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Neptune's tropospheric winds are among the most intense in the Solar System, but the dynamical mechanisms that produce them remain uncertain. Measuring wind speeds at different pressure levels may help understand the atmospheric dynamics of the planet. The goal of this work is to directly measure winds in Neptune's stratosphere with ALMA Doppler spectroscopy. We derived the Doppler lineshift maps of Neptune at the CO(3-2) and HCN(4-3) lines at 345.8 GHz ($\lambda$~0.87 mm) and 354.5 GHz (0.85 mm), respectively. For that, we used spectra obtained with ALMA in 2016 and recorded with a spatial resolution of ~0.37" on Neptune's 2.24" disk. After subtracting the planet solid rotation, we inferred the contribution of zonal winds to the measured Doppler lineshifts at the CO and HCN lines. We developed an MCMC-based retrieval methodology to constrain the latitudinal distribution of wind speeds. We find that CO(3-2) and HCN(4-3) lines probe the stratosphere of Neptune at pressures of $2^{+12}_{-1.8}$ mbar and $0.4^{+0.5}_{-0.3}$ mbar, respectively. The zonal winds at these altitudes are less intense than the tropospheric winds based on cloud tracking from Voyager observations. We find equatorial retrograde (westward) winds of $-180^{+70}_{-60}$ m/s for CO, and $-190^{+90}_{-70}$ m/s for HCN. Wind intensity decreases towards mid-latitudes, and wind speeds at 40$^\circ$S are $-90^{+50}_{-60}$ m/s for CO, and $-40^{+60}_{-80}$ m/s for HCN. Wind speeds become 0 m/s at about 50$^\circ$S, and we find that the circulation reverses to a prograde jet southwards of 60$^\circ$S. Overall, our direct stratospheric wind measurements match previous estimates from stellar occultation profiles and expectations based on thermal wind equilibrium. These are the first direct Doppler wind measurements performed on the Icy Giants, opening a new method to study and monitor their stratospheric dynamics., Comment: Accepted for publication in A&A Letters on 10/05/2023. 8 pages, 1 Table, 5 Figures

Several science Working Groups (WG) were formed in 2019 within the Ariel Mission Consortium to help prepare the RedBook (Tinetti et al. ESA/SCI(2020)1), defining the science cases, and to contribute to address three fundamental questions 1) what exoplanets are made of; 2) how they formed and 3) how they evolve. Among those WGs, “Synergies between Solar System planets and exoplanets” was set-up to foster collaboration between the scientific community working on Solar System Planets atmospheres and the new growing community of the Ariel Science Team. We show here an overview of on-going studies and future projects foreseen by WG members, mostly focused on using our Solar System planets as proxies to develop and test tools to support Ariel science cases

Context. Infrared spectroscopy over a wide spectral range and at the highest resolving powers (R > 70 000) has proved to be one of the leading techniques to unveil the atmospheric composition of dozens of exoplanets. The recently upgraded spectrograph CRIRES instrument at the Very Large Telescope (CRIRES+) was operative for a first science verification in September 2021, and its new capabilities in atmospheric characterization were ready to be tested. Aims. We analyzed transmission spectra of the hot Saturn WASP-20b in the K band (1981–2394 nm) that were acquired with CRIRES+ with the aim to detect the signature of H2O and CO. Methods. We used a principal component analysis to remove dominant time-dependent contaminating sources such as telluric bands and the stellar spectrum. We extracted the planet spectrum by cross-correlating observations with 1D and 3D synthetic spectra, without circulation. Results. We present the tentative detection of molecular absorption from water vapor at a signal-to-noise ratio equal to 4.2 and 4.7 by using only H2O 1D and 3D models, respectively. The peak of the cross-correlation function occurred at the same rest-frame velocity for both model types (Vrest = −1 ± 1 km s−1 ) and at the same projected orbital velocity of the planet, but with different error bands (1D model: Kp = 131 −29+18 k ms −1; 3D: Kp = 131 −39+23 k ms −1). Our results agree with the result expected in the literature (132.9 ± 2.7 km −1). Conclusions. Although the observational conditions were not ideal and we had problems with the pipeline in calibrating and reducing our raw data set, we obtained the first tentative detection of water in the atmosphere of WASP-20b. We suggest a deeper analysis and additional observations to confirm our results and unveil the presence of CO.

International audience; We have built a new 3D Global Climate Model (GCM) to simulate Pluto as observed by New Horizons in 2015. All key processes are parametrized on the basis of theoretical equations, including atmospheric dynamics and transport , turbulence, radiative transfer, molecular conduction, as well as phases changes for N 2 , CH 2 and CO. Pluto's climate and ice cycles are found to be very sensitive to model parameters and initial states. Nevertheless, a reference simulation is designed by running a fast, reduced version of the GCM with simplified atmospheric transport for 40,000 Earth years to initialize the surface ice distribution and sub-surface temperatures, from which a 28-Earth-year full GCM simulation is performed. Assuming a topographic depression in a Sputnik-planum (SP)-like crater on the anti-Charon hemisphere, a realistic Pluto is obtained, with most N 2 and CO ices accumulated in the crater, methane frost covering both hemispheres except for the equatorial regions, and a surface pressure near 1.1 Pa in 2015 with an increase between 1988 and 2015, as reported from stellar occultations. Temperature profiles are in qualitative agreement with the observations. In particular, a cold atmospheric layer is obtained in the lowest kilometers above Sputnik Planum, as observed by New Horizons's REX experiment. It is shown to result from the combined effect of the topo-graphic depression and N 2 daytime sublimation. In the reference simulation with surface N 2 ice exclusively present in Sputnik Planum, the global circulation is only forced by radiative heating gradients and remains relatively weak. Surface winds are locally induced by topography slopes and by N 2 condensation and sublimation around Sputnik Planum. However, the circulation can be more intense depending on the exact distribution of surface N 2 frost. This is illustrated in an alternative simulation with N 2 condensing in the South Polar regions and N 2 frost covering latitudes between 35 • N and 48 • N. A global condensation flow is then created, inducing strong surface winds everywhere, a prograde jet in the southern high latitudes, and an equatorial superrotation likely forced by barotropic instabilities in the southern jet. Using realistic parameters, the GCM predict atmospheric concentrations of CO and CH 4 in good agreement with the observations. N 2 and CO do not condense in the atmosphere, but CH 4 ice clouds can form during daytime at low altitude near the regions covered by N 2 ice (assuming that nucleation is efficient enough). This global climate model can be used to study many aspects of the Pluto environment. For instance, organic hazes are included in the GCM and analysed in a companion paper (Bertrand and Forget, Icarus, this issue).

We have performed periodic ab initio calculations to study the adsorption of hydrogen atoms on TiO2(1 1 0) rutile surface. Two adsorption modes have been considered on slabs. Even if the presence of atomic hydrogen on the surface does not arise from the H2 dissociation, we will refer to the H–H cleavage for the analysis. Hence, in the H mode, the heterolytic cleavage of H2 yields to H+ and H−. The proton interacts with the most basic oxygen atoms of the surface, while H− adsorbs on a metal cation which is the Lewis acidic site. In the R mode, two H+ fix on top of the outer surface anions and two Ti(IV) are reduced to Ti(III). Our calculated adsorption energies values show that the R mode is the most favorable. The surface reduction is only apparent through the spin polarization and does not lead to a full electron charge transfer from the hydrogen atoms to the surface. The change of the electronic state and of the adsorption strength with the slab thickness is presented. Using NH3 as a probe molecule to test the surface acidity, we show that the Ti reduction modifies its reactivity. Surface relaxation significantly contributes to increase the adsorption strengths; however it does not modify the qualitative conclusions.

P(VF2-TrFE) pyroelectric copolymer is chosen for its high level of compatibility with existing microelectronics processes, and convenient electrical properties for infrared (IR) 8 to 14 μm imagery in the performance range of NETD 0.1 K to 1 K. Low cost sensors are achieved thanks to the monolithic silicon wafer processing, standard package assembly, and uncooled operations, and are nowadays compatible with large volume user's needs and market prices. The paper describes pyroelectric device trade-offs, architecture and process. Based on the interline architecture, the sensor performances of the TH 7441A 128 x 128 area array infrared detector will be presented: compatible with 1 optics, the square array is made of a 80 x 80 μm 2 pixel, on a pixel pitch of 85 μm. The CCD multiplexer using patented on-site processing is designed to deliver the image information at the maximum rate of 50 image/s. Lower rates are achievable. Imaging performances are the following: a NETD of 1.6 K is achieved with an integration time of 10 ms and the use of a f/l optics presenting a transmission of 0.8.

In this review, we summarize our present knowledge of the behaviour of the mass-radius relationship from solar-type stars down to terrestrial planets, across the regime of substellar objects, brown dwarfs and giant planets. Particular attention is paid to the identification of the main physical properties or mechanisms responsible for this behaviour. Indeed, understanding the mechanical structure of an object provides valuable information about its internal structure, composition and heat content as well as its formation history. Although the general description of these properties is reasonably well mastered, disagreement between theory and observation in certain cases points to some missing physics in our present modelling of at least some of these objects. The mass-radius relationship in the overlaping domain between giant planets and low-mass brown dwarfs is shown to represent a powerful diagnostic to distinguish between these two different populations and shows once again that the present IAU distinction between these two populations at a given mass has no valid foundation., Comment: Cool Stars, Stellar Systems and the Sun 15, invited review

The TH74KB41A camera is designed for the THOMSON-CSF Semiconducteurs Specifiques (TCS) TH7441A pyroelectric IR sensor, optimized for the wavelength range 8 to 14 micrometers. This monolithic area sensor is made of 128 by 128 pixels (85 micrometers by 85 micrometers) compatible with a one inch diameter optic, and operates at ambient temperature. The camera is optimized to operate with a short integration period -- 10 ms -- allowing 50 frames per second, then compatible with a wide range of applications, including real-time imaging. Three video outputs are available: one 10-bit unprocessed image output every 10 ms, one 8-bit processed image every 20 ms, and one composite analog video signal using a 128 by 128 zone of the display. Eight-bit and analog outputs are obtained by summing the two successive fields -- alternately positive and negative. The 10-bit output delivers successively these positive and negative fields, 10 ms each. It is possible to select an analog gain 3 or 6 and a digital gain of 1, half, quarter or an eighth. Offset may be adjusted to fit the temperature range to be viewed in accordance with the chosen gain. The camera also produces pixel, line, and frame pulses to ease synchronization of an optional frame grabber. Power consumption is as low as 12.5 W, including chopper power supply. The useful scene dynamic range is plus or minus 170 degrees around the ambient temperature. With an f/1 optic -- optics transmission is 0.8 -- the NETD is around 1.5 K and the recognition 0.75 K. The contrast transfer function at Nyquist frequency -- 5.9 line pairs per mm -- is 38%. The small size of this lightweight camera body (200 mm by 125 mm by 60 mm without lenses) together with its low power consumption allow easy use everywhere. This camera benefits from the pyroelectric area sensor and does not use any cooling. This camera, quite cheaper than a camera using a cooled detector, is well suited to a wide range of applications such as laser beam profile analysis, IR machine vision in the industrial field -- useful for process control, security, night vision, etc., -- fire fighting or prevention, search and rescue in poor vision environment, medical diagnosis, etc.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Although a relation between child abuse and developmental disabilities has been established, information about the health and developmental status of children referred to child protective services is not adequately obtained. Case records of 150 children identified to child protective services were reviewed in order to determine the availability of health and developmental information. A screening protocol was developed for the purpose of reviewing case records that has potential for use by child protective services workers.

Lambert-Eaton syndrome is a myasthenia-like syndrome of paraneoplastic origin which is often associated with anaplastic small-cell lung cancer. It seems to be an autoimmune disease responsible for a deficit of acetylcholine ejection in the motor end plate. On the occasion of two recent cases, we review the clinical, physiopathological and diagnostic aspects of this paraneoplastic syndrome.

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During the last quarter of the nineteenth century the theory of evolution profoundly influenced American thought. In the form of Social Darwinism it significantly shaped views on race, civilization, and political theory. Sociology and psychology were developing concurrently as disciplines. All of these were destined to have an effect upon education, for many intellectuals believed that science in general and evolutionary theory in particular were directly applicable to all areas of thought. Among the advocates of such a role for science and evolutionary theory was Joseph LeConte, whose views on the subject are outlined and compared with his contemporaries.

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