From solar wind to cometary dust: Curation and microanalysis of sample return
Abstract
The coming decade has the potential to deliver ground truth evidence for a number of important unanswered cosmochemical questions, with sample return missions capturing solar wind and particles of interstellar, cometary and asteroidal origin. The yield of information that these samples can offer is unquestionable yet some fundamental issues must be resolved before their imminent return. Two immediate problems are those of curation and small sample size, arising because all the missions will return only micrometre or smaller material (implanted or embedded into dedicated capture cells). Furthermore coincidental capture of interplanetary dust particles will occur on the exposed surfaces of the Genesis spacecraft. So the first non-trivial task is to develop appropriate extraction techniques. We have applied a novel approach of using a laser ablation extraction system (developed for liberating implanted solar wind oxygen from the Genesis mission collectors) to slice the aerogel containing embedded particles from a light-gas-gun shot. For the intact materials returned by Stardust and Muses-C there are numerous sophisticated microanalysis techniques now available to routinely obtain chemical data on the nanometre scale. Yet many may damage vulnerable volatile-rich materials, or produce surface contamination if employed at too early a stage. Therefore initial assessment of the most appropriate analytical protocols for each grain is essential. Preliminary studies suggest that Raman microscopy and a new X- ray source technology have the potential to be powerful tools in the preliminary characterisation of captured grains. As the countdown for return continues there are many more challenges that await and must be resolved, not least the microanalysis techniques are often at the cutting edge of technological development requiring a commitment to continued development and support.
- Publication:
-
34th COSPAR Scientific Assembly
- Pub Date:
- 2002
- Bibcode:
- 2002cosp...34E2182G