Electrodes, ion-propulsion test, R.H. Goddard

American rocket pioneer Robert Goddard (1882-1945) used these electrodes between 1924 and 1928 in his experiments to determine the feasibility of ion propulsion for space travel. Ion engines, in which electrically charged particles of atoms are discharged, produce extremely high exhaust velocities. Experiments in space with ion propulsion first took place in 1964.

Mrs. Goddard gave this artifact to the Smithsonian in 1965 as part of a set of laboratory glassware from her husband's pioneering ion-propulsion experiments.