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Sweeping over the poles at altitudes of up to 32,000 miles, scientists' best look yet at the magnetosphere, the region of space under the invisible influence of Earth's magnetic field, is coming from a new satellite called POLAR.

Sweeping over the poles at altitudes of up to 32,000 miles, a new satellite called POLAR is giving scientists their best look yet at the magnetosphere, the region of space under the invisible influence of Earth's magnetic field.