Scanning Electron-Microscopes and Other Beam Instruments for Spaceflight

Abstract

SEMPA (Scanning Electron Microscope and Particle Analyser) is-a newly developed spacecraft instrument, miniaturized from familiar laboratory instruments for NASA's Comet Rendezvous/Asteroid Flyby mission in the '90's. SEMPA will determine elemental composition, shape, morphology, and mineralogy of individual dust particles and charaterize the flux. Spaceflight requirements demanded tradeoffs against current instrument performance and design concepts to adopt to the space environment, minimize weight and power consumption, and increase the maintenance-free lifetime. Other instruments that utilize in-site excitation of "rocky" samples are being designed by U.S., Soviet, and European scientists for future space missions. Under consideration is excitation with ion beams, laser beams, white light, pulsed neutron generators, x-ray generators, and particle accelerations.