The WAVES instrument is basically a radio.
It tunes to frequencies all the way from 50 Hz,
which is near the bottom of the audio frequency range,
up to above 40 mHz,
which is above the limit of the radio emissions that Jupiter generates.
The WAVES instrument has two sensors.
One is designed to measure the electric field component of these waves
and it looks like a pair of rabbit-ear antennas
that you might have had on a TV when you were a kid.
Except these are about ten feet long.
The other sensor is a much smaller device,
it's about ten inches long,
and it's basically a coil of wire.
It has about ten thousand turns on it
and it's designed to measure the magnetic fluctuations of waves.
So these two sensors are used by the receivers
to study the various phenomenon,
particularly in Jupiter's polar magnetosphere.
For example, the maximum frequency of the radio emissions that we detect
told us what the magnetic field strength was
in the magnetosphere of Jupiter.
Long before any spacecraft arrived,
Juno was designed to actually to go to another planet
and make the first measurements of
an extra-terrestrial auroral region in great detail.
So I think we learn about ourselves
by studying other environments in the universe.