Electrogravitics is claimed to be an unconventional type of effect or anti-gravity propulsion created by an electric field's effect on a mass. The name was coined in the 1920s by the discoverer of the effect, Thomas Townsend Brown, who spent most of his life trying to develop it and sell it as a propulsion system. Through Brown's promotion of the idea it was researched for a short while by aerospace companies in the 1950s. Electrogravitics is popular with conspiracy theorists with claims that it is powering flying saucers and the B-2 Stealth Bomber.