Article
Astronomy & Astrophysics
A. B. Cunje, A. J. Dombard, R. R. Ghent
Summary: Larger impact craters and basins on the Moon show a discrepancy in crater size frequency distributions between their interior melt surfaces and exterior ejecta blankets. Despite elevated thermal conditions favorable to relaxation, simulations suggest that other mechanisms are likely responsible for the discrepancy in ages between the melt and ejecta surfaces.
Article
Astronomy & Astrophysics
Yanxia Tan, Yuji Harada
Summary: This paper investigates the effect of the low-viscosity zone in the deep interior of the Moon on tidal response through hypothetical temperature profiles. Numerical computations of tidal parameters show dependence on the low-viscosity zone and frequency, with the tidal quality factor and tidal Love numbers being key parameters. The study suggests a viscosity solution for the middle layer and an outer radius for the low-viscosity zone based on observational ranges of frequency-dependent quality factors and Love numbers.
Article
Astronomy & Astrophysics
Lynnae C. Quick, Sarah A. Fagents, Karla A. Nunez, Kierra A. Wilk, Ross A. Beyer, Chloe B. Beddingfield, Emily S. Martin, Louise M. Prockter, Terry A. Hurford
Summary: By modeling the formation of cryolava domes on Europa, this study suggests that these domes may have been formed by viscous fluids composed of a mixture of water, salts, and ice crystals. The rheology of these cryolavas is more similar to basalt than to typical dome-forming lavas on Earth. Some of these domes may be connected to liquid reservoirs in Europa's crust, indicating ongoing subsurface-surface exchange.
Article
Astronomy & Astrophysics
Takeshi Tsuji, Taizo Kobayashi, Junji Kinoshita, Tatsunori Ikeda, Tomoki Uchigaki, Yuichiro Nagata, Taichi Kawamura, Kazunori Ogawa, Satoshi Tanaka, Akito Araya
Summary: We have developed a lunar active seismic profiler (LASP) that integrates active seismic sources and receivers on a rover. By processing LASP data, we obtained accurate S-wave velocity profiles and were able to identify subsurface ice and geological boundaries. Field experiments demonstrated that LASP can support 3D velocity distribution estimates and the exploration of deeper substrates.
Article
Geochemistry & Geophysics
M. S. Huber, E. Kovaleva, A. S. P. Rae, N. Tisato, S. P. S. Gulick
Summary: The research examines the preservation potential of deeply eroded impact structures by comparing the Vredefort and Chicxulub impact structures. It finds that the Vredefort target rocks do not show measurable changes in physical properties and the gravity signature of the impact structure is minor. The study suggests that the identification of ancient impact structures is limited by the lack of geophysical signatures associated with deeply eroded craters.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Environmental Sciences
Jiayin Deng, Weiming Cheng, Yimeng Jiao
Summary: This research studied the diversity in the geological evolution of three impact basins on the lunar surface using topography, geomorphology, chemical composition, mineralogical composition, lunar crust thickness, and subsurface structures analyses. The results showed that the basins have cavity-like shapes with variations in crustal thickness and uplift of the crust-mantle interface. Collapses occurred at the crust-mantle interface in the mare regions of two basins. The chemical and mineral compositions of both basin and mare formations exhibited bimodal distributions, and olivine-rich materials were found in specific locations.
Article
Astronomy & Astrophysics
Harry A. Ballantyne, Martin Jutzi, Gregor J. Golabek, Lokesh Mishra, Kar Wai Cheng, Antoine B. Rozel, Paul J. Tackley
Summary: A giant impact is suggested as the explanation for the Martian Dichotomy, with recent studies favoring a hybrid origin caused by impact-induced crust-production. This study uses a large suite of impact simulations and a sophisticated geophysical scheme to investigate the feasibility of a giant impact on either hemisphere of Mars. The results suggest that a cannonical Borealis-forming impact is not possible, but instead favor an impact and subsequent localised magma ocean in the southern hemisphere that results in a thicker crust than the north.
Article
Astronomy & Astrophysics
N. Thomas
Summary: A comprehensive investigation of Io can provide answers to many mysteries, shed light on landscape-forming processes, and offer insight into the formation processes of Earth, Moon, planets and moons.
EXPERIMENTAL ASTRONOMY
(2022)
Editorial Material
Multidisciplinary Sciences
Shannon Hall
Summary: Geologists were aware of an impending earthquake in southeastern Turkey decades ago, but accurate prediction remains a concept confined to science fiction.
News Item
Multidisciplinary Sciences
Davide Castelvecchi
Summary: Droplets of sodium and potassium donate electrons to make water metallic.
News Item
Multidisciplinary Sciences
Alexandra Witze
Summary: NASA's InSight mission has provided the first data on the internal structure of a planet other than Earth, revealing surprising cake-like layers in the crust of Mars.
Article
Geochemistry & Geophysics
Mariana Martinho, Timothy Tylor-Jones, Leonardo Azevedo
Summary: Seismic inversion is a crucial step in the seismic reservoir characterization workflow, where the choice of method can significantly impact the prediction of spatial distribution of rock properties. The performance of inversion methods is influenced by data quality and research objectives.
GEOPHYSICAL PROSPECTING
(2021)
Article
Multidisciplinary Sciences
Sune G. Nielsen, David V. Bekaert, Maureen Auro
Summary: Isotopic measurements of lunar and terrestrial rocks have shown that the Moon is similar to Earth in terms of isotopic composition, possibly due to isotope fractionation on proto-Earth during terrestrial core formation and a canonical giant impact. The data suggest that the impactor and proto-Earth mainly accreted from a common isotopic reservoir in the inner solar system.
NATURE COMMUNICATIONS
(2021)
Article
Astronomy & Astrophysics
J. A. Kegerreis, S. Ruiz-Bonilla, V. R. Eke, R. J. Massey, T. D. Sandnes, L. F. A. Teodoro
Summary: Traditionally, the Moon is believed to have formed from debris ejected by a giant impact on early Earth. However, the details of the impact scenarios are debated, and models struggle to explain the isotopic compositions of Earth and lunar rocks as well as the system's angular momentum. A high-resolution simulation suggests that giant impacts can place a satellite with similar mass and iron content as the Moon into orbit outside Earth's Roche limit. Even satellites passing within the Roche limit can survive by being partially stripped and torqued onto stable orbits.
ASTROPHYSICAL JOURNAL LETTERS
(2022)
Article
Astronomy & Astrophysics
S. Ruiz-Bonilla, V. R. Eke, J. A. Kegerreis, R. J. Massey, L. F. A. Teodoro
Summary: A study simulated the collision event between proto-Earth and a Mars-sized impactor, resulting in the formation of a Moon-sized self-gravitating clump in the debris disk, with its internal composition being resolved for the first time. The clump mainly consists of impactor material near the core, but becomes enriched in proto-Earth material near the surface. The formation of this Moon-sized clump is found to depend sensitively on the spin of the impactor.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Geochemistry & Geophysics
L. L. Hood, J. S. Oliveira, J. Andrews-Hanna, M. A. Wieczorek, S. T. Stewart
Summary: A recent study on the lunar crustal magnetic field map revealed the presence of internal magnetic anomalies within ringed impact basins, suggesting probable trajectories of impactors and discrepancies in magnetization directions compared to the internal lunar dynamo field.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Geochemistry & Geophysics
David G. Horvath, Jeffrey C. Andrews-Hanna
Summary: The central mound of Gale crater preserves a record of early Martian climatic, hydrologic, and sedimentary history, showing transitions from wetter to drier conditions. The models of the hydrological evolution at the crater provide insights into how the climate at Gale crater evolved. Short-term climate changes are crucial for explaining local variations in facies and mineralogy within the crater.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Geochemistry & Geophysics
Pranabendu Moitra, David G. Horvath, Jeffrey C. Andrews-Hanna
Summary: The study investigated the formation of a potential pyroclastic deposit on Mars, exploring subsurface magmatic processes and the impact-triggered volcanic eruption scenario. Numerical models were used to simulate magma ascent and explosive magma fragmentation, while scaling analysis was employed to assess the seismic energy density associated with impact events triggering volcanic eruptions.
EARTH AND PLANETARY SCIENCE LETTERS
(2021)
Article
Astronomy & Astrophysics
David G. Horvath, Pranabendu Moitra, Christopher W. Hamilton, Robert A. Craddock, Jeffrey C. Andrews-Hanna
Summary: The discovery of a potentially young volcanic deposit on Mars suggests that the planet may still be volcanically active, in line with seismic activity detected by the InSight lander.
Article
Multidisciplinary Sciences
Matt J. Jones, Alexander J. Evans, Brandon C. Johnson, Matthew B. Weller, Jeffrey C. Andrews-Hanna, Sonia M. Tikoo, James T. Keane
Summary: Numerical simulations demonstrate that the mantle convection caused by the South Pole-Aitken impact can explain the existence of the nearside-farside lunar asymmetry.
Article
Astronomy & Astrophysics
Weigang Liang, Jeffrey C. Andrews-Hanna
Summary: The GRAIL mission's lunar gravity data revealed a large set of linear to arcuate gravity anomalies on the Moon, categorized into anomalies bordering the Procellarum KREEP terrane (PKT) region and scattered linear gravity anomalies in the highlands. Analyzing band-passed gravity gradient maps and power spectral analyses helps characterize the nature and differences between these anomalies.
Article
Astronomy & Astrophysics
A. Broquet, J. C. Andrews-Hanna
Summary: This study investigates the tectonic and geophysical features of Hesperia Planum, a volcanic plain covered by wrinkle ridges. The research reveals that the region exhibits a high density of wrinkle ridges and a larger compressional strain compared to typical Hesperian strains. By introducing a loading sequence of crustal loading and volcanism, the study proposes a model to explain the characteristics of Hesperia Planum, including crustal thinning, low relief, and their correlation with wrinkle ridges and magnetic anomalies. The results suggest that scattered mantle plumes may be responsible for the formation of Hesperia Planum and other volcanic provinces within the highlands.
Editorial Material
Astronomy & Astrophysics
Jeffrey C. Andrews-Hanna
Article
Astronomy & Astrophysics
A. Broquet, J. C. Andrews-Hanna
Summary: Although most volcanic and tectonic activity on Mars occurred in its earlier geologic history, recent activity in Elysium Planitia reveals ongoing activity on Mars. Observational evidence and geophysical models show that Elysium Planitia is underlain by an active mantle plume, explaining the regional gravity and topography highs, recent volcanism, tectonic changes, and ongoing seismicity. This active plume is comparable to terrestrial plumes linked to the formation of large igneous provinces.
Article
Astronomy & Astrophysics
J. C. Andrews-Hanna, A. Broquet
Summary: This study analyzes the density and inferred strain of compressional tectonic structures on Mars, indicating a peak in strain during the late Noachian and early Hesperian periods. The lower tectonic strain in the early and middle Noachian suggests incomplete preservation of strain in older surfaces. The abrupt decrease in strain rate after the early Hesperian may be due to changing mantle rheology or the influence of mantle plumes.
Article
Astronomy & Astrophysics
Samantha A. Moruzzi, Walter S. Kiefer, Jeffrey C. Andrews-Hanna
Summary: Radar images from the Magellan mission reveal compressional ridge belts on Venus, including Vedma Dorsa, formed by blind thrust faulting and shallow folding. Our models suggest fault parameters of D-1-2 km, z-10-25 km, and 0-25-30 degrees. The depth of the upper fault tip and the change in dip at depth indicate an intermediate structure between lobate scraps and fold and thrust belts. The estimated heat flux during the formation of Vedma Dorsa is 16-39 mW/m2.
Article
Geochemistry & Geophysics
Evan Bjonnes, Brandon C. Johnson, Jeffrey C. Andrews-Hanna
Summary: Two impact basins on the Moon of similar size, Freundlich-Sharonov and Hertzsprung, have different surface morphologies and subsurface structures. The presence of a bench-like transitional structure in Hertzsprung, unlike the other basins, indicates a different thermal condition during the cratering process. The varying thermal conditions lead to the development of different types of impact basins.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Astronomy & Astrophysics
Samantha A. Moruzzi, Jeffrey C. Andrews-Hanna, Paul Schenk, Brandon C. Johnson
Summary: Pluto's Sputnik basin is a large impact basin in the outer Solar System that resembles basins in the inner Solar System in morphology and scale. It shows similarities to peak-ring structures found in impact basins on terrestrial bodies, suggesting that it may be more analogous to a peak-ring or multiring basin. A comparative analysis with 23 impact basins in the inner Solar System supports this interpretation.
Article
Multidisciplinary Sciences
Matthew A. Siegler, Jianqing Feng, Katelyn Lehman-Franco, Jeffery C. Andrews-Hanna, Rita C. Economos, Michael St Clair, Chase Million, James W. Head, Timothy D. Glotch, Mackenzie N. White
Summary: Microwave-wavelength measurements have shown the existence of a large granitic system below the thorium-rich farside feature on the Moon. This feature has a peak heat flux that is 20 times higher than the average lunar highlands, suggesting the presence of an Earth-like, evolved granitic system larger than previously believed possible on the Moon.
Article
Astronomy & Astrophysics
Jeffrey C. Andrews-Hanna
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.