Quando um discurso geralmente valorizado não é bem‑ vindo: o caso da expressão da crença num mundo geral justo por um membro (fictício) da élite financeira

We aim to show that an idea that is generally valued (“just world”) when expressed by ordinary people becomes paradoxically a sign of immorality when expressed by the finance elite. Participants from Portugal and Spain read the fictitious case (inspired by real events) of “George M.”, a stereotypical member of the finance elite. Participants randomly read that the target had expressed the idea that the world is fair or unfair to people in general. Then, they indicated how immoral the target was and how much they wished him various outcomes. Comparing the target who expressed “the world is not just”, the one who expressed “the world is just” was judged as more immoral. Higher immoral judgements predicted higher wishes of negative outcomes. These results advise the elite against using moralizing discourses, which are likely to backfireinfo:eu-repo/semantics/publishedVersio

Saturn's neutral torus versus Jupiter's plasma torus

With the recent discovery of an atmospheric plume of H2O it is thought that Enceladus could deliver as much a 300 kg/s of neutral gas to Saturn's inner magnetosphere. Io is the source of roughly 1 ton/s of sulfur and oxygen gas at Jupiter. Despite the apparent similarity, the neutral/ion ratio at Saturn is 3 orders of magnitude higher than at Jupiter. We explore the flow of mass and energy at Saturn and Jupiter using a simplified homogeneous physical chemistry model to understand why these two system are so different. Our results suggest that ionization at Saturn is fundamentally limited by the slower corotational flow velocity at Enceladus, resulting in a factor of 4 lower ion pickup temperature. The net result of cooler ions at Enceladus is a cooler thermal electron population (∼2 eV) that is insufficient to generate significant ionization

Comparative study of the power transferred from satellite-magnetosphere interactions to auroral emissions

Io's interaction with the Jovian magnetosphere generates a power of about 1012 W which propagates as Alfvn waves along the magnetic field lines and is partly transferred to electrons, resulting in intense auroral emissions. A recent study of the power transmission along the Io flux tube and of the electron acceleration at high latitudes showed that the power of the observed emissions is well explained by assuming filamentation of the Alfvn waves in the torus and the acceleration of the electrons at high latitude. At Jupiter, UV footprints related to Europa and Ganymede have also been observed. At Saturn recent observations revealed a weak UV footprint of Enceladus. We apply the Io interaction model to the Europa and Enceladus interactions. We show that the Alfvn wave filamentation leads to a precipitating electron power consistent with the power of the observed UV footprints

Generation of parallel electric fields in the Jupiter-Io torus wake region

Infrared and ultraviolet images have established that auroral emissions at Jupiter caused by the electromagnetic interaction with Io not only produce a bright spot, but an emission trail that extends in longitude from Io's magnetic footprint. Electron acceleration that produces the bright spot is believed to be dominated by Alfvén waves whereas we argue that the trail or wake aurora results from quasi-static parallel electric fields associated with large-scale, field-aligned currents between the Io torus and Jupiter's ionosphere. These currents ultimately transfer angular momentum from Jupiter to the Io torus. We examine the generation and the impact of the quasi-static parallel electric fields in the Io trail aurora. A critical component to our analysis is a current-voltage relation that accounts for the low-density plasma along the magnetic flux tubes that connect the Io torus and Jupiter. This low-density region, ∼2 Rj from Jupiter's center, can significantly limit the field-aligned current, essentially acting as a "high-latitude current choke." Once parallel electric fields are introduced, the governing equations that couple Jupiter's ionosphere to the Io torus become nonlinear and, while the large-scale behavior is similar to that expected with no parallel electric field, there are substantial deviations on smaller scales. The solutions, bound by properties of the Io torus and Jupiter's ionosphere, indicate that the parallel potentials are on the order of 1 kV when constrained by peak energy fluxes of a few milliwatts per square meter. The parallel potentials that we predict are significantly lower than earlier reports

Ultraviolet observations of the Saturnian north aurora and polar haze distribution with the HST-FOC

Near simultaneous observations of the Saturnian H2 north ultraviolet aurora and the polar haze were made at 153 nm and 210 nm respectively with the Faint Object Camera on board the Hubble Space Telescope. The auroral observations cover a complete rotation of the planet and, when co-added, reveal the presence of an auroral emission near 80 deg N with a peak brightness of about 150 kR of total H2 emission. The maximum optical depth of the polar haze layer is found to be located approximately 5 deg equatorward of the auroral emission zone. The haze particles are presumably formed by hydrocarbon aerosols initiated by H2+ auroral production. In this case, the observed haze optical depth requires an efficiency of aerosol formation of about 6 percent, indicating that auroral production of hydrocarbon aerosols is a viable source of high-latitude haze

Energetic proton depletion near Io: atmospheric charge exchange and inhomogeneous magnetic and electric fields

Stars and planetary system

Study of the vertical structure of Saturn's atmosphere using HST/WFPC2 images

We have studied the vertical structure of hazes at six different latitudes (-60degrees, -50degrees, -30degrees, -10degrees, +30degrees, and +50degrees) on Saturn's atmosphere. For that purpose we have compared the results of our forward radiative transfer model to limb-to-limb retlectivity scans at four different wavelengths (230, 275, 673.2, and 893 nm). The images were obtained with the Hubble Space Telescope Wide Field Planetary Camera 2 in September 1997, during fall on Saturn's northern hemisphere. The spatial distribution of particles appears to be very variable with latitude both in the stratosphere and troposphere. For the latitude range +50degrees to -50degrees, an atmospheric structure consisting of a stratospheric haze and a tropospheric haze interspersed by clear gas regions has been found adequate to explain the center to limb reflectivities at the different wavelengths. This atmospheric structure has been previously used by Ortiz et al. (1996, Icarus 119, 53-66) and Stam et al. (2001, Icarus 152, 407-422). In this work the top of the tropospheric haze is found to be higher at the southern latitudes than at northern latitudes. This hemispherical asymmetry seems to be related to seasonal effects. Different latitudes experience different amount of solar insolation that can affect the atmospheric structure as the season varies with time. The haze optical thickness is largest (about 30 at 673.2 nm) at latitudes +/-50 and -10 degrees, and smallest (about 18) at 30 degrees. The stratospheric haze is found to be optically thin at all studied latitudes from -50 to +50 degrees being maximum at -10degrees (r = 0.033). At -60degrees latitude, where the UV images show a strong darkening compared to other regions on the planet, the cloud structure is remarkably different when compared to the other latitudes. Here, aerosol and gas are found to be uniformly mixed down to the 400 mbar level. (C) 2004 Elsevier Inc. All rights reserved

SIMULTANEOUS OBSERVATIONS OF THE SATURNIAN AURORA AND POLAR HAZE WITH THE HST/FOC

peer reviewedNear simultaneous observations of the Saturnian H-2 north ultraviolet aurora and the polar haze were made at 153 nm and 210 nm respectively with the Faint Object Camera on board the post-COSTAR Hubble Space Telescope. The auroral observations cover a complete rotation of the planet and, when co-added, they reveal the presence of an auroral emission near 80 degrees N with a brightness of about 150 kR of total H-2 emission. The maximum vertical optical depth at 210 nm is found to be located similar to 5 degrees equatorward of the auroral emission zone. The haze particles are presumably formed by hydrocarbon aerosols initiated by H2+ auroral production. In this case, the 3 x 10(^10) W of H2 emission observed with the FOG, combined with the deduced haze optical depth requires an efficiency of aerosol formation of about 7%. This result indicates that auroral production of hydrocarbon aerosols is a viable source of high-latitude haze

The Io UV footprint: Location, inter-spot distances and tail vertical extent

The Io footprint (IFP) consists of one or several spots observed in both jovian hemispheres and is related to the electromagnetic interaction between Io and the magnetosphere. These spots are followed by an auroral curtain, called the tail, extending more than 90° longitude in the direction of planetary rotation. We use recent Hubble Space Telescope images of Jupiter to analyze the location of the footprint spots and tail as a function of Io's location in the jovian magnetic field. We present here a new IFP reference contour---the locus of all possible IFP positions---with an unprecedented accuracy, especially in previously poorly covered sectors. We also demonstrate that the lead angle - the longitudinal shift between Io and the actual IFP position - is not a reliable quantity for validation of the interaction models. Instead, the evolution of the inter-spot distances appears to be a better diagnosis of the Io-Jupiter interaction. Moreover, we present observations of the tail vertical profiles as seen above the limb. The emission peak altitude is ~900 km and remains relatively constant with the distance from the main spot. The altitudinal extent of the vertical emission profiles is not compatible with precipitation of a mono-energetic electron population. The best fit is obtained for a kappa distribution with a characteristic energy of ~70 eV and a spectral index of 2.3. The broadness of the inferred electron energy spectrum gives insight into the physics of the electron acceleration mechanism at play above the IFP tail