Image: Strong solar flare

This Feb. 4, 2026, image from NASA's Solar Dynamics Observatory (SDO) captures a strong solar flare erupting from the star. Solar flares are powerful bursts of energy that can, along with other types of solar eruptions, impact radio communications, electric power grids, navigation signals, and pose risks to spacecraft and astronauts. The flare pictured was classified as an X4.2 flare. X-class denotes the most intense flares, while the number provides more information about its strength.