Development and testing of quartz crystal microbalances for missions to measure particle fluxes from minor solar system bodies
Abstract
An instrument is being developed to measure the mass flux and size distribution of particles striking a spacecraft operating in the vicinity of airless minor solar system bodies including asteroids, small moons, and comets. We are developing and testing quartz crystal microbalances (QCMs) with robust particle capture coatings coupled with advanced oscillator electronics. The instrument is an extension the QCMs that are part of the Grain Impact Analyzer and Dust Accumulator (GIADA) instrument that will be carried aboard the European Space Agency (ESA) Rosetta Spacecraft. Particle capture coatings are required that will survive the interplanetary environment for long periods. The coatings should provide effective particle capture and coupling to a QCM to allow mass measurements during rendezvous encounters. We are using thin aerogel layers for particle capture since aerogel consists of a very low density (99% void volume) web of rigidly connected, sub-micron silica fibers. Sophisticated oscillator circuits are required to oscillate a QCM with a thick particle capture coating. Previously we reported on measurements of the electro-mechanical properties of thick (100 micrometer) layers of aerogel bonded to QCMs. In this work we report the results of firing small (100-500 micrometer) grains at aerogel-coated QCMs using a light gas gun at the University of Florida. The efficiency of particle capture by the aerogel layer as a function of particle size, velocity, and material composition was measured. The results will help guide the design of a second generation of aerosol capture coatings for QCMs.
- Publication:
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EGS - AGU - EUG Joint Assembly
- Pub Date:
- April 2003
- Bibcode:
- 2003EAEJA.....4478S