Earth's Magnetic Field

planet Earth · magnetism · space protection

Made by molten metal. Deep inside Earth, the outer core is so hot that iron and nickel melt into liquid. As this liquid swirls and moves around, it generates electricity, which creates our planet's magnetic field, kind of like a battery that never runs out.

Shields from the Sun. Earth's magnetic field acts as an invisible shield that protects us from the solar wind, a stream of dangerous charged particles constantly blasting toward Earth from the Sun. Without this shield, these particles could harm life on our planet.

Extends far into space. The magnetic field isn't just around Earth like a thin coating. It stretches thousands of miles out into space, creating a bubble called the magnetosphere that protects a huge region around our planet.

Guides a compass needle. The magnetic field is why compass needles point north and south. The needle aligns with the invisible lines of magnetic force flowing from the south magnetic pole to the north magnetic pole.

Powered by Earth's heat. The molten iron and nickel in the outer core move because heat from even deeper in Earth is constantly trying to escape. This endless motion is called a geodynamo, and it's what keeps our magnetic field running 24/7.