Graphite Whiskers in CV3 Meteorites
- 4 April 2008
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 320 (5872), 91-93
- https://doi.org/10.1126/science.1153578
Abstract
Graphite whiskers (GWs), an allotrope of carbon that has been proposed to occur in space, have been discovered in three CV-type carbonaceous chondrites via Raman imaging and electron microscopy. The GWs are associated with high-temperature calcium-aluminum inclusion (CAI) rims and interiors, with the rim of a dark inclusion, and within an inclusion inside an unusual chondrule that bears mineralogy and texture indicative of high-temperature processing. Current understanding of CAI formation places their condensation, and that of associated GWs, relatively close to the Sun and early in the condensation sequence of protoplanetary disk materials. If this is the case, then it is a possibility that GWs are expelled from any young solar system early in its history, thus populating interstellar space with diffuse GWs. Graphite whiskers have been postulated to play a role in the near-infrared (near-IR) dimming of type Ia supernovae, as well as in the thermalization of both the cosmic IR and microwave background and in galactic center dimming between 3 and 9 micrometers. Our observations, along with the further possibility that GWs could be manufactured during supernovae, suggest that GWs may have substantial effects in observational astronomy.Keywords
This publication has 33 references indexed in Scilit:
- MICRO- AND NANOSCALE GRAPHITE CONES AND TUBES FROM HACKMAN VALLEY, KOLA PENINSULA, RUSSIAThe Canadian Mineralogist, 2007
- Late-stage, high-temperature processesing in the Allende meteorite: Record from Ca,Fe-rich silicate rims around dark inclusionsAmerican Mineralogist: Journal of Earth and Planetary Materials, 2004
- Naturally occurring graphite conesCarbon, 2003
- Graphite Polyhedral CrystalsScience, 2000
- Carbon in the UniverseScience, 1998
- X-rays and Fluctuating X-Winds from ProtostarsScience, 1997
- Mineralogical and chemical modification of components in CV3 chondrites: Nebular or asteroidal processing?Meteoritics, 1995
- Conical, helically wound, graphite whiskers: a limiting member of the “fullerenes”?Journal of Crystal Growth, 1992
- Dark inclusions in Allende, Leoville, and Vigarano: Evidence for nebular oxidation of CV3 constituentsGeochimica et Cosmochimica Acta, 1990
- Condensation in the primitive solar nebulaGeochimica et Cosmochimica Acta, 1972