Heliophysics, a highly active and foundational frontier of contemporary natural science, stands as a critical interdisciplinary field encompassing solar physics, space physics, space weather and plasma physics. It is of paramount importance for understanding the physical processes of the Sun-Earth system and the solar system as a whole, as well as for ensuring the security of human high-technology activities in space. Since the successful launch of the first artificial satellite in 1957 ushered in a new era of space exploration, humanity has deployed hundreds of specialized spacecraft to investigate the myriad phenomena within our heliosphere. The synergistic use of remote sensing and in-situ measurements, integrated with extensive ground-based observations and sophisticated numerical models, has yielded numerous breakthrough discoveries. These advancements have profoundly enhanced our understanding of the Sun's influence on the solar system and the complex space environment surrounding Earth. This paper presents a comprehensive review of the current research status and future development trends in heliophysics, both domestically and within China. It synthesizes significant scientific achievements and cutting-edge advancements in recent years across four key domains: (1) the Sun and the heliosphere; (2) Earth's magnetosphere; (3) the ionosphere and the middle-upper atmosphere; and (4) the space environments of the Moon and other planets. Our analysis indicates that the international research paradigm is progressively expanding from a focused study of the "Sun-Earth system connection" to a holistic exploration of the "Sun-Solar System connection". Concurrently, technological advancements in wide-field imaging and constellation-based missions are significantly enhancing our observational capabilities for both macroscopic and meso-to micro-scale three-dimensional structures. Furthermore, comparative planetology and the study of planetary habitability are gaining increasing prominence. Domestically, China's heliophysics research has established a considerable ground-based monitoring network, is accelerating the construction of its space-based detection systems, and is continuously strengthening its academic foundations, leading to a steady emergence of original scientific outcomes. Looking toward the future, and aligned with the strategic deployment outlined in the recently released "National Space Science Mid-and Long-Term Development Plan (2024-2050)", this paper provides an in-depth discussion of ten critical scientific questions that China aims to address. These questions include: (1) the characteristics of magnetic activity in the solar polar regions and the formation mechanism of the solar magnetic cycle; (2) the cross-scale processes and mechanisms governing solar wind-magnetosphere interactions; (3) the processes and mechanisms of the solar wind's interaction with the interstellar medium; (4) the three-dimensional propagation characteristics of solar wind disturbances and the prediction of the southward magnetic field; (5) the influence of inner magnetospheric wave-particle interactions on the three-dimensional structure and evolution of radiation belts; (6) the coupling processes between the magnetosphere, ionosphere, and thermosphere, and the dynamics of polar particles; (7) the causes and variability of multi-scale disturbance structures in the ionosphere/thermosphere; (8) the coupling processes and mechanisms between Earth's geodynamic activity, atmosphere, and ionosphere; (9) the space weather environment and the mechanisms of matter and energy circulation in giant planet systems; and (10) the influence and mechanisms of space weather on planetary habitability. This paper aims to provide a comprehensive scientific reference for China's future deployment of research initiatives and strategic planning in heliophysics.

The Global Atmospheric Circuit is a key link connecting the Earth's surface, atmosphere, and ionosphere, regulating global charge transport and exhibiting high sensitivity to perturbations from solar activity. On 10 May 2024, a super geospace storm struck Earth, representing the strongest Sun-Earth interaction event since the 2003 Halloween storms. This event drove an extreme magnetospheric storm with a 15.4% Forbush decrease event and the compression of the magnetosphere to approximately 5 Earth radii. To explore the response patterns and mechanisms of the Global Atmospheric Circuit, we analyzed 3 months of continuous observational data (including the vertical atmospheric electric field, atmospheric electrical conductivity, and conduction current density) from the Paratunka Observatory, a coastal site with minimal local anthropogenic and topographic interference. We first established the fair-weather baseline curves of these atmospheric electrical parameters, then calculated their deviations, and correlated these deviations with neutron monitor data that reflect the variations of Galactic Cosmic Rays. Results show that the May 2024 geospace storm drove an intense Forbush decrease, which further triggered significant perturbations in the Global Atmospheric Circuit. Specifically, the perturbations of conduction current density and atmospheric electric field exceeded five times the levels of a quiet period, while the near-surface atmospheric electrical conductivity remained almost unchanged. A possible sphere coupling process was discussed in this study. In conclusion, this study provides direct observational evidence of the response of the Global Atmospheric Circuit to extreme solar activity, which advances our understanding of the coupling between solar activity, the magnetosphere, and the lower atmosphere.

Following a southward turning of the interplanetary magnetic field (IMF), dayside magnetic reconnection rapidly re-establishes sunward convection on closed field lines, modifying plasma flow near the magnetopause. How magnetopause Kelvin–Helmholtz (KH) vortices develop and inflxuence magnetospheric convection under southward IMF conditions remains unclear. Here, we use global magnetohydrodynamic (MHD) simulations to investigate the formation, evolution, and convection impact of KH vortices under fast (800 km/s) and slow (400 km/s) solar-wind conditions.After the IMF turns southward, KH vortices form along the magnetopause and extend across the low-latitude boundary layer (LLBL) into the closed-field-line convection region, locally distorting the global convection pattern. Regardless of solar-wind speed, the azimuthal region of distorted convection near magnetic local time 06 exhibits a characteristic thickness of approximately 3–4 RE (~3° in magnetic latitude). These vortices and associated convection perturbations propagate antisunward. Compared with slow solar-wind cases, fast solar-wind conditions lead to more rapid earthward propagation and deeper penetration of the distorted convection into the inner magnetosphere. These results demonstrate that inner magnetospheric convection can be shaped by LLBL instabilities in the southward IMF.

Context. Airless planetary bodies are directly exposed to solar wind ions, which can scatter or become implanted upon impact with the regolith-covered surface, while also sputtering surface atoms. Aims. We constructed a semi-analytical model for the scattering of ions of hundreds of electron volts (eV) and the sputtering of surface atoms, both resulting in the emission of negative ions from the lunar surface. Our model contains a novel description of the scattering process that is physics-based and constrained by observations. Methods. We used data from the Negative Ions at the Lunar Surface (NILS) instrument on the Chang'e-6 lander to update prior knowledge of ion scattering and sputtering from lunar regolith through Bayesian inference. Results. Our model shows a good agreement with the NILS data. We find that a precipitating solar wind proton has a roughly 22(-6.1)(+4.9) % chance of scattering from the lunar surface in any charge state and 8.1(-3.9)(+7.9) % chance of sputtering a surface hydrogen atom. The resulting ratio of scattered to sputtered hydrogen flux is eta(sc)/eta(sp) = 1.5(-1.1)(+1.5) for a proton speed of 300 km/s. We found a high probability (7-20%) that a hydrogen atom leaves the surface negatively charged. The angular emission distributions at near-grazing angles for both scattered and sputtered fluxes are controlled by surface roughness. Our model also indicates significant inelastic energy losses for hydrogen interacting with the regolith, suggesting a longer effective path length than previously assumed. Finally, we estimated a surface binding energy of 5.5 eV, consistent with the observations. Conclusions. Our model describes the scattering and sputtering of particles of any charge state from any homogeneous, multi-species surface. Using NILS data, we successfully applied the model to update our understanding of solar wind interacting with lunar regolith and the emission of negative hydrogen ions.

The cusp region plays a crucial role in the interaction between the solar wind and the Earth's magnetosphere, where solar wind particles can enter the magnetosphere directly. This study reports that the cusp boundary exhibits a twisting structure, which intensifies with increasing altitude, as demonstrated by global magnetohydrodynamic (MHD) simulations. It is further revealed that the dawn-dusk component of the interplanetary magnetic field (IMF) significantly influences the degree of cusp twisting. This effect can be attributed to the tilt of the magnetic reconnection X-line and the subsequent tilt of the plasma flow directions, modulated by the IMF . Moreover, the relationship between the cusp twisting deformations at different altitudes and the magnitude of the IMF is quantitatively analyzed across the entire cusp region based on systematic MHD simulation runs. A remarkable enhancement in the twisting angle is indicated with increasing IMF and altitude, varying from 0 to 7.6. The orientation of the cusp twisting follows that of the magnetotail and current sheet dynamics reported in previous studies, implying that the cusp twisting reported here is an essential part of the global effect of non-zero IMF on the dayside magnetopause.

Abstract The Brewer‐Dobson circulation (BDC) is a fundamental driver of trace gas transport in the middle atmosphere. Direct quantification of its descent rate remains observationally challenging. Here, we leverage wintertime solar proton events (SPEs) as natural experiments and use ozone‐depletion trajectories as dynamical tracers to quantify polar stratospheric descent. Derived velocities range from 150 to 570 m/day, consistent with CO/NO tracer studies and WACCM simulations. We find a strong relationship between descent velocity and integrated proton flux (CC = 0.54, p = 0.01), indicating that stronger particle precipitation is associated with enhanced polar descent of ozone‐depletion tracers. This relationship is accompanied by coherent changes in ozone, temperature, zonal wind, and planetary‐wave forcing. We further show that the SPE‐related dynamical responses differ between quasi‐biennial oscillation (QBO) phases, with stronger planetary‐wave forcing during the QBO westerly phase. These results provide observational constraints on the linkage between energetic particle precipitation and stratospheric dynamical variability.

Injections of energetic ions into the inner magnetosphere constitute one of the main sources of ring current enhancements during geomagnetic storm main phases, especially for energies in the range of 10 similar to 200 keV. So far, the majority of investigations of energetic ion injections were performed at L > 4.0 in the inner magnetosphere, while the study of ion injections in L < 4.0 regions is scarcer. In this paper, we have developed a method to identify ion injections for L < 4.0 based on energetic ion fluxes versus L profiles during geomagnetic quiet times. We have selected 120 ion injections with 15 isolated injections and 105 storm-time injections based on the flux ratios between active and quiet periods. Energetic ions can be seldom injected into L < 3.0 during isolated substorms, while they can reach much deeper orbits during storm time. Additionally, we have calculated the correlation coefficients between the adjacent orbits during the geomagnetic active and quiet times in the same orbit categories. The results show that energetic ions with 150 similar to 750 keV are hardly injected into L < 4.0 for both ascending (from low L to high L) and descending (from high L to low L) orbit phases. In contrast, lower energy ions with 50 keV < E < 150 keV are regularly injected into L < 4.0 during geomagnetic storm-times, with the deepest injection depth at L = 2.4.

The Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) mission, a collaboration between the Chinese Academy of Sciences (CAS) and the European Space Agency (ESA), is scheduled for launch on 19 May 2026.

Gamma-ray bursts (GRBs) have long been proposed to perturb Earth's ionosphere, with occasional reports of disruptions in ultra- and extremely-low-frequency radio signals. The exceptionally bright GRB 221009A was recently claimed to induce multi-altitude ionospheric responses, including perturbations in satellite electric fields, regional total electron content (TEC), and the equatorial electrojet (EEJ). These claims have renewed interest in the potential near-Earth impacts of astrophysical transients. Here we perform an independent reassessment using expanded datasets spanning multiple altitudes. We find no coherent, burst-like TEC enhancement, show that the reported electric-field anomalies recur under specific illumination conditions each orbit, and demonstrate that the EEJ fluctuations preceded the burst and coincide with solar-wind variability. Together, these results indicate that the reported GRB-induced ionospheric responses are fully attributable to other natural geophysical processes and instrumental artefacts, thereby resolving a high-profile controversy and clarifying the true limits of GRBs'ionospheric effects.

Magnetic reconnection is a universal process that converts magnetic energy into particle energy. Although lower-hybrid waves (LHWs) have been widely studied in and near reconnection diffusion regions, their evolution and role in structuring the broader reconnection exhaust remain largely unexplored. Here we report direct observations of electron vortex arrays associated with LHWs. The observed waves drive coherent electron vortical flows that organize into ordered arrays along the ion jet boundary. Electron vortical flows and LHWs are observed in a mixed-ion reconnection environment containing cold magnetospheric ions and warm magnetosheath ions. The electron vortical flows are spatially nonuniform along the background magnetic field, suggesting that the vortex radius may vary along the field. These results demonstrate that wave-driven electron vortices play an important role in the fine-scale structuring of reconnection exhausts.

Unmanned Aerial Vehicles (UAVs) are becoming integral to the emerging low-altitude economy, operating primarily below 3,000 m for applications such as logistics, inspection, precision agriculture, and urban air mobility. The safe and reliable operation of UAVs depends critically on communication, navigation, and surveillance (CNS) systems, which provide command and control, precise positioning, and situational awareness. Although UAV hardware is largely protected from direct radiation hazards by the Earth's atmosphere and magnetosphere, space weather can still indirectly disrupt operations by affecting CNS performance. Solar flares, geomagnetic storms, and ionospheric irregularities can degrade communication links, induce navigation errors, and compromise surveillance reliability, posing risks to flight safety and operational continuity. This commentary highlights these vulnerabilities, reviews mechanisms through which space weather impacts UAV systems, and emphasizes the importance of integrating space weather awareness into UAV traffic management and system design to support a resilient low-altitude economy.

We examine the detailed electron dynamics within an electron diffusion region (EDR) with a moderate guide field (normalized guide field ~0.5), as observed by the Magnetospheric Multiscale (MMS) spacecraft at the magnetopause. Due to the presence of a moderate guide field, high-energy electrons (>300 eV) can be scattered, while low-energy electrons (

Kinetic impact is regarded as the most technically feasible method for asteroid defense.Conducting an on-orbit demonstration and verification mission would not only enhance the technological maturity of kinetic-impact deflection,but also reveal the orbital deflection behavior of near-Earth asteroids,thereby providing decision-making support for future responses to real near-Earth asteroid impact threats.The orbital dynamical characteristics and structural,physical,and chemical properties of near-Earth asteroids are critical to the successful implementation of kinetic-impact missions.At the same time,such missions would provide an unprecedented opportunity to investigate the internal structure,composition,and mechanical properties of near-Earth asteroids.In addition,kinetic impact would serve as a unique"natural experiment,"offering a key case study for impact physics from the perspective of comparative planetology and thereby promoting the coordinated development of planetary science and planetary defense technologies.Focusing on China's first asteroid defense demonstration and verification mission planned before 2030,this paper systematically reviews the frontier scientific questions in kinetic-impact asteroid defense,with the aim of providing a reference for mission design,implementation,and preliminary scientific research.

Electron Bernstein waves (EBWs) are electrostatic modes that propagate perpendicular to the magnetic field in magnetized plasmas, serving as a diagnostic tool for understanding plasma properties and the energetic particles that drive energy transport. However, their naturally occurring harmonic structures have long eluded ground-based radar detection due to their faint signals and the requirement for an observational geometry nearly perpendicular to the geomagnetic field. Here, we report high-resolution broadband spectral observations of naturally excited EBWs in Earth's ionosphere using the Sanya Incoherent Scatter Radar. Our measurements reveal a series of discrete, well-defined spectral lines corresponding to the first seven electron gyroharmonics, a result consistent with theoretical predictions. Our analysis suggests that these EBW modes, enhanced by suprathermal photoelectrons, become observable under near-perpendicular geometry, where Landau damping is reduced. The frequency structure of these harmonics acts as a precise diagnostic ruler that enables the retrieval of electron density and perpendicular electron temperature, parameters that are difficult to retrieve with ion line techniques under such geometric constraints. This work provides ground-based radar observations of naturally excited EBWs and shows their use for diagnosing plasma parameters in magnetized plasmas.

Context. Switchbacks–transient, large-angle deflections of the interplanetary magnetic field–pervade the solar wind, yet their origin remains disputed. Current ex situ theories, notably coronal jets and interchange reconnection, are typically tested on day-scale intervals. Aims. We aim to establish a connection between switchbacks and ex situ theories on solar-cycle timescales. Methods. We exploited 27 years of continuous in situ measurements from ACE, Wind, and STEREO-A/B at 1 au, complemented by synoptic remote-sensing data from SDO, to examine the solar-cycle modulation of switchback occurrence and to test whether ex situ scenarios (coronal jets and interchange reconnection) play a dominant role in such long-term modulation. Results. The switchback occurrence rate correlates strongly with Alfvénicity (cc = 0.70 ± 0.04) and shows no solar-maximum preference (independent of the sunspot number, cc = 0.13 ± 0.05). Coronal jets affect switchbacks only indirectly via modulation of the solar wind speed. Multi-spacecraft consensus confirms that a stable, Alfvénicity-dependent process governs switchback variability, rather than episodic surface drivers. In addition, these results are robust to the deflection threshold of switchbacks. These findings impose quantitative constraints on theories of solar-wind turbulence and the transport of magnetic energy from the Sun to interplanetary space.

When the interplanetary magnetic field (IMF) changes towards its final orientation, induction within the Moon enhances the magnetic field beneath the lunar surface but outside the conductive interior. This enhanced magnetic field compresses the solar wind near the lunar terminator, forming limb compression structures. Using three-dimensional, time-dependent magnetohydrodynamic simulations, we systematically explore how the lunar core radius, core conductivity, and the amplitude of the IMF variation influence these limb compression structures. Our findings demonstrate that a larger core radius, higher core conductivity, and a larger magnetic field change result in a stronger induced magnetic field and more pronounced limb compression. However, when core conductivity exceeds 0.1 S m(-1), further increases in the core conductivity have minimal impact. These simulation results serve as a forward-modelling study that lays the groundwork for future efforts to constrain the lunar interior stratification under conditions of external magnetic field perturbations by combining numerical modeling with spacecraft observations.