Charged particles constitute one of the essential physical elements within the lunar space environment. Their origins, compositions and energy spectra are remarkably complex, and their spatial distribution and temporal dynamics are intricately coupled with localized electromagnetic field structures, rendering the lunar space environment fundamentally distinct from that of Earth or other magnetized planetary bodies. Compared to Earth, our methods for probing the lunar space environment remain relatively limited, both in terms of observational techniques and detection frequency. Notably, in situ measurements within the critical region encompassing the lunar surface and the low-altitude zone below 20 kilometers are exceptionally sparse. These observational gaps have collectively led to a fragmented and incomplete understanding of the fundamental characteristics of lunar charged particles, including their genesis, density fluctuations, dynamic behavior, as well as their potential spatial effects and associated hazards for exploration infrastructure and human activity. This review aims to synthesize and systematically organize the research findings from observations of lunar charged particles dating back to the Apollo era, endeavoring to present a coherent picture of the current state of knowledge and the trajectory of exploration. Recognizing that our comprehension of extraterrestrial space is profoundly shaped by the execution of national and international deep-space exploration programs, Section 1 begins by cataloging the key lunar missions undertaken by various nations, along with their primary scientific payloads and objectives. This historical overview is intended to illustrate the shifting priorities and evolving interests in lunar exploration over the decades. Given the inextricable coupling between charged particles and ambient electromagnetic fields, Section 2 provides a concise summary of the current understanding of lunar electromagnetic fields, encompassing both crustal magnetic anomalies and global fields, either transiently induced or permenantly intrinsic. The core of this review is structured along two parallel analytical threads. The first, covered in Sections 3 through 5, focuses on the "Background space environment along lunar orbit and its interactions with the Moon". This part examines the solar wind and geomagnetospheric plasma populations as they encounter and interact with the Moon, leading to phenomena such as absorption, reflection, and the formation of wake structures. The second thread, spanning Sections 6 to 11, is organized by "Types of charged particles in lunar space". Here, we systematically review observational results and theoretical models pertaining to specific particle populations, including photoelectrons, secondary electrons, exospheric neutrals, lunar dust, high-energy rays, and particles generated by human activities. Throughout this synthesis, it becomes evident that significant discrepancies and even outright contradictions exist, not only between theoretical predictions and observational data but also among different observational datasets themselves. These inconsistencies highlight the challenges inherent in remote and in situ space physics measurements and point to critical gaps in our current knowledge. Such uncertainties and unresolved questions likely define the most promising and necessary directions for future targeted investigations, requiring more advanced instrumentation, coordinated multi-point measurements, and sustained observation campaigns to unravel the complex electrodynamic environment of our closest celestial neighbor.

Venus, the planet closest to Earth, has a slowly retrograde rotation in the opposite direction to Earth's, and it has a dense atmosphere that exhibits rapid westward motion. At the cloud top, around 65–70 km in altitude, zonal wind speeds reach up to 100 m/s—about 50–60 times faster than the surface rotation. This striking and enigmatic phenomenon is known as atmospheric superrotation. Since the 1960s, the spatiotemporal characteristics and angular momentum balance mechanisms of superrotation have remained one of the central challenges in planetary atmospheric dynamics, with sustained investigation for over six decades. This review summarizes the historical development of superrotation studies and highlights recent advances. In terms of the vertical structure, superrotation intensifies from the surface upward, peaking near the cloud top, then gradually weakens toward the mesopause at around 110 km, where the circulation is dominated by the diurnal cycle. In the latitudinal distribution, the cloud-top winds maintain nearly constant at its maximum values between 50°N and 50°S before decreasing toward the poles. Superrotation is generally understood to be maintained by angular momentum transport through the combined effects of atmospheric circulation and large-scale eddies (such as tides and planetary waves). Recent observations and modeling results indicate that thermal tides primarily drive eddy contributions at the cloud top. In contrast, those in the middle and lower cloud layers (50–60 km) are mainly controlled by planetary waves. Furthermore, long-term observations have revealed multiple timescales of variability in superrotation, ranging from a few days to several hundred days, and possibly up to ~12 years linked to the solar cycle. State-of-the-art modeling studies suggest that the dynamic balance of angular momentum transport between planetary waves and the general circulation largely regulates the quasi-200-day variability in the cloud region. Overall, research on superrotation has been shifting from a focus on its basic maintenance mechanisms to its spatiotemporal variability, and from large-scale processes to smaller-scale phenomena such as gravity waves. With advances in numerical models and future observational missions, a more comprehensive understanding of the origin and evolution of Venusian atmospheric superrotation within a climatic framework is anticipated.

The atmospheres of gas giant planets contain multi-scale vortex structures, which are not only key components of planetary weather systems but also important windows for understanding their internal dynamics and thermodynamic processes. This paper reviews recent advances in the study of atmospheric vortices on gas giants, covering their formation mechanisms, evolution, spatial distribution, lifetime characteristics, and interactions with background wind fields. It focuses on typical phenomena such as Jupiter's Great Red Spot and polar vortices, Saturn's hexagonal storm, and discusses the roles of theoretical analysis, numerical simulations, and remote sensing observations in revealing vortex dynamics. From a theoretical perspective, this paper emphasizes the convective formation mechanisms of gas giant vortices, including two scenarios: moist convection in the weather layer and deep thermal convection. Moist convection in the weather layer is primarily driven by latent heat release associated with solar heating, where disturbed airflows rotate and merge under the influence of the Coriolis force to form large-scale vortices. Deep thermal convection, on the other hand, is driven by internal heat at the base of the convective layer, forming vortex tubes that subsequently merge into large-scale vortices. Both mechanisms involve vortex formation through convection, but differ in heat source depth, resulting in variations in the vertical extent of vortices. Considering the complexity of Jupiter's atmosphere, these two mechanisms may act together in vortex formation. In terms of numerical simulations, this paper explores possible causes of vortex formation based on rotating convection simulations in fluid dynamics, including shallow-water wave models, incompressible fluid models, and compressible fluid models. The shallow-water wave model primarily investigates the evolution of random disturbances in the stratosphere under rotational effects, while incompressible and compressible fluid models simulate the evolution of vortical elements in thin-layer and thick-layer convection, respectively. Simulation results show that all these models can generate large-scale vortices, suggesting they may represent important mechanisms for vortex formation in gas giant atmospheres. The specific formation mechanisms of atmospheric vortices on gas giants still require further integrated research combining theory, simulation, and observation. This paper aims to provide insights and references for a deeper understanding of the complex weather systems of gas giant planets.

Jupiter and Saturn, as the gas giants of our solar system, account for over 90% of the total mass beyond the Sun and hold most of the system's angular momentum, playing a crucial role in the early history of the solar sys- tem. During their formation, these planets captured vast amounts of material from the protoplanetary disk. Their in- ternal structure and interior composition are fundamentally affected by material interaction, gravitational collapse, and subsequent long-term thermal evolution. Exploring the interior structure of the gas giants provides critical in- sights into several core questions in planetary sciences, including the conditions and evolutionary history of the pro- tosolar nebula, the formation and evolution mechanisms of solar system planets, and the interior structure and evolu- tion history of giant exoplanets. Furthermore, comparative studies between Jupiter and Saturn reveal important dif- ferences in their internal dynamics and evolutionary pathways, offering valuable benchmarks for understanding gi- ant planets both within and beyond our solar system. Current research on the interior structure of the gas giants primarily relies on external observational constraints such as gravity fields, magnetic fields, and atmospheric properties. However, inferring the interior structure from these constraints is inherently a highly degenerate inver- sion problem, depending on interior structural models, internal material properties, and calculations of planetary shape and gravity fields. Modern approaches increasingly integrate multiple physical constraints by combining gravity harmonics with magnetic field measurements and zonal wind profiles to reduce degeneracies in interior models. In recent years, the Juno and Cassini spacecraft have conducted close orbital explorations of Jupiter and Saturn, respectively, acquiring unprecedented high-precision gravity field data. Simultaneously, experimental and theoretical research on the physical properties of hydrogen and helium under extreme temperature and pressure conditions has achieved critical breakthroughs. With these in mind, this paper reviews the major exploration mis- sions for Jupiter and Saturn and elaborates on the core aspects of interior modelling, such as theoretical calcula- tions of planetary shapes and gravity fields, current knowledge of hydrogen/helium microphysical properties. The research progress on the internal structures of Jupiter and Saturn is also summarized, showing some representative frontier achievements.

Abstract: The auroral arc is a common form of aurora. Its formation involves three processes: the transfer of disturbed energy from the source region to the acceleration region via Alfvén waves, the generation of acceleration structures within the acceleration region, and the acceleration of electrons to produce aurora. Observations indicate that the auroral arc corresponds to a quasi-static parallel electric field with a U-shaped structure, with a clear concentration of the electric field at the bottom of the U-shaped structure. Regarding how the initial energy input evolves into a quasi-static electric field with a U-shaped structure, simulation studies based on existing auroral particle acceleration theories have not yet fully reproduced results that are fully consistent with the observed characteristics. This suggests that the existing theory may still lack a description of a key energy conversion process. Our research indicates that the core of this process lies precisely in the modified electron acoustic wave unique to the transition region. Based on this, we have constructed a dynamic theoretical model that incorporates, for the first time, the coupling of modified electron acoustic waves and kinetic Alfvén waves. The model's output is in good agreement with the observed characteristics of the U-shaped structure, directly revealing the decisive role of modified electron acoustic waves in the formation and evolution of the quasi-static electric field. This achievement provides a new physical foundation for improving the theory of auroral particle acceleration.

Intense solar activity is a major driver of hazardous space weather. The associated processes, including strong electromagnetic radiation, plasma ejections, and high-energy particle acceleration, can significantly disturb the Sun-Earth environment within a short time and further trigger a series of chain effects such as ionospheric disturbances and high-frequency communication interruptions, thereby posing serious threats to critical sectors including aviation, aerospace, and telecommunications. With the continuous advancement of space technology, society has placed increasingly higher demands on space-weather monitoring with high accuracy and reliability. Consequently, the development of high-performance solar radio observing systems has become an important approach to improving space-weather forecasting and mitigation capabilities. In solar physics, radio emissions at different frequencies correspond to radiation mechanisms occurring at different heights and under different plasma-density conditions in the solar atmosphere. Therefore, obtaining observational data with the broadest possible frequency coverage is not only crucial for revealing the acceleration mechanisms of high-energy electrons in solar flares, but also provides important support for understanding the spatiotemporal evolution of solar eruptions. From the perspective of instrumentation development, it is thus of great significance to establish solar radio observing systems with broader frequency coverage and higher temporal and spectral resolutions. This paper systematically reviews the development of solar radio observing instruments worldwide, summarizes the structural characteristics of representative radio telescopes and spectrometers from the decimeter, centimeter, to millimeter wavelength bands, and compares their system designs, signal-processing chains, and frequency coverage. On this basis, the current status of solar radio observing facilities is analyzed, and the key technical bottlenecks and future development trends are discussed. It is hoped that this review will provide useful references for the planning, design, and key-technology development of future solar radio observing systems.

The all-sky imager is an important ground-based auroral observation equipment. Accurate optical geometric correspondence between "object-image" is the foundation for obtaining the structural scale of auroras and achieving joint observations between the all-sky imager and satellites. This paper proposes a geometric calibration method for all-sky imagers based on gradient descent and star maps. This method determines the coordinates of each star point in the star map within the all-sky image, and uses gradient descent to determine the pixel position of the zenith in the all-sky image, as well as the relationship between the imaging radius and zenith angle within the field of view. 26 and 22 star points were marked in all-sky images taken at two different times, respectively, and the calibration results were verified by comparing them with the corresponding star maps. The verification results showed that the absolute values of the stellar azimuth angle errors were 0.154 7° and 0.206 2° on average, and the absolute values of the zenith angle errors were 0.107 6° and 0.113 3° on average, respectively. This indicates that the calibration method proposed in this paper is accurate and effective.