heliophysics

Heliophysics is the science of the Sun and its influence on the solar system, including the physical processes that originate in the solar interior and atmosphere and propagate through the heliosphere to affect planets, moons, and space weather. It encompasses solar physics, space plasma physics, and planetary space environments, and seeks to understand how magnetic fields, plasma, and energetic particles drive solar activity and its coupling to planetary environments.

Its main areas include solar interior dynamics and magnetic activity; the solar atmosphere and coronal heating; the solar wind and interplanetary magnetic field; heliospheric structure, turbulence, and magnetic reconnection; solar storms such as flares and coronal mass ejections; energetic particles and cosmic ray modulation; and the interactions of solar output with planetary magnetospheres, atmospheres, and rings.

Methods in heliophysics combine observations and theory. Observations from space missions such as SOHO, SDO, Parker Solar Probe, and Solar Orbiter, as well as ground-based facilities like the Daniel K. Inouye Solar Telescope, provide data across multiple wavelengths and in situ measurements. Theoretical and computational modeling, including magnetohydrodynamics and kinetic plasma physics, complements data analysis and supports space weather forecasting and interpretation of phenomena.

Significance lies in its ability to inform space weather prediction, protect satellites, astronauts, and power systems, and advance understanding of fundamental plasma processes that occur in many astrophysical settings. The field emphasizes an integrated approach, linking the Sun’s internal dynamics to the broader heliospheric environment.

History notes that the term heliophysics gained prominence to reflect this integrated framework, with international programs supporting multidisciplinary research across observation, theory, and modeling.