Earth’s magnetic field

Magnetometer

Aurora is the sky’s reply when a solar storm shakes Earth’s magnetic field. These charts are that shaking, live, at two latitudes: Lofoten in northern Norway, where even a modest storm can light the sky, and the Veluwe in the Netherlands, which only moves when the disturbance reaches farther south. Watch Horizontal most closely — a sudden drop or a train of oscillations is a storm arriving. Flat lines mean a quiet magnetosphere.