Article
Astronomy & Astrophysics
O. Kawashima, T. Morota, M. Ohtake, S. Kasahara
Summary: The concentrations of volatiles, particularly hydrogen or water, at the lunar poles have been studied through remote sensing data. This research focuses on the geomorphological analysis of Shackleton Crater at the South Pole and Whipple Crater at the North Pole. The results suggest a low production rate of boulders in these regions and the possibility of small craters being covered and preserving subsurface water molecules. Feasible landing sites and scenarios for exploring local subsurface water using excavators are proposed based on the findings.
Article
Astronomy & Astrophysics
A. Kereszturi, R. Tomka, V Steinmann
Summary: This work presents and tests a method for age estimation of lunar terrains based on classical crater size frequency distribution statistical analysis, comparing optical and topographic data to identify craters with consistent results. Using this method, the age values of different areas in DeGerlache crater were determined, showing agreement with previous research.
Article
Geosciences, Multidisciplinary
Lon L. L. Hood, Isabella Bryant, Jacob van der Leeuw
Summary: This study reveals the presence of anomalies in the crustal magnetic fields near the lunar south pole, which are correlated with the distribution of exposed water ice. These anomalies effectively reduce the ion flux of the solar wind, resulting in a lower rate of water ice loss.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geochemistry & Geophysics
Niutao Liu, Ya-Qiu Jin
Summary: This letter discusses the plan for direct sampling in the permanently shadowed regions (PSRs) of lunar poles using a mini-flyer in the Chinese Chang'e-7 (CE-7) mission. The potential craters of Shackleton, Shoemaker, de Gerlache, and Slater are considered, and the design principles of the landing site, sampling site, and flight route are presented. Surface slopes are calculated using a digital elevation model (DEM) and Mini-RF data is used for validation.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Chemistry, Physical
Tianxi Sun
Summary: This article points out the presence of methanol and hydrogen ice on the Moon, and emphasizes the need to re-investigate water ice within lunar polar craters. It also explains the chemical reactions between interstellar methanol ice and lunar carbon-rich regolith that produce molecular hydrogen, and elucidates the mechanism of hydrogen ice formation. The author suggests that hydrogen ice within lunar polar craters can serve as a fuel base for interplanetary flight.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Review
Environmental Sciences
Alistair Duffey, Peter Irvine, Michel Tsamados, Julienne Stroeve
Summary: Solar geoengineering, such as stratospheric aerosol injection (SAI), aims to mitigate climate change by reflecting sunlight away. This review examines the impacts of SAI on polar climate and cryosphere, emphasizing the need for future research in these areas. Utilizing SAI could cool and stabilize the polar regions under future warming scenarios, but there may be limitations in preventing winter-time polar climate changes and sea-level rise from the Antarctic ice sheet. Other solar geoengineering proposals targeting the poles, such as marine cloud brightening and cirrus cloud thinning, require further investigation to determine their effectiveness. A robust understanding of solar geoengineering's consequences in the polar regions is crucial for informing climate policy.
Article
Environmental Sciences
Zhiyong Xie, Peng Zhang, Zilan Wu, Shuang Zhang, Lijia Wei, Lijie Mi, Anette Kuester, Juergen Gandrass, Ralf Ebinghaus, Ruiqiang Yang, Zhen Wang, Wenying Mi
Summary: This paper reviews the occurrence and transport processes of emerging organic contaminants (EOCs) and legacy persistent organic pollutants (POPs) in polar regions. It highlights the differences between the Arctic and Antarctica, and the potential effects of remobilization on pollutant concentrations.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Multidisciplinary Sciences
V. T. Bickel, B. Moseley, I Lopez-Francos, M. Shirley
Summary: A deep learning algorithm has been developed to enhance images of permanently shadowed regions on the Moon, revealing previously unseen geomorphological features and water-ice distribution within PSRs. This significantly aids in the exploration of PSRs by reducing uncertainty in target selection and mission planning.
NATURE COMMUNICATIONS
(2021)
Article
Environmental Sciences
Keshao Liu, Tandong Yao, David A. Pearce, Nianzhi Jiao, Yonghui Zeng, Bixi Guo, Yongqin Liu
Summary: The Tibetan Plateau, known as 'the Third Pole', has the highest number of high-altitude lakes in the world, sharing environmental features with polar regions. Despite similar environmental conditions, the spatial distribution of bacterial communities in the lakes showed distinct patterns, with evidence of dispersal limitation. Climatic variables and dispersal limitation were both important in controlling the spatial distribution of bacterial communities across regions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Engineering, Aerospace
Hong Gan, Chengxuan Zhao, Guangfei Wei, Xiongyao Li, Guojun Xia, Xiao Zhang, Jingjing Shi
Summary: The lunar polar regions have continuous illumination and shadowed regions that can trap water and volatiles, making them important areas for future exploration. However, investigating these areas poses challenges due to complex terrain, dynamic lighting, and electric-field environment. China's Chang'E-7 mission aims to explore the Moon's south polar region in 2026 and one of its goals is to drill samples for in situ analysis. This study analyzes the engineering constraints of polar conditions and creates a 3D model of CE-7's lunar rover to study the charging effects under different environmental conditions. The results provide important implications for minimizing charging effects during lunar polar region exploration.
Article
Engineering, Aerospace
Shashi Kumar, Awinash Singh, Aanchal Sharma, Vaishali Chaudhary, Ashish Joshi, Shefali Agrawal, Prakash Chauhan
Summary: In order to confirm the presence of water on the moon, many scientists are making continuous efforts through remote sensing data. This study utilizes the data collected by the Dual Frequency Synthetic Aperture Radar (DFSAR) sensor of the Chandrayaan-2 mission to analyze and detect ice in the permanently shadowed regions (PSRs) of lunar South Polar craters. The analysis of polarimetric parameters and indices, in conjunction with geomorphological parameters, provides a reference for the unambiguous identification of surface ice clusters in the PSRs.
ADVANCES IN SPACE RESEARCH
(2022)
Article
Astronomy & Astrophysics
H. M. Brown, A. K. Boyd, B. W. Denevi, M. R. Henriksen, M. R. Manheim, M. S. Robinson, E. J. Speyerer, R. Wagner
Summary: The lunar polar regions contain permanently shadowed regions that can cold-trap volatile materials in the form of ice, which are important resources for exploration. This study compiles observations to estimate the locations and mass of water ice deposits in PSRs.
Article
Biodiversity Conservation
Francesca Leasi, Joseph L. Sevigny, Brandon T. Hassett
Summary: Establishing robust estimates of polar marine biodiversity is important for interpreting future changes in the Arctic. Despite the recent increase in scientific expeditions, the region remains relatively underexplored, particularly in terms of small species like protists, fungi, and many small invertebrates known as meiofauna. The study used a metabarcoding approach to assess metazoan biodiversity in sea ice and sediment samples from Utqiagvik, Alaska, and found that season and habitat are significant predictors of meiofaunal biodiversity, supporting the use of meiofauna as indicators of climate change.
ECOLOGICAL INDICATORS
(2021)
Article
Physics, Multidisciplinary
Qing Xia, Ming-Hui Cai, Liang-Liang Xu, Rui-Long Han, Tao Yang, Jian-Wei Han
Summary: This study investigates the spatial distribution of charged lunar dust in the south polar region of the moon and the effects of a mini-crater. The density of lunar dust varies with different solar altitude angles, and a mini-crater creates a quasi-neutral electric environment with lower dust density. There is significant transport of charged lunar dust in the region between light and shade.
Article
Geosciences, Multidisciplinary
Ziyu Huang, Ken-ichi Nomura, Liam S. Morrissey, Joseph Wang
Summary: Reactive molecular dynamics simulations were used to study solar wind implantation on the lunar surface and its contribution to lunar water formation. The study found that while solar wind implantation can lead to the formation of hydroxyl groups and water molecules, its contribution to the observed lunar water content is not significant.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
Z. Girazian, J. Halekas, R. J. Lillis
Summary: Using MAVEN observations, we studied the variations in the structure and composition of the nightside ionosphere on Mars on solar cycle and seasonal timescales. Plasma densities vary significantly at fixed altitudes due to variations in thermospheric pressure levels. The electron impact ionization (EII) rate, influenced by solar cycle and seasonal trends, also affects the nightside densities. High-altitude nightside ionosphere densities vary significantly over the solar cycle, with topside O+ and O+2 densities changing by factors of -50 and -40, respectively. Topside ion densities remained relatively stable during the solar minimum of 2018-2019.
Article
Astronomy & Astrophysics
R. D. Jolitz, A. Rahmati, D. A. Brain, C. O. Lee, R. J. Lillis, E. Thiemann, F. Eparvier, D. Mitchell, J. Halekas, D. Larson, S. M. Curry, B. M. Jakosky
Summary: Solar extreme ultraviolet (EUV) radiation, solar wind, and solar energetic particles (SEPs) are sources of ionization and heating to the Martian atmosphere. MAVEN's orbit allows it to measure these solar drivers upstream of Mars. By averaging observations over several months, the study found that EUV and solar wind ions are the dominant contributors to energy fluxes, while SEPs play a smaller role. The study also identified the presence of strong and weak coronal mass ejections, which can impact the energy fluxes on the nightside.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Editorial Material
Geochemistry & Geophysics
Fabio Florindo, Valerio Acocella, Ann Marie Carlton, Paolo D'Odorico, Qingyun Duan, Andrew Gettelman, Jasper Halekas, Ruth Harris, Gesine Mollenhauer, Alan Robock, Claudine Stirling, Yusuke Yokoyama
Summary: Reviews of Geophysics is an AGU journal that publishes comprehensive review articles across various disciplines within the Earth and Space Sciences. It is a highly ranked journal in the fields of Geochemistry and Geophysics, with a high Journal Impact Factor (JIF). The journal's review papers provide crucial context for current work, establishing a framework for comprehensive understanding of research progress and interconnections between different communities.
REVIEWS OF GEOPHYSICS
(2023)
Article
Geochemistry & Geophysics
L. Ram, D. Rout, R. Rathi, S. Mondal, S. Sarkhel, J. Halekas
Summary: Measurements from MAVEN spacecraft are used to investigate the impact of CMEs and CIRs on Martian ionospheric species. 15 CMEs and 15 CIRs events from 2015 to 2020 are analyzed, and significant differences in ionospheric species profiles are observed during these events. The study suggests that CIRs have a more prominent impact on the Martian ionospheric species than CMEs during the declining phase of solar cycle 24.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Astronomy & Astrophysics
Daniele Telloni, Marco Romoli, Marco Velli, Gary P. Zank, Laxman Adhikari, Lingling Zhao, Cooper Downs, Jasper S. Halekas, Jaye L. Verniero, Michael D. Mcmanus, Chen Shi, Aleksandr Burtovoi, Roberto Susino, Daniele Spadaro, Alessandro Liberatore, Ester Antonucci, Yara De Leo, Lucia Abbo, Federica Frassati, Giovanna Jerse, Federico Landini, Gianalfredo Nicolini, Maurizio Pancrazzi, Giuliana Russano, Clementina Sasso, Vincenzo Andretta, Vania Da Deppo, Silvano Fineschi, Catia Grimani, Petr Heinzel, John D. Moses, Giampiero Naletto, Marco Stangalini, Luca Teriaca, Michela Uslenghi, Stuart D. Bale, Justin C. Kasper
Summary: This paper presents the first direct investigation of the energy budget in the solar corona. Using joint observations from Parker Solar Probe and Solar Orbiter's Metis coronagraph, the authors estimate the values of different factors contributing to the energy flux of the proton component of the slow solar wind. The results reveal that magnetic fluctuations, including Alfven waves, are the primary source of solar wind energy near the Sun, while kinetic energy dominates at higher altitudes.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
R. Bandyopadhyay, C. M. Meyer, W. H. Matthaeus, D. J. McComas, S. R. Cranmer, J. S. Halekas, J. Huang, D. E. Larson, R. Livi, A. Rahmati, P. L. Whittlesey, M. L. Stevens, J. C. Kasper, S. D. Bale
Summary: This study focuses on the heating mechanism of protons and electrons in space plasma physics, with differential heating playing a key role in solar wind evolution. Using data from Parker Solar Probe, the researchers found significant differences in heating behavior between protons and electrons compared to previous reports, with proton heating becoming more dominant at decreasing distances from the Sun.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Geochemistry & Geophysics
Shaosui Xu, Andrew R. Poppe, Paul S. Szabo, Yuki Harada, Jasper S. Halekas, Phillip C. Chamberlin
Summary: Lunar surface charging is a significant research topic, and the observation of oxygen Auger electrons provides insights into the backscattering coefficient and its dependence on the magnetic dip angle.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Geochemistry & Geophysics
D. Bhattacharyya, J. T. Clarke, M. Mayyasi, V. Shematovich, D. Bisikalo, J. Y. Chaufray, E. Thiemann, J. Halekas, C. Schmidt, J. L. Bertaux, M. S. Chaffin, N. M. Schneider
Summary: The recent discovery of higher escape rates of hydrogen atoms near Mars' perihelion suggests substantial water loss from Mars, surpassing previous theories. This study provides the first confirmed observation of energetic hydrogen atoms in Mars' atmosphere, which are believed to be produced by interaction with solar wind through charge exchange.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Astronomy & Astrophysics
Xiaohua Fang, Yingjuan Ma, Janet Luhmann, Yaxue Dong, Jasper Halekas, Shannon Curry
Summary: This study investigates the global distribution and variability of the external magnetic field at Mars, examining its relationship with the solar wind dynamic pressure, interplanetary magnetic field, and ambient crustal magnetic field strength. Using measurements from the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission and magnetohydrodynamic simulations, the researchers find that the external magnetic field is significantly enhanced from the upstream across the bow shock and intensifies closer to the planet in the topside ionosphere. The external field exhibits a strong day-night asymmetry and may be enhanced under high solar wind dynamic pressures and interplanetary magnetic fields.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Jacob Fruchtman, Jasper Halekas, Jacob Gruesbeck, David Mitchell, Christian Mazelle
Summary: The Martian bow shock exhibits foot, ramp, and overshoot substructures, which are not affected by the seasonal variability of the Sun-Mars system. The properties of the solar wind, rather than Mars' location in its orbit, primarily control the structure of the bow shock.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Andrea C. G. Hughes, Michael Chaffin, Edwin Mierkiewicz, Justin Deighan, Rebecca D. Jolitz, Esa Kallio, Guillaume Gronoff, Valery Shematovich, Dmitry Bisikalo, Jasper Halekas, Cyril Simon Wedlund, Nicholas Schneider, Birgit Ritter, Zachary Girazian, Sonal Jain, Jean-Claude Gerard, Bradley Hegyi
Summary: Proton aurora at Mars, which are commonly observed but least studied, are investigated through a multi-model comparison campaign in this study. Four different proton/hydrogen precipitation models are compared, and their capabilities and limitations are assessed by modeling representative cases. The study finds that the incident solar wind particle flux and velocity are the primary variables affecting proton aurora. The robustness and effectiveness of each model in reproducing proton aurora observations are evaluated, and it is concluded that the appropriate physical processes and parameters have been identified.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Masahisa Kato, Yuki Harada, Shaosui Xu, Andrew R. Poppe, Jasper S. Halekas, Yohei Miyake, Hideyuki Usui, Masaki N. Nishino, Toru Matsumoto
Summary: Due to the lack of a dense atmosphere, the Moon interacts directly with ambient plasmas and solar radiation, causing surface charging. This study developed a numerical model to analyze the energy spectrum of lunar photoelectrons and Auger electrons. The comparison between the model and observations suggests that the emitted electrons can be used to remotely infer the lunar surface potential.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Han-Wen Shen, Jasper S. Halekas, Andrew R. Poppe
Summary: Using measurements from the ARTEMIS mission, this study investigates the plasma density near the lunar surface. The results show that there is no evidence of a steady-state or global lunar ionosphere, as the plasma densities do not exceed 35 cm-3 at altitudes between 10 and 50 km. The density profiles also vary with local time and altitude, with higher density observed in the sunlit sector compared to the shadowed sector.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Shaosui Xu, Janet G. Luhmann, David L. Mitchell, Tristan Weber, David A. Brain, Yingjuan Ma, Shannon M. Curry, Gina A. Dibraccio, Jasper Halekas, Suranga Ruhunusiri, Christian Mazelle, Robert J. Lillis, Benoit Langlais
Summary: In this study, the authors investigate the role of large-scale planetary fields in Mars's magnetospheric responses to the interplanetary magnetic field. They find that the dipole-like planetary field has a similar influence on Mars's magnetosphere as it does on Earth, resulting in a more open magnetosphere during certain conditions.
ASTROPHYSICAL JOURNAL LETTERS
(2023)
Article
Astronomy & Astrophysics
Jacob Fruchtman, Jasper Halekas, Jacob Gruesbeck, David Mitchell, Christian Mazelle
Summary: The structure of the Martian bow shock is mainly controlled by the properties of the solar wind, rather than by the seasonal variability of the Sun-Mars system.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
