Article
Astronomy & Astrophysics
B. Charnay, G. Tobie, S. Lebonnois, R. D. Lorenz
Summary: By studying Titan's atmosphere, the Dragonfly mission can provide valuable constraints on the interior of Titan.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. Rengel, D. Shulyak, P. Hartogh, H. Sagawa, R. Moreno, C. Jarchow, D. Breitschwerdt
Summary: The aim of this study was to measure the vertical distribution of HCN on Titan's stratosphere using ground-based submillimetre observations acquired quasi-simultaneously with the Herschel ones. The results showed consistent HCN abundance profiles and provided valuable information for the improvement of photochemical models. The study received a score of 9 out of 10 for its importance in understanding the vertical distribution of HCN in Titan's stratosphere.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
N. L. Rossignoli, R. P. Di Sisto, M. G. Parisi
Summary: By studying the impact crater counts and erosion processes on Titan, we can estimate its surface age and understand the role of centaur objects in impacts.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Benno A. Neuenschwander, Ravit Helled
Summary: This paper presents empirical structure models of Uranus and Neptune and predicts their rotation periods and wind depths by using higher order gravitational coefficients. The study finds that faster rotation and deep winds favor centrally concentrated density distributions. Accurate measurements of the gravity field and moment of inertia can constrain their internal structures and wind depths.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Yutian Cao, Dandan Niu, Wenjun Liang, Jun Cui, Xiaoshu Wu, Xin Wan, Jiahao Zhong, Lei Li, Zhaojin Rong, Yong Wei
Summary: Thermal electron depression and energetic electron depletion are observed in the nightside Martian ionosphere. While energetic electron depletion has been extensively studied, there is limited research on thermal electron depression and the correlation between the two is unknown. Through Mars Express total electron content (TEC) measurements, a large number of TEC depression features are identified, with large amplitude depression being more frequently observed near strong magnetic fields and small amplitude depression uniformly distributed across the Martian surface.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Ludwig Scheibe, Nadine Nettelmann, Ronald Redmer
Summary: Thermal evolution models of Uranus and Neptune suggest that their luminosities are inconsistent with the classical assumption of an adiabatic interior, with the influence of a thermally conductive boundary layer being a significant factor. Even a thin conductive layer of a few kilometers can greatly affect planetary cooling, resulting in either brighter or fainter appearances compared to the adiabatic case. The models also indicate that Uranus may have been in equilibrium with solar flux for a longer period of time.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Richard Hobbs, Paul B. Rimmer, Oliver Shorttle, Nikku Madhusudhan
Summary: A new network of atmospheric sulfur reactions was proposed and validated, showing significant impact on gas mixing ratios under specific conditions and causing major changes in the abundance of specific species. Accurate understanding of sulfur chemistry in hot and warm Jupiter atmospheres requires experimental measurements of reaction rates.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Hao Gu, Jun Cui, Dandan Niu, Jiang Yu
Summary: The study suggests that on Venus, collision by hot O likely plays a dominant role in driving total atmospheric hydrogen and helium escape at the present epoch, with a reduction in escape flux for all species during high solar activities. Substantial variations are also revealed by the calculations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Xu Huang, Hao Gu, Jun Cui, Xiaoshu Wu, Mingyang Sun
Summary: This study evaluates the effects of the 2018 global dust storm on the photochemical escape of atomic C, N, and O on Mars. It uses multi-instrument measurements and a one-dimensional Monte Carlo model to calculate the escape probability profile and derive the photochemical escape rates. The results show that the GDS-induced C, N, and O escape is generally reduced by about 30-40% compared to the pre-GDS state, contrary to the well-known result of GDS-induced strong enhancement of atomic H escape.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Ye Yuan, Fan Li, Yanning Fu, Jian Chen
Summary: Through new observations and ephemerides, a dynamic model update has effectively improved the ephemerides for Triton and Nereid. The model fitting process led to the determination of Neptune's pole orientation, providing refined geometric descriptions.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
M. Lampon, M. Lopez-Puertas, S. Czesla, A. Sanchez-Lopez, L. M. Lara, M. Salz, J. Sanz-Forcada, K. Molaverdikhani, A. Quirrenbach, E. Palle, J. A. Caballero, Th. Henning, L. Nortmann, P. J. Amado, D. Montes, A. Reiners, I. Ribas
Summary: Hydrodynamic escape is the most efficient atmospheric mechanism of planetary mass loss, with three regimes identified: energy-limited, recombination-limited, and photon-limited. This study provides evidence of these regimes in exoplanets HD 209458 b, HD 189733 b, and GJ 3470 b.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
L. Fossati, F. Biassoni, G. M. Cappello, F. Borsa, D. Shulyak, A. S. Bonomo, D. Gandolfi, F. Haardt, T. Koskinen, A. F. Lanza, V. Nascimbeni, D. Sicilia, M. Young, G. Aresu, A. Bignamini, M. Brogi, I. Carleo, R. Claudi, R. Cosentino, G. Guilluy, C. Knapic, L. Malavolta, L. Mancini, D. Nardiello, M. Pinamonti, L. Pino, E. Poretti, M. Rainer, F. Rigamonti, A. Sozzetti
Summary: This study aims to extract the transmission spectrum of the HI Balmer lines of the ultra-hot Jupiter KELT-20b/MASCARA-2b and compare it with the results obtained through forward modeling. Line profiles were extracted from six transits observed with the HARPS-N high-resolution spectrograph. The synthetic transmission spectrum derived from the NLTE TP profile is in good agreement with the observed HI Balmer line profiles, validating the obtained atmospheric structure.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
T. Azevedo Silva, O. D. S. Demangeon, N. C. Santos, R. Allart, F. Borsa, E. Cristo, E. Esparza-Borges, J. Seidel, E. Palle, S. G. Sousa, H. M. Tabernero, M. R. Zapatero Osorio, S. Cristiani, F. Pepe, R. Rebolo, V Adibekyan, Y. Alibert, S. C. C. Barros, F. Bouchy, V Bourrier, G. Lo Curto, P. Di Marcantonio, V D'Odorico, D. Ehrenreich, P. Figueira, J. I. Gonzalez Hernandez, C. Lovis, C. J. A. P. Martins, A. Mehner, G. Micela, P. Molaro, D. Mounzer, N. J. Nunes, A. Sozzetti, A. Suarez Mascareno, S. Udry
Summary: This article investigates the atmospheric compositions and dynamics of two ultra-hot Jupiters, WASP-76b and WASP-121b. By reanalyzing the transit observations, novel species including Ba +, Co, Sr +, and tentative detection of Ti + are discovered, expanding the known atmospheric compositions of these exoplanets.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
H. Gu, J. Cui, D. -D. Niu, X. -S. Wu, F. He, Y. Wei
Summary: The study evaluates the role of chemically induced escape on Triton and identifies dominant processes for various species. Chemical escape rates for H, C, N, and O are calculated, indicating significant contributions to N and O escape on Triton.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
T. Cavalie, B. Benmahi, V. Hue, R. Moreno, E. Lellouch, T. Fouchet, P. Hartogh, L. Rezac, T. K. Greathouse, G. R. Gladstone, J. A. Sinclair, M. Dobrijevic, F. Billebaud, C. Jarchow
Summary: In this study, wind speeds in Jupiter's stratosphere were measured to bridge the altitude gap between the tropospheric and ionospheric wind patterns. Zonal jets were detected at low-to-mid latitudes, while nonzonal winds were found at polar latitudes, potentially aiding in chemical complexification processes.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Briley L. Lewis, John A. Stansberry, Bryan J. Holler, William M. Grundy, Bernard Schmitt, Silvia Protopapa, Carey Lisse, S. Alan Stern, Leslie Young, Harold A. Weaver, Catherine Olkin, Kimberly Ennico
Summary: Researchers used New Horizons LEISA spectral data to map the global distribution of nitrogen ice on Pluto, revealing insights into seasonal processes, energy balance, and nitrogen inventory. They found that a significant fraction of Pluto's nitrogen ice is stored in Sputnik Planitia, and the low emissivity of the nitrogen ice may result in extended periods of constant pressure in Pluto's atmosphere.
Article
Astronomy & Astrophysics
Dale P. Cruikshank, Cristina M. Dalle Ore, Francesca Scipioni, Ross A. Beyer, Oliver L. White, Jeffrey M. Moore, William M. Grundy, Bernard Schmitt, Kirby D. Runyon, James T. Keane, Stuart J. Robbins, S. Alan Stern, Tanguy Bertrand, Chloe B. Beddingfield, Catherine B. Olkin, Leslie A. Young, Harold A. Weaver, Kimberly Ennico
Summary: The prominent fossa trough and adjacent impact crater on Pluto's Viking Terra show evidence of being filled with a material of uniform texture and red-brown color, possibly cryolava. Spectral maps indicate the presence of H2O ice and ammoniated components in these structures, potentially ammonia hydrates or ammoniated salts. The study suggests that the crater and fossa trough were flooded by cryolava from Pluto's interior, which contained liquid water infused with red-brown pigment and ammonia compounds.
Article
Astronomy & Astrophysics
L. R. Gabasova, B. Schmitt, W. Grundy, T. Bertrand, C. B. Olkin, J. R. Spencer, L. A. Young, K. Ennico, H. A. Weaver, S. A. Stern
Summary: In 2015, the New Horizons spacecraft provided detailed measurements of the surface properties of the Pluto system, leading to the creation of global reflectance, topography, and multispectral surface maps. By analyzing high-resolution hyperspectral data, qualitative composition maps for CH4, N-2, H2O ice, and a tholin-like red material were generated. These maps were compared with existing ones and used to study the global distribution of surface components.
Article
Astronomy & Astrophysics
Perianne E. Johnson, Leslie A. Young, Silvia Protopapa, Bernard Schmitt, Leila R. Gabasova, Briley L. Lewis, John A. Stansberry, Kathy E. Mandt, Oliver L. White
Summary: Pluto's heterogeneous surface may be the result of atmospheric pressure variations interrupting haze production and deposition. By modeling the relationship between surface pressure and N-2 ice distribution, we can determine when haze production is disrupted.
Article
Astronomy & Astrophysics
C. M. Lisse, L. A. Young, D. P. Cruikshank, S. A. Sandford, B. Schmitt, S. A. Stern, H. A. Weaver, O. Umurhan, Y. J. Pendleton, J. T. Keane, G. R. Gladstone, J. M. Parker, R. P. Binzel, A. M. Earle, M. Horanyi, M. R. El-Maarry, A. F. Cheng, J. M. Moore, W. B. McKinnon, W. M. Grundy, J. J. Kavelaars, I. R. Linscott, W. Lyra, B. L. Lewis, D. T. Britt, J. R. Spencer, C. B. Olkin, R. L. McNutt, H. A. Elliott, N. Dello-Russo, J. K. Steckloff, M. Neveu, O. Mousis
Summary: This paper discusses the long-term nature of stable majority ices in Kuiper Belt object MU69, finding that HCN, CH3OH, and H2O ices are the most refractory. It predicts future detection of HCN or poly-H2CO based species on MU69's surface. The study also suggests that methanol ice may be ubiquitous in the outer solar system and provides insights into the formation era of MU69 and the origins of icy bodies in the solar system.
Article
Astronomy & Astrophysics
Pierre Beck, Jolantha Eschrig, Sandra Potin, Trygve Prestgard, Lydie Bonal, Eric Quirico, Bernard Schmitt
Summary: The study uses laboratory spectra of carbonaceous chondrites to derive the water content in C-type main-belt asteroids. Most C-type asteroids have lower water contents than chondritic meteorites, possibly due to space weathering effects. In addition, an anti-correlation between water content and spectral slope suggests variability in surface hydration may be influenced by surface material composition.
Article
Astronomy & Astrophysics
F. Scipioni, O. White, J. C. Cook, T. Bertrand, D. P. Cruikshank, W. M. Grundy, C. Beddingfield-Cartwright, R. P. Binzel, C. M. Dalle Ore, D. Jennings, J. M. Moore, C. B. Olkin, S. Protopapa, D. C. Reuter, B. Schmitt, K. N. Singer, J. R. Spencer, S. A. Stern, H. A. Weaver, A. J. Verbiscer, L. A. Young
Summary: The study compared spectroscopic data of Sputnik Planitia on Pluto acquired by the New Horizons' LEISA instrument to the geomorphology mapped using LORRI and MVIC imaging. By analyzing the spectral differences and elemental compositions of geological units, the study explored the connections and differences between different terrains and regions.
Article
Astronomy & Astrophysics
Mathilde Faure, Eric Quirico, Alexandre Faure, Philippe Boduch, Hermann Rothard, Emmanuel Balanzat, Donia Baklouti, Rosario Brunetto, Lydie Bonal, Pierre Beck, Bernard Schmitt
Summary: The study questions the radiolytic origin of certain organic matter found in primitive chondrites and on the surface of Trans-Neptunian Objects, minor planets, and icy satellites. While ion irradiation of simple compounds like ices is not viable for synthesizing certain types of organic matter, it is possible to generate polyaromatic materials from aromatic-rich precursors.
Article
Geochemistry & Geophysics
J. D. Campbell, B. Schmitt, O. Brissaud, J-P Muller
Summary: Laboratory experiments were conducted to generate a diagnostic spectrum for polycyclic aromatic hydrocarbons (PAHs) in the context of the Martian South Polar Residual Cap (SPRC) and to improve the detectability of PAH spectral features in CO2 ice. The study aims to provide data to enhance the interpretation of orbital remote sensing spectroscopic imaging data and records a detectability limit for observing PAHs in CO2 ice with new spectral features revealed between 0.7 and 1.1 μm.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Astronomy & Astrophysics
M. Fayolle, E. Quirico, B. Schmitt, L. Jovanovic, T. Gautier, N. Carrasco, W. Grundy, V. Vuitton, O. Poch, S. Protopapa, L. Young, D. Cruikshank, C. Dalle Ore, T. Bertrand, A. Stern
Summary: The study compares the aerosol data detected by New Horizons spacecraft with laboratory reflectance measurements of Pluto analogues, investigating the optical properties of aerosols. The results show that some Pluto analogues can reasonably reproduce the photometric level in the near-infrared, but inconsistencies still exist in the red visible slope.
Article
Geochemistry & Geophysics
Katrin Stephan, Mauro Ciarniello, Olivier Poch, Bernard Schmitt, David Haack, Andrea Raponi
Summary: Laboratory measurements were conducted to study the spectral signature of H2O ice, analyzing samples with different particle sizes, mixtures, and shapes at varying temperatures. Temperature changes significantly affect the H2O-ice absorptions and Fresnel reflection peaks, while large particles may cause saturation effects on some spectral parameters. The collected spectra provide a useful spectral library for future investigations of icy satellites like Ganymede and Callisto, key targets of ESA's JUICE mission.
Article
Geochemistry & Geophysics
Mauro Ciarniello, Lyuba V. Moroz, Olivier Poch, Vassilissa Vinogradoff, Pierre Beck, Batiste Rousseau, Istiqomah Istiqomah, Robin Sultana, Andrea Raponi, Gianrico Filacchione, David Kappel, Antoine Pommerol, Stefan E. Schroeder, Cedric Pilorget, Eric Quirico, Vito Mennella, Bernard Schmitt
Summary: This study investigates the spectral effects of water ice, organics, and iron sulphide mixtures through laboratory reflectance spectra, showing significant results on mixing ratios, grain sizes, and mixing modalities. Minor amounts of organics like kerite may remain undetectable in coarse-grained water ice, and the relationship between visible reflectance and water ice abundance is not linear, better indicated by spectral features. Simulation of mixtures using the Hapke model suggests that assumptions on grain size distribution and shape can lead to inaccuracies in estimated mixing ratios.
Article
Multidisciplinary Sciences
Kelsi N. Singer, Oliver L. White, Bernard Schmitt, Erika L. Rader, Silvia Protopapa, William M. Grundy, Dale P. Cruikshank, Tanguy Bertrand, Paul M. Schenk, William B. McKinnon, S. Alan Stern, Rajani D. Dhingra, Kirby D. Runyon, Ross A. Beyer, Veronica J. Bray, Cristina Dalle Ore, John R. Spencer, Jeffrey M. Moore, Francis Nimmo, James T. Keane, Leslie A. Young, Catherine B. Olkin, Tod R. Lauer, Harold A. Weaver, Kimberly Ennico-Smith
Summary: The New Horizons spacecraft returned images and data showing that Pluto's terrains have diverse ages, ranging from ancient to very young. One region stands out with very few impact craters and is dominated by huge rises with hummocky flanks. It is believed that this terrain was resurfaced by cryovolcanic processes, which are unique to Pluto and suggest unexpected, active geology in Pluto's history.
NATURE COMMUNICATIONS
(2022)
Article
Humanities, Multidisciplinary
Bernard Schmitt, Zahira Souidi, Frederique Duquesnoy, Frederic-Victor Donze
Summary: This study tests the use of HyperSpectral Imaging (HSI) in analyzing Neolithic rock paintings and compares it to standard RGB cameras. The results show that HSI can reveal new figures by extracting different pigment types with greater contrast and utilizing the information in the very near infrared part of the spectrum. This non-invasive and efficient methodology has the potential to uncover disappeared paintings and study image juxtapositions and painted layer superimpositions.
Article
Astronomy & Astrophysics
C. M. Lisse, G. R. Gladstone, L. A. Young, D. P. Cruikshank, S. A. Sandford, B. Schmitt, S. A. Stern, H. A. Weaver, O. Umurhan, Y. J. Pendleton, J. T. Keane, J. M. Parker, R. P. Binzel, A. M. Earle, M. Horanyi, M. El-Maarry, A. F. Cheng, J. M. Moore, W. B. McKinnon, W. M. Grundy, J. J. Kavelaars, I. R. Linscott, W. Lyra, B. L. Lewis, D. T. Britt, J. R. Spencer, C. B. Olkin, R. L. McNutt, H. A. Elliott, N. Dello-Russo, J. K. Steckloff, M. Neveu, O. Mousis
Summary: This study presents predictions about the rarity of majority hypervolatile ices in Kuiper Belt objects and Oort Cloud comets, based on new ice species-specific data. These predictions have important implications for the study of the Oort Cloud, including the determination of first objects emplaced into the Oort Cloud, the measurement of gas abundance ratios in the protoplanetary disk, and statistical constraints on the emplacement of objects into the Oort Cloud.
PLANETARY SCIENCE JOURNAL
(2022)