Possible Gems and Ultra-Fine Grained Polyphase Units in Comet Wild 2.GEMS and ultrafine grained polyphase units (UFG-PU) in anhydrous IDPs are probably some of the most primitive materials in the solar system. UFG-PUs contain nanocrystalline silicates, oxides, metals and sulfides. GEMS are rounded approximately 100 nm across amorphous silicates containing embedded iron-nickel metal grains and sulfides. GEMS are one of the most abundant constituents in some anhydrous CPIDPs, often accounting for half the material or more. When NASA's Stardust mission returned with samples from comet Wild 2 in 2006, it was thought that UFG-PUs and GEMS would be among the most abundant materials found. However, possibly because of heating during the capture process in aerogel, neither GEMS nor UFG-PUs have been clearly found.
Document ID
20160002399
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
Gainsforth, Z. (California Univ. Berkeley, CA, United States)
Butterworth, A. L. (California Univ. Berkeley, CA, United States)
Jilly-Rehak, C. E. (California Univ. Berkeley, CA, United States)
Westphal, A. J. (California Univ. Berkeley, CA, United States)
Brownlee, D. E. (Washington Univ. Seattle, WA, United States)
Joswiak, D. (Washington Univ. Seattle, WA, United States)
Ogliore, R. C. (Saint Louis Univ. MO, United States)
Zolensky, M. E. (NASA Johnson Space Center Houston, TX, United States)
Bechtel, H. A. (California Univ. Berkeley, CA, United States)
Ebel, D. S. (American Museum of Natural History New York, NY, United States)
Huss, G. R. (Hawaii Univ. at Manoa Honolulu, HI, United States)
Sandford, S. A. (NASA Ames Research Center Moffett Field, CA, United States)
White, A. J. (American Museum of Natural History New York, NY, United States)