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Why does Earth’s magnetosphere extend farther on the nightside than on the Sun-facing side?

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Earth’s magnetosphere is shaped by its interaction with the solar wind, a collisionless plasma consisting primarily of electrons and protons flowing from the Sun.12

On the Sun-facing side (dayside), the pressure of the solar wind compresses the Earth’s magnetic field, confining the magnetosphere to a boundary known as the magnetopause, located at approximately 10 Earth radii.314

In contrast, on the nightside, the forces associated with the magnetic field and the solar wind act in parallel. This alignment allows the magnetosphere to stretch into an elongated magnetotail that extends far beyond the planet, reaching distances that may exceed 1,000 Earth radii. Consequently, the overall shape of the magnetosphere resembles a comet, with the Earth situated near the head and the magnetotail trailing downstream, away from the Sun.3412