Helioseismic and Magnetic Imager (HMI)

The Helioseismic and Magnetic Imager (HMI) is a scientific instrument on NASA’s Solar Dynamics Observatory that studies the Sun. It observes the Sun’s surface to measure its magnetic fields and detect waves traveling inside the Sun. These measurements help scientists understand solar activity, like sunspots and solar flares, and predict space weather that can affect Earth’s technology. By continuously monitoring the Sun, HMI provides critical data to advance our knowledge of solar processes and improve forecasting of solar-related phenomena.