Movie courtesy of NASA/Goddard Space Flight Center - Conceptual Image Lab.
Geomagnetic Substorm Triggered by CME from Sun
This movie opens with a close-up view of the Sun. The solar wind streams outward into interplanetary space. Our view shifts to Earth which is surrounded by the planet's magnetosphere (magnetic field lines are shown in blue). A coronal mass ejection (CME) from the Sun arrives from the left, buffeting and warping Earth's magnetosphere. Some solar magnetic field lines (shown in orange) link up with Earth's magnetic field.
As we zoom in on Earth, we see that some loops in Earth's magnetic field on the side away from the Sun get compressed and pinched off. This process, called magnetic reconnection, releases bursts of particles which stream towards Earth along magnetic field lines. The particles in these "geomagnetic substorms" collide with gas molecules in Earth's upper atmosphere. The collisions release energy, which we see as the glowing lights of the aurora (Southern and Northern Lights).
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