Details

Autor(en) / Beteiligte

• Graham, G. A.
• Teslich, N.
• Dai, Z. R.
• Bradley, J. P.
• Kearsley, A. T.
• Hörz, F.

Titel

Focused ion beam recovery of hypervelocity impact residue in experimental craters on metallic foils

Ist Teil von

• Meteoritics & planetary science, 2006-02, Vol.41 (2), p.159-165

Ort / Verlag

Oxford, UK: Blackwell Publishing Ltd

Erscheinungsjahr

2006

Quelle

Wiley Online Library

Beschreibungen/Notizen

• — The Stardust sample return capsule returned to Earth in January 2006 with primitive debris collected from comet 81P/Wild‐2 during the flyby encounter in 2004. In addition to the cometary particles embedded in low‐density silica aerogel, there are microcraters preserved in the aluminum foils (1100 series; 100 μm thick) that are wrapped around the sample tray assembly. Soda lime spheres (˜49 μm in diameter) have been accelerated with a light gas gun into flight‐grade aluminum foils at 6.35 km s−1 to simulate the capture of cometary debris. The experimental craters have been analyzed using scanning electron microscopy (SEM) and X‐ray energy dispersive spectroscopy (EDX) to locate and characterize remants of the projectile material remaining within the craters. In addition, ion beam‐induced secondary electron imaging has proven particularly useful in identifying areas within the craters that contain residue material. Finally, high‐precision focused ion beam (FIB) milling has been used to isolate and then extract an individual melt residue droplet from the interior wall of an impact. This has enabled further detailed elemental characterization that is free from the background contamination of the aluminum foil substrate. The ability to recover “pure” melt residues using FIB will significantly extend the interpretations of the residue chemistry preserved in the aluminum foils returned by Stardust.