Magnetic reconnection has recently emerged as an important process in the Martian space environment. In contrast to Earth, Mars lacks a global intrinsic dipole field and possesses an induced magnetosphere shaped by solar-wind interaction with the ionosphere, localized crustal magnetic anomalies, and abundant planetary heavy ions. Recent measurements from Mars Global Surveyor, Mars Express, MAVEN, and Tianwen-1 have revealed reconnection signatures in several distinct regions, including the dayside induced magnetosphere, the induced magnetotail, the crustal-field mini-magnetospheres, and the upper ionosphere. These reconnection signatures include Hall-like magnetic perturbations, multi-species ion outflows, magnetic flux ropes, reconnection fronts, and electron pitch-angle changes indicative of magnetic topology reconfiguration. This review synthesizes recent observational and theoretical progress on Martian magnetic reconnection and discusses its implications for magnetospheric structure, plasma energization, auroral activity, and atmospheric ion escape. Particular attention is given to the effects of interplanetary magnetic field variability, heavy-ion composition, and ionospheric collisionality, which distinguish reconnection at Mars from more familiar terrestrial cases. Although existing observations show that reconnection is a recurrent and potentially important component of Mars–solar-wind coupling, its global occurrence rate, spatial extent, and long-term atmospheric impact remain poorly constrained. Future coordinated multi-spacecraft measurements and multi-scale simulations will be critical for linking local reconnection physics to global plasma transport and atmospheric evolution.
The influence of the zonal harmonics J4 on the positions and stability of the out-of-plane equilibrium points of an infinitesimal mass, in the framework of the photogravitational elliptic restricted three-body problem (ER3BP), has been investigated. The positions change with an increase in the oblateness up to zonal harmonics J4, radiation pressure, eccentricity and semi-major axis of the orbit. The positions and stability of the out-of-plane points are affected by the parameters involved. The effect of these parameters on the positions of the out-of-plane equilibrium points is examined numerically both for the binary system 61 CYGNI and for arbitrary values. The results obtained from this study can be applied to different methods of celestial mechanics, with application to the planetary system.
Abstract Catastrophic earthquakes (EQs) (M ≥ 8) and global ionospheric plasma variations exhibit unexpected planetary orbital periodicities that cannot be explained by known (geo)physical processes. In this study, we identify a robust pre seismic signature in the Total Electron Content (TEC) of the ionosphere that precedes major EQs by up to two months. This finding leads to a novel forecasting method for large magnitude events, providing a significant advance warning window. We propose that the underlying causal triggering mechanism for such correlated phenomena fits-in the scenario of gravitational focusing of galactic dark matter (DM) streams by the solar system bodies. In this framework, Earth based observational tools like the global GPS network can serve a dual role: monitoring terrestrial dynamics and acting as possible sensitive detectors for DM. We demonstrate how continuous GPS recordings can be exploited to project, in real time, the likely timing and location of major seismic events. This interdisciplinary approach provides a novel route to enhance the reliability of catastrophic EQ forecasting. Concurrently, it offers a new method for the direct detection of the dark sector following otherwise unexpected planetary dependencies. While the Axion Quark Nugget (AQN) framework provides an interesting basis for these results, the identified precursors remain model-independent.
The linear and nonlinear propagation of dust–acoustic waves in an inhomogeneous dusty plasma with nonthermal electrons and ions is investigated. The effects of electron and ion nonthermality, equilibrium plasma densities, dust charge, and temperature ratio are included. By applying the reductive perturbation method, we derive a damped Korteweg–de Vries equation governing the nonlinear evolution of the dust-acoustic mode. The resulting equation and its analytical solution are examined in detail. The soliton amplitude exhibits a non-monotonic dependence on the nonthermal parameters, attaining a maximum at intermediate values as a result of the competition between nonlinearity and dispersion. The results emphasize the joint influence of plasma inhomogeneity, nonthermal populations, and dust charging on dust–acoustic wave dynamics, and they may be tested against contemporary experimental observations in complex plasmas. In several limiting cases, the present results reduce to previously reported models, and the findings are applicable to both laboratory and space dusty plasma studies.
Seismic activity can impact different layers of the Earth’s atmosphere; however, our understanding of lithosphere-atmosphere-ionosphere coupling mechanism still remains limited and is challenging. Previous studies predominantly feature seismo-ionospheric changes associated with large earthquakes/tsunamis. Seismic-induced changes in the Mesosphere-Lower Thermosphere (MLT) region have not been properly addressed and are limited to a few reports. We present, here, rare observations of anomalies in the temperature and airglow of the MLT region using Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on board Thermosphere Ionosphere Mesosphere Energetics Dynamics (TIMED) spacecraft measurements for 2025 Mw 8.8 Kamchatka Peninsula Earthquake. Beginning with the Mainshock at 23:24:52 UT on 29 July 2025, over a hundred aftershocks (with a majority exceeding intensity-scale of Mw 5.0) occurred near Petropavlovsk-Kamchatsky and Severo-Kuril’sk in Russia and activity continued beyond 31 July. We found an increase in temperature in the 73–83 km range on 30 July. However, the temperature decreased in the 87–97 km range on 30 and 31 July. Further, we noted a minor increase and distinct decrease in the volume emission rate of OH airglow on 30 July over the height range of 76–82 km and 83–90 km, respectively. Comparatively, significant decrease in OH airglow was seen on 31 July in the 81–96 km height range. Unusual gravity wave (GW) activity was, also, noted with predominant presence of waves with vertical wavelength of 18 km. Similar anomalous temperature enhancement and pronounced decrease in OH airglow was seen during the 2011 Mw 9.1 Tohoku-Oki earthquake as well.
