Hazes and clouds in a singular triple vortex in Saturn's atmosphere from HST/WFC3 multispectral imaging

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Reanalyzing Jupiter ISO/SWS Data through a More Recent Atmospheric Model

The study of isotopic ratios in planetary atmospheres gives an insight into the formation history and evolution of these objects. The more we can constrain these ratios, the better we can understand the history and future of our solar system. To help in this endeavour, we used Infrared Space Observatory Short Wavelength Spectrometer (ISO/SWS) Jupiter observations in the 793–1500 cm−1 region together with the Nonlinear Optimal Estimator for MultivariatE Spectral analySIS (NEMESIS) radiative transfer suite to retrieve the temperature–pressure profile and the chemical abundances for various chemical species. We also used the 1500–2499 cm−1 region to determine the cloud and aerosol structure of the upper troposphere. We obtained a best-fit simulated spectrum with 2/=0.47 for the 793–1500 cm−1 region and 2/=0.71 for the 1500–2499 cm−1 region. From the retrieved methane abundances, we obtained, within a 1 uncertainty, a 12C/13C ratio of 84 ± 27 and a D/H ratio of (3.5 ± 0.6) × 10−5, and these ratios are consistent with other published results from the literature.This research was funded by the Portuguese Fundação Para a Ciência e Tecnologia through the research grants UIDB/04434/2020 and UIDP/04434/2020 as well as a fellowship grants 2021.04584.BD and 2022.09859.BD

Uranus's Northern Polar Cap in 2014

In October and November 2014, spectra covering the 1.436 – 1.863-μm wavelength range from the SINFONI Integral Field Unit Spectrometer on the Very Large Telescope showed the presence of a vast bright North polar cap on Uranus, extending northward from about 40ºN and at all longitudes observed. The feature, first detected in August 2014 from Keck telescope images, has a morphology very similar to the southern polar cap that was seen to fade before the 2007 equinox. At strong methane-absorbing wavelengths (for which only the high troposphere or stratosphere is sampled) the feature is not visible, indicating that it is not a stratospheric phenomenon. We show that the observed northern bright polar cap results mainly from a decrease in the tropospheric methane mixing ratio, rather than from a possible latitudinal variation of the optical properties or abundance of aerosol, implying an increase in polar downwelling near the tropopause level

Probable detection of hydrogen sulphide (H₂S) in Neptune’s atmosphere

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DIE EINSCHRÄNKUNG DER VERWENDUNG DER GLAGOLIZA AUF DER SYNODE VON ZADAR 1460

U radu se prikazuje odluka Zadarske sinode od 4. prosinca 1460. na kojoj je nadbiskup Mafej Vallaresso pokušao suzbiti upotrebu liturgije na crkvenoslavenskom jeziku hrvatske redakcije (lingua sclava). Sinodalni akti nisu danas sačuvani već je dostupan samo jedan dio sinodalnog kanona u dvije verzije. Originalnu verziju donosi Carlo F. Bianchi, dok je drugu, neznatno izmijenjenu, pribilježio Ivan Zanotti – Tanzlingher. Poslije interpretcije i konzultacije mjerodavnih vrela zaključuje se kako sinodalna odredba nije posve dokidala liturgijska slavlja na hrvatskom jeziku nego je samo na sinodi poduzet pothvat prostornog i vremenskog suzbijanja »glagoljaške liturgije«. Zadarski su nadbiskupi pokušavali tijekom XVI. stoljeća suzbiti glagoljicu na teritoriju nadbiskupije, ali – kako to pokazuju dostupna vrela – nisu imali znatnijeg uspjeha.In this short discussion author analyzes decisions of the Zadar synod that was held on 4th December 1460. At this diocese council archbishop Mafeo Vallaresso tried to suppress local custom of having the holy service in Church-Slavonic language. The acts from this synod unfortunately are not completely preserved but only one article De celebratione missarum et elebrandi divina official today is known in two versions. The first, and presumably original, version was brought to us by Carlo F. Bianchi, and the second one, just slightly modified, was noted by Ivan Zanotti-Tanzlingher. The both notes deliver basically the same information, and differ only regarding the beginning of this act. Archbishop Vallaresso deeply influenced ecclesiastical life of his diocese at his time: he renovated archbishopric palace, ordered a new bell for the cathedral’s bell tower, and restored organ in the cathedral of St. Anastasia. Still, even though he was a typical renaissance man, he did not care much about the specific local tradition of Zadar and deeply rooted Croatian language. Moreover, through the synod he tried to restrain Glagolitic liturgy only to two town churches: St. Donatus (Holy Trinity) and St. Mary the Great. Similarly, a century later, archbishops of the sixteenth century also tried to suppress Glagolitic script in Zadar, for example on the synods of 1566 and 1594. However, in spite of their endeavors, as it is clearly visible from the extant sources, they did not have much success, and Church Slavonic remained an integral part of local liturgy until the reform of the Second Vatican Council.In dieser kleinen Abhandlung wird die synodale Entscheidung über die Einschränkung der Liturgie in der kirchenslavischen Sprache (der kroatischen Redaktion) analysiert. Der venezianische Patrizier und der Erzbischof von Zadar, Maphäus Vallaresso (1450-1496) hat am 4. Dezember 1460 die Synode in Zadar einberufen; ihre Akten oder Entscheidungen sind nicht erhalten, nur ein kleiner Ausschnitt aus dem Kanon »De celebratione missarum et celebrandi divina officia«. Dieser ist heute in zwei Versionen zugänglich, die sich sprachlich nur geringfügig voneinander unterscheiden. Die Originalversion hat schon Carlo F. Bianchi veröffentlicht und die zweite hat Johannes Zanotti – Tanzlingher in seinem Werk Epitome synodorum dioecesis Iadrensis vermerkt. Die synodale Entscheidung versucht die Liturgie in der kirchenslavischen Sprache der kroatischen Redaktion für bestimmte Zeit nur auf zwei Kirchen in Zadar zu reduzieren: Die Kirche der Hl. Dreifaltigkeit (heute hl. Donat) und die Kirche der hl. Maria. Diese Entscheidung ließ sich nicht verwirklichen, da die Liturgie in lingua slava (d. h. in kroatischer Sprache) eine lange Tradition hat und in allen Pfarreien verbreitet war. Die Erzbischöfe von Zadar, Mutius Callinus (1555-1566) und auch Aloysius Molinus (1592-1595) haben diese Entscheidung auf den Synoden 1566 und 1594 noch einmal verbindlich erklärt; die Versuche sind gescheitert. Erzbischof Oktavian Garzzadoro (1623-1644), der aus gesundheitlichen Gründen Papst Urban VIII. um die Entbindung von den Pflichten bat, fügte seiner Begründung hinzu, dass er die Sprache der Gläubigen seines Bistums nicht versteht. Dies ist ein klarer Beweis dafür, dass in Zadar die Bevölkerung kroatisch gesprochen hat und die Liturgie bis zur Reform des II. Vatikanischen Konzils in der Landessprache gefeiert wurde

ALMA detection and astrobiological potential of vinyl cyanide on Titan

Recent simulations have indicated that vinyl cyanide is the best candidate molecule for the formation of cell membranes/vesicle structures in Titan's hydrocarbon-rich lakes and seas. Although the existence of vinyl cyanide (C2H3CN) on Titan was previously inferred using Cassini mass spectrometry, a definitive detection has been lacking until now. We report the first spectroscopic detection of vinyl cyanide in Titan's atmosphere, obtained using archival data from the Atacama Large Millimeter/submillimeter Array (ALMA), collected from February to May 2014. We detect the three strongest rotational lines of C2H3CN in the frequency range of 230 to 232 GHz, each with >4σ confidence. Radiative transfer modeling suggests that most of the C2H3CN emission originates at altitudes of ≳200 km, in agreement with recent photochemical models. The vertical column densities implied by our best-fitting models lie in the range of 3.7 × 1013 to 1.4 × 1014 cm-2. The corresponding production rate of vinyl cyanide and its saturation mole fraction imply the availability of sufficient dissolved material to form ~107 cell membranes/cm3 in Titan's sea Ligeia Mare

Latitudinal Variations in Methane Abundance, Aerosol Opacity and Aerosol Scattering Efficiency in Neptune's Atmosphere Determined From VLT/MUSE

Spectral observations of Neptune made in 2019 with the Multi Unit Spectroscopic Explorer (MUSE) instrument at the Very Large Telescope (VLT) in Chile have been analyzed to determine the spatial variation of aerosol scattering properties and methane abundance in Neptune's atmosphere. The darkening of the South Polar Wave at ∼60°S, and dark spots such as the Voyager 2 Great Dark Spot is concluded to be due to a spectrally dependent darkening (λ 650 nm. We find the properties of an overlying methane/haze aerosol layer at ∼2 bar are, to first-order, invariant with latitude, while variations in the opacity of an upper tropospheric haze layer reproduce the observed reflectivity at methane-absorbing wavelengths, with higher abundances found at the equator and also in a narrow “zone” at 80°S. Finally, we find the mean abundance of methane below its condensation level to be 6%–7% at the equator reducing to ∼3% south of ∼25°S, although the absolute abundances are model dependent.We are grateful to the United Kingdom Science and Technology Facilities Council for funding this research (Irwin: ST/S000461/1, Teanby: ST/R000980/1). Glenn Orton was supported by funding to the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). Leigh Fletcher and Mike Roman were supported by a European Research Council Consolidator Grant (under the European Union's Horizon 2020 research and innovation programme, grant agreement no. 723890) at the University of Leicester. Santiago Pérez-Hoyos and Agustin Sánchez-Lavega are supported by the Spanish project PID2019-109467GB-I00 (MINECO/FEDER, UE), Elkartek21/87 KK-2021/00061 and Grupos Gobierno Vasco IT-1742-22

The formation and evolution of Titan's winter polar vortex

The polar hot-spot appeared in Titan after equinox in 2010 suddenly cooled in early 2012, which wasn’t predicted by models. Here the authors use observations to show that the increase in trace gases during the hot-spot resulted in radiative cooling feedback

An intense narrow equatorial jet in Jupiter’s lower stratosphere observed by JWST

The atmosphere of Jupiter has east–west zonal jets that alternate as a function of latitude as tracked by cloud motions at tropospheric levels. Above and below the cold tropopause at ~100 mbar, the equatorial atmosphere is covered by hazes at levels where thermal infrared observations used to characterize the dynamics of the stratosphere lose part of their sensitivity. James Webb Space Telescope observations of Jupiter in July 2022 show these hazes in higher detail than ever before and reveal the presence of an intense (140 m s−1) equatorial jet at 100–200 mbar (70 m s−1 faster than the zonal winds at the cloud level) that is confined to ±3° of the equator and is located below stratospheric thermal oscillations that extend at least from 0.1 to 40 mbar and repeat in multiyear cycles. This suggests that the new jet is a deep part of Jupiter’s Equatorial Stratospheric Oscillation and may therefore vary in strength over time.JWST-ERS-01373, NASA/ESA Hubble Space Telescope programmes no. 16913, 15502 and 16790, PID2019-109467GB-I00 funded by MCIN/AEI/10.13039/501100011033/, Grupos Gobierno Vasco IT1742-22. I.d.; European Research Council Consolidator Grant (under the European Union’s Horizon 2020 research and innovation programme, grant agreement no. 723890), STFC PhD Studentship, NASA grants 80NSSC21K1418 and 80NSSC19K0894

Highly-parallelized simulation of a pixelated LArTPC on a GPU

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype