The Juno Waves instrument “listened” to the radio emissions from Jupiter’s immense magnetic field to find their precise locations.

By listening to the rain of electrons flowing onto Jupiter from its intensely volcanic moon Io, researchers using NASA’s Juno spacecraft have found what triggers the powerful radio emissions within the monster planet’s gigantic magnetic field. The new result sheds light on the behavior of the enormous magnetic fields generated by gas-giant planets like Jupiter.

Jupiter has the largest, most powerful magnetic field of all the planets in our solar system, with a strength at its source about 20000 times stronger than Earth’s. It is buffeted by the solar wind, a stream of electrically charged particles and magnetic fields constantly blowing from the Sun. Depending on how hard the solar wind blows, Jupiter’s magnetic field can extend outward as much as two million miles (3.2 million kilometers) toward the Sun and stretch more than 600 million miles (over 965 million kilometers) away from the Sun, as far as Saturn’s orbit.