The Theremin is an electronic musical instrument that is played without physical contact.

The Thereminist, or performer, stands in front of the instrument and moves their hands around two metal antennas that create an electromagnetic field. The pitch is controlled by moving the hands near a vertical antenna, and the volume is controlled by moving the hands up or down over a looped antenna.
The theremin was invented in 1919 by Russian physicist Leon Theremin. It was originally known as the ætherphone, thereminophone, or termenvox. The theremin is known for its use in science fiction films and its eerie timbre that sounds like a descending alien spacecraft.