Heliophysics and Space Weather

Heliophysics surveys the Sun’s plasma, magnetic and radiative environment and its influence on the near-Earth space. Solar processes, from convective motions in the interior to eruptive phenomena in the atmosphere, drive particles and fields into the heliosphere. Streams of charged particles and embedded magnetic flux form the solar wind, which interacts with Earth’s magnetosphere to produce geomagnetic storms, auroras and radiation-belt enhancements. Coupling through field-aligned currents, wave–particle interactions and induced electric fields shapes the ionospheric electron density, perturbing radio propagation, satellite operations and GNSS positioning. Space-weather events range from rapid X-ray bursts that modify the lower ionosphere to coronal mass ejections that compress the magnetosphere and inject energetic particles. Advances in multi-point spacecraft, ground-based radar and global models now permit increasingly accurate specification and forecasting of conditions that affect power grids, communication networks and navigation systems worldwide.

Research from Nature Portfolio

Measurements by the Parker Solar Probe have revealed that fast solar wind streams originate via continual interchange reconnection at the edges of coronal holes. Supergranular magnetic patterns remain imprinted in accelerated plasma, and bursty ion energy spectra extend beyond 100 keV, confirming collisionless reconnection as a viable wind-acceleration mechanism. Ultra-high-resolution extreme-ultraviolet imaging from a near-Sun mission has for the first time resolved persistent null-point reconnection at sub-kilometre scales in the low corona. Both gentle, steady outflows and short explosive phases produce fan-spine structures and spiral jets, demonstrating how small-scale reconnection contributes to coronal heating and mass supply to open field lines. Complementing these in situ and remote observations, multi-GNSS studies have shown that combining BeiDou, Galileo, GLONASS and GPS measurements quadruples the number of ionospheric piercing points, enabling high-resolution global maps of total electron content that improve model validation and space-weather monitoring.

Heliophysics and Space Weather publication trend

The graph below shows the total number of articles in heliophysics and space weather across all publications each year (not limited to Nature Index journals).

Technical terms

Heliophysics: The interdisciplinary study of the Sun’s plasma, magnetic field and radiative environment, and their interactions with planetary space environments.

Solar wind: A continuous outflow of ionised gas carrying frozen-in magnetic fields from the solar corona into interplanetary space.

Coronal mass ejection (CME): A large-scale eruption of plasma and magnetic flux from the solar corona that propagates through the heliosphere and may drive geomagnetic disturbances.

Magnetic reconnection: A process in which oppositely directed magnetic field lines break and rejoin, converting magnetic energy into plasma heating, acceleration and bulk flows.

Interchange reconnection: A specific form of reconnection at coronal-hole boundaries that exchanges closed and open field lines, releasing energy and accelerating solar wind plasma.

Ring current: A westward-drifting toroidal current of energetic ions and electrons around Earth that intensifies during geomagnetic storms and depresses the surface magnetic field.

Total Electron Content (TEC): The integrated number of free electrons along a satellite-to-ground path through the ionosphere, expressed in TEC units (1 TECU = 10¹⁶ electrons m⁻²).

References

1. Interchange reconnection as the source of the fast solar wind within coronal holes. Nature (2023).
2. Ultra-high-resolution observations of persistent null-point reconnection in the solar corona. Nature Communications (2023).
3. Global Ionospheric Modelling using Multi-GNSS: BeiDou, Galileo, GLONASS and GPS. Scientific Reports (2016).
4. Impacts of Extreme Ultraviolet Late Phase of the Solar Flare on Ionospheric Electrodynamics. The Astrophysical Journal Letters (2024).
5. Complete Global Total Electron Content Map Dataset based on a Video Imputation Algorithm VISTA. Scientific Data (2023).
6. Forecasting Global Ionospheric TEC Using Deep Learning Approach. Space Weather (2020).