EDP Sciences
Free access
Issue
A&A
Volume 416, Number 3, March IV 2004
Page(s) 983 - 990
Section Interstellar and circumstellar matter
DOI http://dx.doi.org/10.1051/0004-6361:20034526


A&A 416, 983-990 (2004)
DOI: 10.1051/0004-6361:20034526

FTIR and Raman analyses of the Tagish Lake meteorite: Relationship with the aliphatic hydrocarbons observed in the Diffuse Interstellar Medium

G. Matrajt1, J. Borg1, P. I. Raynal1, Z. Djouadi1, L. d'Hendecourt1, G. Flynn2 and D. Deboffle1

1  IAS, Bât. 121, Université Paris-Sud, 91405 Orsay Cedex, France
2  Department of Physics, SUNY-Plattsburgh, Plattsburgh NY, 12901, USA

(Received 16 October 2003 / Accepted 27 November 2003)

Abstract
Using FTIR and Raman microspectroscopies we have analysed 6 fragments of the Tagish Lake meteorite. The data obtained show that all the fragments belong to the carbonate-rich lithology, where an organic material, including a highly disordered macromolecular carbonaceous component is found. The FTIR approach shows that part of the organic material present in Tagish Lake is aliphatic. The Raman approach shows that there is also highly disordered polyaromatic organic material, which is abundant. Furthermore, the comparison of Raman data of Tagish Lake to other carbonaceous chondrites (CI, CM2, CR2) shows that the carbon in Tagish Lake is different, supporting the assertion that this meteorite is a unique and new type of carbonaceous chondrite. The comparison of the aliphatic hydrocarbon FTIR data found in the Tagish Lake meteorite with the aliphatic hydrocarbon IR data of the carbonaceous chondrites Orgueil and Murchison and with the diffuse Interstellar Medium (ISM) shows that they are different, in that the Tagish Lake meteorite has longer aliphatic chains.


Key words: meteors, meteoroids -- techniques: spectroscopic -- methods: analytical -- ISM: molecules -- astrochemistry

Offprint request: G. Matrajt, graciela.matrajt@ias.u-psud.fr




© ESO 2004