Article
Astronomy & Astrophysics
Olena Shubina, Valery Kleshchonok, Oleksandra Ivanova, Igor Luk'yanyk, Alexander Baransky
Summary: The analysis of photometrical observations of comet 29P/Schwassmann-Wachmann 1 is presented, based on 15 nights of broadband observations from 2012 to 2019. The apparent magnitudes and dust productivity level Af p in filter R were calculated. Four jet-like structures were detected in the coma on almost all dates, with the nucleus rotation period estimated to be 57 +/- 2 days and the active regions located within a narrow belt near the equator.
Article
Astronomy & Astrophysics
Qasim Afghan, Geraint H. Jones, Oliver Price, Andrew Coates
Summary: Cometary dust tails exhibit various structures, most of which are believed to be caused by factors such as variable dust production and interactions with the solar wind. However, not all of these structures have been fully understood. This study reports the discovery of a peculiar dust tail feature, where a section of the tail is missing. This suggests a temporary decrease in dust production near perihelion.
Article
Astronomy & Astrophysics
Anhelina Voitko, Evgenij Zubko, Oleksandra Ivanova, Igor Luk'yanyk, Anton Kochergin, Marek Husarik, Gorden Videen
Summary: This study measures the photometric color of Comet 29P/Schwassmann-Wachmann 1 and finds variations in color slope, indicating different compositions of particles in the coma. The research also calculates the dustload and dust production rate of the inner coma, which are found to be relatively high compared to other comets.
Article
Astronomy & Astrophysics
Konrad J. Kossacki, Marcin Wesolowski, Grzegorz Skora, Krzysztof Staszkiewicz
Summary: This paper presents the results of experiments on the sliding of desiccated sand on the inclined surfaces of cometary analogs. The experiments were conducted in a vacuum using porous mixtures of water ice and quartz sand. The sliding was only possible when the sand layer as a whole was not fluidized. It was found that the sliding was caused by the rolling or sliding of grains on the surface, rather than the volatility of the underlying water ice.
Article
Astronomy & Astrophysics
Konrad J. Kossacki
Summary: The sublimation of porous water ice in vacuum was investigated in this study. It was found that the surface of porous granular ice can recede much slower than that of compact ice, especially when the porosity is similar to that of comet nuclei. Preliminary experiments at moderate and high temperature gradients were also described.
Article
Astronomy & Astrophysics
Konrad J. Kossacki, Marcin Wesolowski, Slawomira Szutowicz, Tomasz Mikolajkow
Summary: In this work, we experimentally verify different methods for calculating the rate of outgassing of cometary analogues. We investigate new and known formulations for the mass flux of water vapor from mixtures of ice agglomerates. Experiments are performed using samples composed of different ice agglomerates, including both approximately uniform agglomerates and hierarchical structures. The findings suggest that the pressure of vapor between agglomerates is close to phase equilibrium pressure at temperatures above 200 K, and it shows some temperature dependence. We propose suitable functions and present a method for calculating the lifetime of large centimeter-sized porous ice-dust particles in cometary comae.
Article
Astronomy & Astrophysics
Konrad J. Kossacki, Marcin Wesolowski, Slawomira Szutowicz, Tomasz Mikolajkow
Summary: This paper presents experimental studies on the degassing of porous ice and porous mixtures of ice and sand in a vacuum. The relationship between the surface recession rate and the subsurface temperature gradient, as well as the granulation and composition of the material, were investigated. An empirical equation was proposed and tested on samples with a mass fraction of non-volatile material to ice in the range of 0-3.65. Based on the proposed equation, calculations were carried out, which indicate the possibility of landslides on the inclined areas on the surface of comet 9P/Tempel 1.
Article
Astronomy & Astrophysics
M. R. Combi, Y. Shou, T. Makinen, J-L Bertaux, E. Quemerais, S. Ferron, R. Coronel
Summary: The SWAN camera on the SOHO satellite monitors the three-dimensional distribution of solar wind and solar radiation through the imprint on interstellar hydrogen stream, also recording the distribution of hydrogen comae of comets. Analysis of six comets observed by SWAN during 2017-2020 revealed that two of them broke up before perihelion.
Article
Astronomy & Astrophysics
Min Chen, Xianfeng Huang, Jianguo Yan, Zhen Lei, Jean Pierre Barriot
Summary: In this article, we used over 5200 Rosetta/OSIRIS-NAC images to create a high-resolution 3D model of the bilobate comet 67P/Churyumov-Gerasimenko, which is visually more impressive than the existing models. We also measured the volume, mean density, and surface area of the comet, and analyzed the differences between the three models.
Article
Astronomy & Astrophysics
Marcin Wesolowski
Summary: The paper introduces a thermodynamic evolution model of the comet nucleus surface, focusing on the formation of pits. As a result of thermodynamic processes, the surface layer is destroyed, leading to an increase in scattered light area and a sudden increase in brightness.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. Wesolowski
Summary: This paper presents two models to explain the changes in brightness of comets during outbursts. The first model is related to the impact of individual scattering cross-sections on brightness jumps, while the second model is associated with the increase in sublimation active surface. These models suggest that the change in brightness of comets is due to the reduction of surface area caused by water-ice sublimation, leading to a gradual decrease in brightness.
Article
Engineering, Aerospace
Marco Fulle, Dominique Bockelee-Morvan, Fiorangela La Forgia
Summary: The ESA mission Comet Interceptor will target a comet from the Oort Cloud or interstellar space during its first approach to a heliocentric distance of approximately 1 AU. The mission has been designed to handle the maximum dust loss rate observed from comet 1P/Halley as an upper limit. The activity level beyond 3.8 AU depends on the surface area of water-poor pebbles, while within 3.8 AU it depends on the surface area of water-rich pebbles.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Astronomy & Astrophysics
Bjorn J. R. Davidsson, Samuel Birch, Geoffrey A. Blake, Dennis Bodewits, Jason P. Dworkin, Daniel P. Glavin, Yoshihiro Furukawa, Jonathan Lunine, Julie L. Mitchell, Ann N. Nguyen, Steve Squyres, Aki Takigawa, Jean-Baptiste Vincent, Kris Zacny
Summary: This study focuses on the transfer process of material on an active comet nucleus, specifically 67P/Churyumov-Gerasimenko. The research finds that the thickness of airfall material varies significantly with location, with water ice being able to be preserved for a longer period in relatively small dust aggregates.
Article
Astronomy & Astrophysics
M. Lippi, M. Vander Donckt, S. Faggi, Y. Moulane, M. J. Mumma, G. L. Villanueva, E. Jehin
Summary: This study investigates the composition of comet C/2021 A1 (Leonard) using CRIRES+ and TRAPPIST-South instruments. The results show that the abundance of CH3OH, C2H6, and CH4 in this comet, as measured in the infrared, is lower than average, suggesting a depletion in organics. However, measurements in the near UV-Visible spectral region show a C-2/CN ratio within the typical range. These different conclusions highlight the need for further investigations to comprehensively interpret the processes occurring in the comet's coma.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
M. R. Combi, T. Makinen, J. -l. Bertaux, E. Quemerais, S. Ferron
Summary: The hydrogen comae of three long period comets, C/2020 S3 (Erasmus), C/2021 A1 (Leonard), and C/2021 O3 (PanSTARRS), were observed using the Solar Wind ANisotropies (SWAN) all-sky hydrogen Lyman-alpha camera on the SOlar and Heliosphere Observer (SOHO) satellite in 2021 and 2022. SWAN captures daily full-sky images of the interstellar hydrogen's Lyman-alpha distribution as it passes through the solar system, providing information about the solar wind and solar ultraviolet fluxes. Water production rates were calculated for each comet over time. The behavior of comet C/2020 S3 (Erasmus) was typical, while comet C/2021 O3 (PanSTARRS) appeared to disintegrate before perihelion and comet C/2021 A1 (Leonard) disintegrated after its perihelion peak.
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.