OPERATION OF LIQUID-METAL FIELD-ION EMITTERS UNDER MICROGRAVITY

Ion-beam technology has found a wide spectrum of applications in space exploration, ranging from electric propulsion and spacecraft-potentia l control to the mass analysis of matter on planetary missions, and mo st recently in the development of a materials-analysis tool for use on -board space stations. So far, all instruments employing ion-beam emis sion have relied on gas-fed, Kaufmann-type ion sources. This paper rep orts the development of a 'Liquid-Metal Ion Source' (LMIS) for space a pplications which, among other advantages, reduces both power and mass requirements by a factor of 10 compared with conventional systems. Re sults from the first three systems exploiting an LMIS are also briefly discussed.