Article
Astronomy & Astrophysics
Norbert Schorghofer
Summary: Caves on Mars may contain water ice deposits, with hoarfrost being the main type of cave ice. The role of cave microclimates in maintaining ice bodies is comparatively evaluated.
Article
Astronomy & Astrophysics
Shannon M. Hibbard, Nathan R. Williams, Matthew P. Golombek, Gordon R. Osinski, Etienne Godin
Summary: Viscous flow features, including lobate debris aprons and lineated valley fill, are common ice-related features found across the mid-latitudes of Mars. The sinuous and lobate features in Arcadia Planitia are believed to be buried debris-covered glaciers formed during higher obliquity periods in Mars' recent past. These features appear to be channelized ice that once flowed but currently reside in a flat-lying region.
Article
Astronomy & Astrophysics
David Fisher, Denis Lacelle, Wayne Pollard
Summary: We can redistribute ground ice in Martian regolith by using freezing point depressing magnesium and calcium perchlorates, which is achieved through the migration of residual liquid water following the initial deposition of ground ice. This migration is driven by forces generated by periodic surface temperatures and the geothermal vertical temperature gradient. Silt and clay rich regoliths behave differently in this process, with silt exhibiting significantly higher water speeds compared to clay.
Article
Astronomy & Astrophysics
Mara Mantegazza, Mauro G. Spagnuolo, Angelo P. Rossi
Summary: This study analyzes pit craters in the north-eastern external slope of Hale Crater, and classifies and analyzes the landforms associated with these craters. The findings suggest that the pit craters might be related to volatile processes and formed by the sublimation/melting of ground ice in glacial or periglacial conditions.
Article
Astronomy & Astrophysics
P. C. Thomas, W. M. Calvin, B. Cantor
Summary: The study investigates the formation time of features in the residual south polar cap of Mars and finds that they mainly concentrate in Mars Years 11-13. The study also reveals the significant role of dust events in the formation.
Article
Geochemistry & Geophysics
David M. H. Baker, Lynn M. M. Carter
Summary: By using SHAllow RADar (SHARAD) radar sounding data, researchers have studied a widespread Middle Amazonian mantle unit on Mars and found significant variations in the physical properties of these mantling units, including ice content and age. The study also reveals the relationship between mantle deposits and glacial basal reflectors in the mid-latitudes of Mars. This research demonstrates the high variability in the origins and evolution of mid-latitude mantling units on Mars.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Astronomy & Astrophysics
M. S. Fernanders, R. Gough, V. F. Chevrier, Z. R. Schiffman, S. B. Ushijima, G. M. Martinez, E. G. Rivera-Valentin, P. D. Archer, J. Clark, B. Sutter, M. A. Tolbert
Summary: Chlorine in various forms is widespread on Mars, with perchlorates and chlorides being commonly found. While perchlorates have been extensively studied, chlorate salts have received less attention. Laboratory studies revealed differences in water uptake behavior between sodium chlorate and magnesium chlorate salts at different temperatures, suggesting temperature-dependent deliquescence properties. Observations also showed the potential interaction of magnesium chlorate with water vapor under specific environmental conditions.
Article
Astronomy & Astrophysics
Daniel C. Berman, Frank C. Chuang, Isaac B. Smith, David A. Crown
Summary: The mapping of Viscous Flow Features (VFFs) in the southern hemisphere of Mars, particularly in the Nereidum Montes region, reveals a dense concentration of well-preserved VFFs and ice-rich mantling deposits. These features likely formed several to tens of millions of years ago during periods of high obliquity in the Late Amazonian Epoch. This region contains a more diverse and complete preservation of VFFs compared to other areas on Mars, providing valuable insights into the formation and evolution of ice-rich landforms in mid-latitude regions.
Article
Astronomy & Astrophysics
Stefano Nerozzi, Maya R. Ortiz, John W. Holt
Summary: The basal unit in the Planum Boreum of Mars is a sedimentary deposit containing water ice and lithic fines. It can be divided into two subunits, rupe over bars and cavi, based on their stratigraphy and age. Despite recent studies, key questions about its nature, age, and historical record remain unanswered.
Article
Meteorology & Atmospheric Sciences
Spencer A. Hill, Natalie J. Burls, Alexey Fedorov, Timothy M. Merlis
Summary: Increasing atmospheric CO2 concentration leads to surface temperature warming. The warming is generally amplified in the Arctic compared to the Antarctic. However, the symmetric component of global-mean-normalized, zonal-mean warming weakly amplifies in the Arctic over time, while the antisymmetric component weakens in all models. The study also found that the symmetric component is more sensitive to the symmetric components of radiative feedback parameter and ocean heat uptake.
JOURNAL OF CLIMATE
(2022)
Article
Geochemistry & Geophysics
P. B. Buhler, S. Piqueux
Summary: Researchers have successfully calculated the adsorptive capacity of Martian regolith and the total mass of its exchangeable CO2 by analyzing the recently discovered South Polar Massive CO2 Ice Deposit. The study shows the existence of a mobile CO2 inventory on obliquity timescales.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Editorial Material
Geosciences, Multidisciplinary
Dustin M. Schroeder, Gregor Steinbrugge
Summary: Bright radar reflections beneath Mars' south polar ice cap initially suggested the presence of liquid water. However, recent research indicates that similar reflections are widespread and other materials may also produce the bright signals, raising the possibility of alternative sources for the observations.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Physics, Multidisciplinary
F. J. T. Salazar, A. F. B. A. Prado
Summary: This study proposes a geoengineering strategy to attenuate solar insolation and offset global warming impacts at the polar regions by constructing a sun-pointing vertical earth ring composed of dust grains. The results show that the attenuation of solar isolation at the polar regions is about twice that of the rest of the Earth.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Geochemistry & Geophysics
E. Vos, O. Aharonson, N. Schorghofer, F. Forget, E. Millour, L. Rossi, M. Vals, F. Montmessin
Summary: The exposed scarps and ice-penetrating radar measurements in the North Polar Layered Deposits (NPLD) of Mars provide valuable information about past climate oscillations, which are believed to be influenced by orbital variations similar to Milankovitch cycles on Earth. A global climate model is used to study the paleoclimate states and better interpret the physical and chemical stratigraphy of the NPLD. The research shows that ice migration from the tropics to the poles occurs in two stages, with the availability of tropical ice significantly affecting the polar accumulation rate.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2022)
Article
Astronomy & Astrophysics
H. Savijarvi, A-M Harri
Summary: Observations from Phoenix and Curiosity show diurnal adsorption of near-surface air moisture, which is insensitive to the mineralogy of regolith. Standard-form adsorption isotherms with different specific surface areas produce nearly identical matches with observed water vapor pressures, suggesting low-pressure water vapor adsorption to martian regolith is nonspecific and associated with low enthalpy.
Article
Geography, Physical
Michael R. Prior-Jones, Elizabeth A. Bagshaw, Jonathan Lees, Lindsay Clare, Stephen Burrow, Mauro A. Werder, Nanna B. Karlsson, Dorthe Dahl-Jensen, Thomas R. Chudley, Poul Christoffersen, Jemma L. Wadham, Samuel H. Doyle, Bryn Hubbard
Summary: Cryoegg is a spherical probe that can be deployed into subglacial hydrological systems to measure temperature, pressure, and electrical conductivity and return data wirelessly. It has demonstrated utility in englacial channels and moulins, with significant data transmission performance in cold ice.
JOURNAL OF GLACIOLOGY
(2021)
Article
Multidisciplinary Sciences
Robert Law, Poul Christoffersen, Bryn Hubbard, Samuel H. Doyle, Thomas R. Chudley, Charlotte M. Schoonman, Marion Bougamont, Bas des Tombe, Bart Schilperoort, Cedric Kechavarzi, Adam Booth, Tun Jan Young
Summary: Measurements of ice temperature are crucial for understanding ice viscosity and thermodynamic processes within glaciers. Researchers advanced their understanding of glacier thermodynamics by obtaining a high-vertical-resolution temperature-sensing profile from a deep borehole in Greenland. The findings reveal notable spatial heterogeneity in conditions facilitating the fast motion of marine-terminating glaciers in Greenland, both vertically and at the catchment scale.
Article
Geography, Physical
Samuel H. Doyle, Bryn Hubbard, Poul Christoffersen, Robert Law, Duncan R. Hewitt, Jerome A. Neufeld, Charlotte M. Schoonman, Thomas R. Chudley, Marion Bougamont
Summary: This study reports detailed measurements of subglacial water pressure response to drilling and connecting adjacent water-filled boreholes through kilometre-thick ice in Greenland. The measurements provide evidence for gap opening at the ice-sediment interface and stress transfer affecting water pressure in hydraulically-isolated cavities. The study suggests that opening gaps at the ice-sediment interface and subsequent changes in hydraulic conductivity deserve further attention.
JOURNAL OF GLACIOLOGY
(2022)
Article
Multidisciplinary Sciences
Tun Jan Young, Poul Christoffersen, Marion Bougamont, Slawek M. Tulaczyk, Bryn Hubbard, Kenneth D. Mankoff, Keith W. Nicholls, Craig L. Stewart
Summary: Subglacial hydrologic systems play a key role in regulating ice sheet flow. This study reveals the presence of basal melt and unexpectedly warm subglacial conditions beneath a large Greenlandic outlet glacier. These findings have implications for understanding and modeling ice sheet behavior.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Geosciences, Multidisciplinary
Josephine Hornsey, Ann Rowan, Martin P. Kirkbride, Stephen J. Livingstone, Derek Fabel, Angel Rodes, Duncan J. Quincey, Bryn Hubbard, Vincent Jomelli
Summary: Observations of glacier behavior in the Everest region of Nepal revealed seven glacial stages in the Holocene period, which correlate with similar stages in the monsoon-influenced Himalaya region, demonstrating a coherent record of high elevation terrestrial palaeoclimate change that can be extracted from dynamic mountain landscapes.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Geography, Physical
Jayne E. E. Kamintzis, Tristram D. L. Irvine-Fynn, Tom O. O. Holt, John P. P. Jones, Philip R. R. Porter, Stephen J. A. Jennings, Kathrin Naegeli, Bryn Hubbard
Summary: Meltwater routing through ice masses plays a fundamental role in regulating glacier dynamics, mass balance, and proglacial hydrology. However, direct observations of englacial channels and their flow conditions remain limited. In this study, terrestrial laser scanning (TLS) surveys were conducted on the main englacial channel of cold-based Austre Broggerbreen in Svalbard. The results reveal spatial variations in water flow conditions, channel incision mechanisms, and the presence of different hydrological conditions.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
Katie E. E. Miles, Bryn Hubbard, Evan S. S. Miles, Duncan J. J. Quincey, Ann V. V. Rowan
Summary: The study focuses on the internal structure of a debris-covered glacier in the Himalayas using high-resolution optical televiewer (OPTV) logs. The logs reveal thin structural features that are up to an order of magnitude thinner than those observed on the glacier surface. Five structural units were identified, including primary stratification, debris-rich planes, water-healed crevasse traces, healed crevasse traces, and steeply dipping planes of basally derived sediment near the glacier terminus. The logs also show that the primary stratification decreases and rotates with depth, indicating a previously more dynamic glacier regime.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geography, Physical
Emma Pearce, Adam D. D. Booth, Sebastian Rost, Paul Sava, Tugrul Konuk, Alex Brisbourne, Bryn Hubbard, Ian Jones
Summary: The density structure of firn plays a crucial role in hydrological and climate modelling, as well as ice-shelf stability. Traditional methods like Herglotz-Wiechert inversion (HWI) can evaluate firn structure by analyzing depth models of seismic velocity. However, these methods are only suitable for steady-state firn profiles and may encounter difficulties when there are ice layers present. Full waveform inversion (FWI) overcomes these limitations and shows better performance in detecting ice slab boundaries and velocity anomalies within firn.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geography, Physical
Katie E. Miles, Bryn Hubbard, Evan S. Miles, Duncan J. Quincey, Ann V. Rowan
Summary: The debris on high-elevation debris-covered glaciers plays a significant role in shaping their features and processes. However, our understanding of the subsurface environments of these glaciers is still very limited. More field-based studies are needed to improve numerical models and enhance predictions.
ANNALS OF GLACIOLOGY
(2023)
Article
Geography, Physical
Emma Pearce, Adam D. Booth, Sebastian Rost, Paul Sava, Tugrul Konuk, Alex Brisbourne, Bryn Hubbard, Ian Jones
Summary: The density structure of firn is important for hydrological and climate modelling, as well as ice shelf stability. The use of Full Waveform Inversion (FWI) instead of Herglotz-Wiechert inversion (HWI) can provide a more accurate assessment of firn structure, especially in cases with ice layers.
ANNALS OF GLACIOLOGY
(2023)
Article
Geography, Physical
Adam D. D. Booth, Poul Christoffersen, Andrew Pretorius, Joseph Chapman, Bryn Hubbard, Emma C. C. Smith, Sjoerd de Ridder, Andy Nowacki, Bradley Paul Lipovsky, Marine Denolle
Summary: Distributed Acoustic Sensing (DAS) is a valuable tool for glaciological seismic applications, but analyzing the large data volumes generated poses computational challenges. Active-source DAS has the potential to image and characterize subglacial sediment, but the lack of subglacial velocity constraint limits accuracy. Compression using the frequency-wavenumber (f-k) transform and a convolutional neural network provides a significant improvement in efficiency for analyzing cryoseismic events. Combining active and passive-source data with machine learning frameworks unlocks the potential of large DAS datasets for future applications.
ANNALS OF GLACIOLOGY
(2023)
Article
Geography, Physical
Martin P. P. Kirkbride, Sophie C. C. Sherriff, Ann V. V. Rowan, David L. L. Egholm, Duncan J. J. Quincey, Evan Miles, Bryn Hubbard, Katie Miles
Summary: The origin of debris covers on high-elevation compound valley glaciers is influenced by melt-out of englacial debris and changing tributary supply. Geochemical analysis of debris samples from Khumbu Glacier in Nepal reveals differences in debris sources related to lithological variations. The dominance of ice sources has shifted from lower elevation tributaries to higher elevation catchments over time, indicating changes in the glacier's structure.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geography, Physical
Matt Jenkin, Margaux Hofmann, Bryn Hubbard, Davide Mancini, Floreana M. Miesen, Frederic Herman, Stuart N. Lane
Summary: This study presents a method for tracking radio-tagged pebbles and cobbles in subglacial meltwater channels under shallow temperate glaciers. The method uses a roving antenna to localize tagged particles planimetrically and a stationary antenna to monitor the timing of particle transport events. The records from both antennas are combined to create a model for particle transport distance. This method provides valuable insights into the mechanisms and timescales of sediment export from Alpine glaciers.
JOURNAL OF GLACIOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Bryn Hubbard, Poul Christoffersen, Samuel H. Doyle, Thomas R. Chudley, Charlotte M. Schoonman, Robert Law, Marion Bougamont
Summary: The optical televiewer borehole logging in a crevassed region of Store Glacier, Greenland, revealed high-angle planes of refrozen ice layers that are likely traces of former open crevasses. These crevasse traces decrease in frequency with depth and show a consistent orientation with a dip of 63 degrees and a strike offset by 71 degrees. These traces represent planes of weakness that may have originated upglacier and are likely to survive surface ablation to reach the glacier terminus.
Article
Environmental Sciences
Katie E. Miles, Bryn Hubbard, Evan S. Miles, Duncan J. Quincey, Ann V. Rowan, Martin Kirkbride, Josephine Hornsey
Summary: Surface melting of High Mountain Asian debris-covered glaciers significantly affects the seasonal water supply to millions of people, with the thickness of the supraglacial debris layer playing a key role. Research on the debris-covered Khumbu Glacier in Nepal shows that englacial debris concentrations are higher near the glacier terminus compared to the mid-to-upper ablation area, complicating predictions of future rates of surface melt and debris exhumation.
COMMUNICATIONS EARTH & ENVIRONMENT
(2021)
Article
Astronomy & Astrophysics
Maria Angeles Lopez-Cayuela, Maria-Paz Zorzano, Juan Luis Guerrero-Rascado, Carmen Cordoba-Jabonero
Summary: The atmospheric dust cycle on Mars plays a dominant role in the planetary radiative balance, atmospheric photochemistry escape, and redistribution of materials on the surface. A methodology is presented to accurately describe the annual dust redistribution cycle on Mars using orbital global and seasonal measurements of atmospheric dust opacity. The analysis shows that approximately 4 trillion kilograms of dust is transported globally in the atmosphere during a typical Mars year.
Article
Astronomy & Astrophysics
Audrey Vorburger, Shahab Fatemi, Shane R. Carberry Mogan, Andre Galli, Lucas Liuzzo, Andrew R. Poppe, Lorenz Roth, Peter Wurz
Summary: The study presents new model results for the composition of Ganymede's atmosphere, finding that sublimation remains the major source process for H2O, while radiolysis induced by auroral electrons dominates the source fluxes for O2 and H2.
Article
Astronomy & Astrophysics
Qi He, Zhi Cao, Yuqi Qian, Hejiu Hui, Ioannis Baziotis, Long Xiao, Zaicong Wang, Biji Luo, Yiheng Li, Zongjun Ying, Yang Li
Summary: The Chang'e-5 mission collected lunar soil containing magnesian troctolitic granulites, which provide valuable information on the composition of the lunar crust. Through analysis and modeling, it is suggested that these granulites may have originated from the Pythagoras crater and were transported to the landing site.
Article
Astronomy & Astrophysics
Jordan M. Bretzfelder, Kathryn M. Stack, Abigail A. Fraeman, Mackenzie Day, William E. Dietrich, Alexander B. Bryk
Summary: This study investigates the development of bedrock ridges on Mars and their implications for wind history, deposition, and erosion in Gale crater.
Article
Astronomy & Astrophysics
Lot Ram, Diptiranjan Rout, Rahul Rathi, Paul Withers, Sumanta Sarkhel
Summary: This study investigates the impacts of interplanetary coronal mass ejections (ICMEs) on the Martian ionosphere, specifically the behavior of the ionospheric peak density and height during ICME passages. The study used observations from the Radio Occultation Science Experiment (ROSE) aboard the MAVEN spacecraft and selected 8 ICMEs from existing catalogs. The results show that ICMEs lead to an elevation of the ionospheric peak height and a decrease in peak density, and propose that vertical pressure gradient and electron temperature enhancement are plausible causes for ionospheric variability.
Article
Astronomy & Astrophysics
Benoit Jabaud, Riccardo Artoni, Gabriel Tobie, Erwan Le Menn, Patrick Richard
Summary: The Cassini spacecraft discovered active jets of water vapour and ice grains at the South Pole of Enceladus, resulting in the deposit of freshly erupted materials on the moon's icy surface. Similar processes may be happening on Europa as well. Determining the mechanical properties of fresh icy powder-like materials is essential for future landing and sampling missions. The flowability and surface energy of ice powders decrease with increasing temperatures, which may have implications for stable landing and the flow of ice materials on Enceladus and Europa.
Article
Astronomy & Astrophysics
Lydie Bonal, Eric Quirico, Gilles Montagnac, Mutsumi Komatsu, Yoko Kebukawa, Hikaru Yabuta, Kana Amano, Jens Barosch, Laure Bejach, George D. Cody, Emmanuel Dartois, Alexandre Dazzi, Bradley De Gregorio, Ariane Deniset-Besseau, Jean Duprat, Cecile Engrand, Minako Hashiguchi, Kanami Kamide, David Kilcoyne, Zita Martins, Jeremie Mathurin, Smail Mostefaoui, Larry Nittler, Takuji Ohigashi, Taiga Okumura, Laurent Remusat, Scott Sandford, Miho Shigenaka, Rhonda Stroud, Hiroki Suga, Yoshio Takahashi, Yasuo Takeichi, Yusuke Tamenori, Maximilien Verdier-Paoletti, Shohei Yamashita, Tomoki Nakamura, Hiroshi Naraoka, Takaaki Noguchi, Ryuji Okazaki, Hisayoshi Yurimoto, Shogo Tachibana, Masanao Abe, Akiko Miyazaki, Aiko Nakato, Satoru Nakazawa, Masahiro Nishimura, Tatsuaki Okada, Takanao Saiki, Kanako Sakamoto, Satoshi Tanaka, Fuyuto Terui, Yuichi Tsuda, Tomohiro Usui, Sei-ichiro Watanabe, Toru Yada, Kasumi Yogata, Makota Yoshikawa
Summary: This paper focuses on characterizing the thermal history of asteroid Ryugu by studying the structure of polyaromatic carbonaceous matter in the returned samples. The study finds that there is no structural difference in the polyaromatic component between the two sampling sites on Ryugu, indicating that the thermal metamorphism related to radioactive decay was not significant. However, some structural variability is observed within the particle set.
Article
Astronomy & Astrophysics
M. Luginin, A. Fedorova, D. Belyaev, F. Montmessin, O. Korablev, J. -l. Bertaux
Summary: Spectroscopic solar occultation measurements by the SPICAV/SOIR instrument onboard the Venus Express orbiter provided new data on the upper haze aerosol properties, its distribution, and variations. A joint analysis of data from two spectrometers revealed a bimodal distribution in about 50% of observations previously believed to be unimodal, and characterized the size distribution 10 km higher in the atmosphere compared to previous analysis.
Article
Astronomy & Astrophysics
A. Mahieux, S. Viscardy, K. L. Jessup, F. P. Mills, L. Trompet, S. Robert, S. Aoki, A. Piccialli, A. C. Vandaele
Summary: We report on the mean upper limit number densities and volume concentrations of H2CO, O-3, NH3, HCN, N2O, NO2, NO, and HO2 at the Venus terminator above the cloud layer. Attempts to detect these species using a statistical algorithm and the method presented by Trompet et al. (2021) were unsuccessful, and upper limits of detection are provided.
Article
Astronomy & Astrophysics
P. M. Streeter, S. R. Lewis, M. R. Patel, J. A. Holmes, K. Rajendran
Summary: The northern polar vortex on Mars shows a high degree of interannual repeatability in its structure and evolution, except during large dust storms. The seasonal timing of these storms seems to be the key factor determining their impacts on the polar vortex.
Article
Astronomy & Astrophysics
Michael T. Mellon, Hanna G. Sizemore, Jennifer L. Heldmann, Christopher P. McKay, Carol R. Stoker
Summary: The search for life is a major focus of Mars exploration, with temperature and water activity being key factors for habitability. The most recent habitable conditions occurred about 510 kyrs ago and lasted for about 10s of kyrs each occurrence. All latitudes offer potential for life exploration, but middle-latitude sites have access to 100-kyr-old ice that experienced past habitable conditions, while high-latitude sites offer access to ancient ice over 1 Myrs old.
Article
Astronomy & Astrophysics
Anthony Ozerov, Jeffrey C. Smith, Jessie L. Dotson, Randolph S. Longenbaugh, Robert L. Morris
Summary: The Geostationary Lightning Mapper (GLM) instruments, with their large combined field of view, are useful for studying the population of atmospheric phenomena like bolides. However, there are biases when using GLM for non-lightning purposes, which need to be studied and accounted for before precise measurements of bolide flux can be obtained. A Bayesian Poisson regression model was developed to estimate instrumental biases and the latitudinal variation of bolide flux concurrently. The estimated bias corresponds to the known sensitivity of the GLM instruments, and the latitudinal flux variation estimates are consistent with a strong bias towards high-velocity bolides, as compared to existing theoretical models.
Article
Astronomy & Astrophysics
P. Beck, P. Y. Meslin, A. Fau, O. Forni, O. Gasnault, J. Lasue, A. Cousin, S. Schroeder, S. Maurice, W. Rapin, R. C. Wiens, A. M. Ollila, E. Dehouck, N. Mangold, B. Garcia, S. Schwartz, W. Goetz, N. Lanza
Summary: Analysis of data obtained by ChemCam on Mars reveals that the carbon signal is mainly related to ionization of the atmosphere, with variability potentially linked to the physical state of the atmosphere. Up to sol 3355, no carbonate was detected in the ChemCam dataset, suggesting that it is not a major constituent (>50%) in the analyzed targets and that carbon in soils is not enriched beyond the limit of detection. The dominant salts found in Gale are sulfate and chlorides, while the absence of carbonates, seen in Jezero, may be due to differences in protolith.
Article
Astronomy & Astrophysics
Eloy Pena-Asensio, Jaakko Visuri, Josep M. Trigo-Rodriguez, Hector Socas-Navarro, Maria Gritsevich, Markku Siljama, Albert Rimola
Summary: The observation of interstellar objects 1I/'Oumuamua and 2I/Borisov suggests the existence of a larger population of smaller projectiles that impact our planet with unbound orbits. A statistical evaluation of uncertainties in the CNEOS database and study of its hyperbolic fireballs reveals an anisotropic geocentric radiant distribution and low orbital inclinations, challenging the assumption of a randomly incoming interstellar population. These findings suggest that apparent interstellar meteors may, in fact, be the result of accelerated meteoroid impacts caused by close encounters with massive objects within or passing through our solar system.
Article
Astronomy & Astrophysics
Cecilia W. S. Leung, Leslie K. Tamppari, David M. Kass, German Martinez, Erik Fischer, Michael D. Smith
Summary: Using a combination of orbital and surface observations, this study investigates the vertical distribution of water vapor in the lower atmospheres of Mars. The findings suggest that the assumption of uniformly mixed water vapor in the boundary layer is not always consistent with observational constraints. The results provide important insights into the seasonal transport of water and the role of regolith-atmospheric exchange.