Solar storms are driven by activity on the Sun that releases energy and material into space, which can interact with Earth’s space environment. The core causes are magnetic processes on the Sun and the way the Sun’s eruptions travel through space. Direct answer

• Magnetic energy build-up on the Sun: The Sun’s surface and atmosphere are threaded with intricate magnetic fields. In active regions—often around sunspots—these fields become twisted and stressed as the Sun rotates. This stored magnetic energy can become unstable and release energy suddenly. This release is typically due to magnetic reconnection, where twisted magnetic field lines break and rejoin in a lower-energy configuration, ejecting plasma and radiation into space.

• Solar flares and coronal mass ejections (CMEs): Magnetic reconnection powers solar flares, which are intense bursts of electromagnetic radiation from the Sun’s atmosphere. Flares are frequently (though not always) associated with CMEs, which are large expulsions of plasma and magnetic field into interplanetary space. CMEs can drive disturbances as they propagate and interact with the solar wind.

• Interplanetary travel of eruptions: Once formed, CMEs and associated particles travel through the heliosphere. If a CME or its shock front reaches Earth, it can compress and disturb Earth’s magnetosphere, leading to geomagnetic storms. Energetic particles from solar storms can also arrive and cause radiation hazards in space and at high altitudes.

• Space weather effects near Earth: The interaction of solar eruptions with Earth’s magnetic field can cause a range of effects, including disturbances in the ionosphere that affect radio communications and navigation, satellite perturbations, and sometimes visible auroras at high latitudes. The magnetosphere and ionosphere act as protective barriers but can be temporarily overwhelmed by strong events.

Context and sources

• NASA and NOAA describe the underlying mechanisms as magnetic reconnection on the Sun, producing flares and CMEs that propagate outward and can impact Earth’s space environment.

• Solar flares are tied to energy release via magnetic reconnection, often occurring in active regions and near sunspots, and can accompany CMEs that enhance space weather effects.

• Space weather centers monitor and describe the potential impacts of geomagnetic storms, solar radiation storms, and related phenomena on satellites, aviation, and communications.

If you’d like, I can tailor this to a particular aspect (e.g., how CMEs interact with Earth’s magnetosphere, or how to interpret space weather alerts) or provide a simple diagram-style explanation of the sequence from magnetic stress to geomagnetic storm.