The Waves instrument will measure radio and plasma waves in Jupiter’s magnetosphere, helping us understand the interactions between the magnetic field, the atmosphere and the magnetosphere. Waves will also pay particular attention to activity associated with auroras.

The magnetosphere, an enormous bubble created by Jupiter’s magnetic field, traps plasma – an electrically charged gas. Activity and other features in the plasma trigger waves that only an instrument like Waves can detect. The plasma fills the magnetosphere. Because plasma conducts electricity, it behaves like a giant circuit, connecting one region with another. Activity in one end of the magnetosphere can therefore be felt somewhere else, allowing Juno to monitor the entire magnetosphere.

Radio and plasma waves surround all the outer planets, so previous missions that have explored the gas giants were equipped with similar instruments. J Juno's Waves instrument consists of two sensors; one detects the electric component of radio and plasma waves while the other is sensitive to just the magnetic component of plasma waves. The first sensor, called an electric dipole antenna, is a V-shaped antenna, four meters from tip to tip -- similar to the rabbit-ear antennas that were once common on TVs. The magnetic antenna -- called a magnetic search coil -- consists of a coil of fine wire wrapped 10,000 times around a 15- centimeter-long core. The search coil measures magnetic fluctuations in the audio frequency range.

Dr. William Kurth of the University of Iowa leads the Waves team, and the University of Iowa provides the instrument.