filtered imager and a 2-5 μm spectrometer. Results from the spectral analysis of the all observations taken over the South Pole by the instrument are reported. The coverage of the southern aurora during these measurements has been partial, but sufficient to determine different regions of temperature and abundance of the H3+ ion from its emission lines in the 3-4 μm wavelength range. Finally, the results from the southern aurora are also compared with those from the northern ones from the data taken during the same perijove pass and reported by Dinelli et al. (2017).

The Juno polar orbit permitted JIRAM, the InfraRed Auroral Mapper, to observe the Jupiter poles with unprecedented resolution during the perijove passes PJ4 and PJ5. During PJ4 the coverage was complete while only partial during PJ5 due to the different attitude of the spacecraft. The images have been collected in the 4.5 -5 ?m wavelength range in several scans at different spatial resolutions varying from 14 km to 90 km, depending on the distance of the spacecraft from the planet. JIRAM could identify clusters of circumpolar cyclones (CPCs) surrounding the polar cyclones, which appear to be off the geographical poles with significant differences between north and south. Also the number of CPCs is different in the north compared to the south. The CPCs are arranged in a quasi-octagonal shape in the north while in the south they are approximately distributed on the vertices of a pentagon centered on the polar cyclone. On the basis of successive observation sequences it is possible to reconstruct the motion of the cyclones where the rotation speed can reach velocities of up to a few hundred kilometers per hour. Comparison between PJ4 and PJ5 images permits the identification of the motion of the structures in the time elapsed between the two perijove passes, currently about 53 days. Detailed results will be presented in this talk.

JIRAM (Jovian Infrared Auroral Mapper) is an imaging spectrometer on board the Juno spacecraft, specifically designed to observe the aurorae of Jupiter. Here we show results on JIRAM's data after one year of observations. The footprints of Io, Europa and Ganymede have also been observed and characterized.

The IAPS experience in the field of analysis of planetary atmospheres from visual and infrared measurements dates back to the early '90 in the frame of the IFSI participation to the Mars96 program. Since then, the forward models as well as retrieval schemes have been constantly updated and have seen a large usage in the analysis of data from Mars Express, Venus Express and Cassini missions. At the eve of a new series of missions (Juno, ExoMars, JUICE), we review the tools currently available to the Italian community, the latest developments and future perspectives. Notably, recent reanalysis of PFS-MEX and VIRTIS-VEX data \citep{Grassi2014} leaded to a full convergence of complete Bayesian retrieval schemes and approximate forward models, achieving a degree of maturity and flexibility quite close to the state-of-the-art NEMESIS package \citep{Irwin2007}. As a test case, the retrieval code for the JIRAM observations of hot-spots will be discussed, with extensive validation against simulated observations.

JIRAM (Jovian Infrared Auroral Mapper) is an imager/spectrometer on board Juno. One of its main scientific goals is to get detailed coverage of the jovian aurorae on both northern and southern polar regions, taking advantage of the highly elliptical polar orbit of the Juno spacecraft. Among the various molecular ions that emit in the electron-driven Jupiter's aurora, H3+ is observable in the JIRAM spectral range. Its main roto-vibrational band is around 2521 1/cm, composed of more than 200 possible transitions in the range 3.0-5.0 μm; observation of the infrared emission of H3+ is mainly possible in a spectral interval (3.2 to 4.0 μm) where the solar and thermal radiance emitted by the planet are very low due to the intense atmospheric methane absorption band, resulting in a high auroral contrast against Jupiter's dark disk. Hydrocarbon emission lines are also falling in the JIRAM spectral range, thus allowing to study the morphology and variability of those emitting species. Hence, JIRAM is composed of both a 2-D IR imager and a 1-D spectrometer channel in the range 2-5 um with a spectral resolution of about 9 nm and a surface resolution as low as 50 km. One of the two imager channels is centered at 3.455 µm (in the H3+ emission region), to give a context information of auroral emission, along with the spectrometer detailed measurement. In this presentation we show the first results on JIRAM's observations of the H3+ infrared emission, taken around the first Juno pericenter (August 2016) after the orbit insertion. These observations provide spatial, spectral and temporal distribution of the Jovian auroras. Successive slant and limb observations of H3+ emission are planned and will allow the study of the vertical distribution of H3+ density and temperature profile in the thermosphere.

On December 2010 a giant storm erupted in Saturn's North hemisphere. A giant vortex formed in the storm wake and persisted after the principal outburst exhausted on July 2011. The vortex had been imaged several times by the Visual and Infrared Mapping Spectrometer (VIMS) on board the Cassini probe starting from May 2011 and it was still present in observations recorded on June 2013. In this work we have analyzed the vortex data recorded by the visual channel of the spectrometer (VIMS-V) in August 2011 and January 2012. An inverse model, based on the Bayesian approach and using the Gauss-Newton iterative method to minimize the cost function, has been developed to analyze those data. The model takes advantage of the results of a supporting forward radiative transfer model which relies on the assumptions of plane parallel atmosphere, multiple scattering, Mie theory to compute particles single scattering properties, and molecular scattering adapted to Saturn's atmosphere. Applying the inverse model we could retrieve the microphysical and geometrical properties of the clouds and hazes overlying the vortex and produce spatial maps for each retrieved parameter. Thanks to this study, the vertical structure of the hazes in this region has been quantitatively addressed for the first time. The comparative analysis of the results from the two observations seems to suggest that in 6 months the atmospheric dynamics, responsible for the formation and subsistence of the vortex, is weakening and the atmosphere is returning to a more stationary state. In addition, we suggest a correction for the imaginary part of the refractive index of the tropopause haze. This new value, that allows a better convergence between observed and simulated spectra, does not yet identify a composition of the haze and further investigation is needed to understand the real nature of the need for such a modification.

En su último informe sobre seguridad ciudadana en América Latina, el PNUD (2013) resalta que, a pesar de que la región mejoró indicadores socioeconómicos habitualmente relacionados con la propagación de inseguridad, el problema no disminuyó. Por el contrario, el crimen empeoró. Para entender esta paradoja, este ensayo retoma la hipótesis de Ser violento (Moriconi, 2013) de que el verdadero problema es el colapso de la legalidad, y la violencia y el delito serían consecuencias lógicas de éste. Modificar el enfoque inicial permite diagnosticar nuevos problemas e introducir al debate variables alternativas. En este caso, se desarrolla una propuesta teórica sobre la imposibilidad de la Justicia institucional en un ambiente de alta percepción de la ilegalidad. Posteriormente, se recuperar algunas consideraciones sobre la teoría de psicología social de la Creencia en un Mundo Justo (CMJ) y se ofrece un análisis preliminar sobre cómo la naturalización de ilegalidades y las percepciones de injusticia podrían afectar seriamente la estabilidad psicológica y la autoestima de los ciudadanos. Ejemplos del caso argentino son utilizados. info:eu-repo/semantics/publishedVersion

This work is focused on the retrieval of the microphysical and geometrical properties of the clouds and hazes overlying the giant vortex observed in 2011 at Saturn, by the Visual and Infrared Mapping Spectrometer (VIMS) on board of Cassini. The retrieval algorithm is based on the optimal estimation technique [15] and takes advantage of a forward radiative transfer model developed by adapting the LibRadtran code [13] to the atmosphere of Saturn. For each of the retrieved parameters - that are effective radii, top pressures and total number densities for each considered deck - a 2D spatial map has been produced.

Limb measurements by Cassini/VIMS allow the characterization of the vertical structure of the Titan atmosphere. Spectra acquired pointing to the middlelow atmosphere are affected by strong scattering by aerosols. Their analysis requires a radiative transfer code that takes into account the multiple scattering by particles in a spherical-shell atmosphere. The use of an innovative method, based on the Monte-Carlo approach, provides important constraints on the vertical composition of the Titan atmosphere.

The InfraRed Auroral Mapper (JIRAM) is simultaneously an imager and a spectrometer on board of the Juno mission. Jupiter's reflected and emitted light in the range 2-5 ?m can be sensed through its spectral channel and H3+ emissions analyzed to retrieve auroral parameters. JIRAM is also able to map the infrared Jupiter aurora in the 3.5 ?m and planet's thermal emissions in the 5 ?m wavelength ranges through its L-band and M-band imager filters . The main scientific goals are the study of auroras, hot spots and other Jupiter atmospheric structures detectable in its working spectral range. Concurrently with the Juno Earth fly-by, that will occur on October 9th of this current year, JIRAM will observe the Moon during its transit approaching the Earth. As the instrument's temperature cannot be actively controlled, operating with a passive cooling system, the Earth will not be observed during the closest approach. A dramatic temperature increase of the instrument, far above its performance limit, is expected in fact by the illumination of the instrument's cooling radiators due to our planet reflection of the solar illumination. The Moon will be the only chance for an extended target observation that JIRAM can experience before Jupiter. Consequently, this opportunity is of pivotal importance being the only chance for a real in-flight test to verify the instrument performances and the radiometric calibration in real observational set up. The instrument will be operated in the same functional configuration that it will use at Jupiter. So far, the only absolute radiometric calibration has been performed in lab during the on ground calibration and functional test sessions. The internal calibration unit is mainly devoted to the spectral calibration checking while the absolute radiometric calibration has to verified and confirmed in flight. Results of lunar observations will be presented.

In this study the microphysical, optical and geometrical parameters obtained by Colosimo et al [5] to represent the clouds observed in the South Pole atmosphere of Saturn are used in a radiative transfer model to simulate the corresponding observations from Cassini/VIMS VIS-channel data in the wavelength range 0.84-1 micron. The disagreement between simulated and observed spectra has been interpreted taking into account the different nature of the measurements. Taking into account possible sources of discrepancies, an adjustment of the model parameters is suggested. The proposed values, reduce the difference between the simulations and the measurements from ~ 63% down to ~ 17%.

Rosetta, part of ESA's Horizon 2000 programme, will orbit and land on the comet 67P/Churyumov-Gerasimenko in May 2014. However, launched in March 2004, its trajectory has thus far muchly consisted of a series of planetary fly-bys and gravitational assists using Mars (2007) and Earth (March 2005, 2007 and 2009). During these close fly-bys Rosetta captured measurements of these planets - and of particular interest are those registed by the Visual Infrared Thermal Imaging Spectrometer VIRTIS of Earth, which were taken to help calibrate VIRTIS. Rosetta/VIRTIS measures at high spectral resolution from 0.25 - 5.0 microns, a spectral range which has been well studied by Earth observing instruments such as Meteosat Second Generation Spinning Enhanced Visible and Infrared Imager (MSG/SEVIRI) and the Advanced Along-Track Scanning Radiometer (AATSR). Earth observing instruments, whilst having superior spatio-temporal coverage to the data provided during the Rosetta/VIRTIS fly-bys, are typically constrained to measuring in only a few spectral channels. Hence, Rosetta/VIRTIS should yield more detailed spectral information than these instruments - and is a good candidate for intercomparison studies. To this end, the radiative transfer software NEMESIS (Irwin et al., 2009) is employed for the first time on Earth simulations, having been used extensively for other bodies such as Venus, Mars, Jupiter, Saturn, Neptune, Uranus and Titan. This work compares Rosetta/VIRTIS measurements with NEMESIS-simulated spectra, concentrating on quantifying the ability of NEMESIS to reproduce spectral features associated with different surface topographies (such as ocean, desert and vegetation) in combination with clear and cloudy atmospheric states. Preliminary estimations of temperature and trace-species concentrations and distributions are presented as sample products.

Stochastic partial differential equations can be used to model second order thermodynamical phase transitions, as well as a number of critical out-of-equilibrium phenomena. In (2+1) dimensions, many of these systems are conjectured (and some are indeed proved) to be described by conformal field theories. We advance, in the framework of the Martin-Siggia-Rose field theoretical formalism of stochastic dynamics, a general solution of the translation Ward identities, which yields a putative conformal energy-momentum tensor. Even though the computation of energy-momentum correlators is obstructed, in principle, by dimensional reduction issues, these are bypassed by the addition of replicated fields to the original (2+1)-dimensional model. The method is illustrated with an application to the Kardar-Parisi-Zhang (KPZ) model of surface growth. The consistency of the approach is checked by means of a straightforward perturbative analysis of the KPZ ultraviolet region, leading, as expected, to its $c=1$ conformal fixed point., Title, abstract and part of the text have been rewritten. To be published in Physical Review E.

In the following work we present a new didactic tool for planetary data visualization: the Interactive Earth Datacube that is being developed by INAF/IFSI and the Dawn EPO Team with the help of didactic specialists and teachers involved in the project. The Interactive Earth Datacube is made using VIRTIS data and is an online free access tool both for undergraduated classes and for the general public to approach planetary science and imaging spectroscopy.

In this work we have searched through Cassini/VIMS hyperspectral cubes, selecting those data which have convenient viewing geometry and which overlap with Cassini/RADAR footprints having comparable ground resolution, in order to properly look for correlations between the infrared and microwave ranges explored by the two instruments. In RADAR data we have considered two geophysical quantities: the normalized backscatter cross-section obtained from the scatterometer measurement, corrected for the incidence angle, and the brightness temperature determined from the radiometer measurement, as found in publicly available data products. In VIMS data, combining spatial and spectral information, we have selected some atmospheric windows in the spectral range between 2 and 5 ?m, providing the best optical depth to measure surface reflectance. The two RADAR parameters are combined with the VIMS data, with estimated errors, to produce an aggregate data set, that we process using multivariate classification methods to identify homogeneous taxonomic units in the multivariate space of the samples. The use of data sets from different instruments onboard the Cassini spacecraft is a necessary step towards understanding the nature and history of Titan, since correlations between different physical processes can be highlighted. A first analysis has been done with the G-mode method, which has been successfully used in the past for the classification of such diverse data sets as lunar rock samples, asteroids and planetary surfaces. Due to the large number of Titan data, the classification work is still ongoing; nevertheless the obtained results are generally in agreement with previous works aimed both to the analysis of the scatterometry data through physical models and to the correlation between SAR and radiometry data at a high resolution scale. These evidences, evaluated for the first time through a multivariate statistical method, can provide constraints on the geophysical models under development for the surface of Titan.

The Jovian InfraRed Auroral Mapper (JIRAM) is a spectroimager operating in the 25 micron range to be flown on the NASA Juno mission to Jupiter. An extensive series of tests on our direct radiative transfer codes is currently in progress, as first step in the development of analysis tools for the actual instrument measurements. We report in this work our results in two areas of interest: a. modelling of methane opacity b. validation of correlated transmittances concept in the Jupiter case.

The Juno mission to Jupiter has been planned for reaching Jupiter in October 2016. Juno's orbits have been designed for being polar. This will be a great chance for the Italian Jupiter InfraRed Auroral Mapper (JIRAM) to observe and map Jupiter auroras on the both north and south pole. JIRAM is an image spectrometer sensitive in the IR range 2-5 micron and it is provided with two focal planes: one for taking images on the L- band where the aurora IR light is emitted and the second one for making spectra with a resolution of 9 nm of part of the image. JIRAM will operate in IR wavelength and will be able to observe the H3+ emission at 3.4- 3.6 micron on the dark underlying atmosphere due to the strong absorption of methane at those wavelengths. Other mission has observed Jupiter auroras but never at such small distance and with this spectral resolution. NIMS on Galileo was the first imaging spectrometer able to observe auroras, but its spectral resolution was about three times less than JIRAM and the instrument was not able to get a large number of quality observations. Another imager spectrometer which observed Jupiter was VIMS on Cassini during its Jupiter fly-by when the spacecraft was flying at a distance of about 1 million of kilometers from the planet for a short observation at very low spatial and lower spectral resolutions. In the future, Juno will permit JIRAM to observe auroras from an unique point of view thanks to its polar orbiting and for flying so close to the planet. Juno will fly over the poles at an altitude of 1 planet radius. IR observations from JIRAM will be complemented by another instrument (UVS) observing the ultraviolet emission of the auroras.

Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole(1-4). The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50 km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition.

Venus has no seasons, slow rotation and a very massive atmosphere, which is mainly carbon dioxide with clouds primarily of sulphuric acid droplets. Infrared observations by previous missions to Venus revealed a bright 'dipole' feature surrounded by a cold 'collar' at its north pole (1–4). The polar dipole is a 'double-eye' feature at the centre of a vast vortex that rotates around the pole, and is possibly associated with rapid downwelling. The polar cold collar is a wide, shallow river of cold air that circulates around the polar vortex. One outstanding question has been whether the global circulation was symmetric, such that a dipole feature existed at the south pole. Here we report observations of Venus' south-polar region, where we have seen clouds with morphology much like those around the north pole, but rotating somewhat faster than the northern dipole. The vortex may extend down to the lower cloud layers that lie at about 50km height and perhaps deeper. The spectroscopic properties of the clouds around the south pole are compatible with a sulphuric acid composition.

International audience

International audience

International audience