308 Polyxo: ISO–SWS spectrum up to 26 micron ^*,**

¹ INAF – Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio Catone (Roma), Italy e-mail: dotto@mporzio.astro.it
² LESIA – Observatoire de Paris, 5 place J. Janssen, 92195 Meudon Cedex, France
³ INAF – Osservatorio Astronomico di Capodimonte, via Moiariello 16, 80131 Napoli, Italy
⁴ Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, 85748 Garching, Germany
⁵ Observatório Nacional/MCT, Coordenação de Astronomia e Astrofísica – CAA, 20921-400 Rio de Janeiro, Brazil

Received: 3 June 2004
Accepted: 13 July 2004

Abstract

Infrared spectroscopic observations of the asteroid 308 Polyxo have been carried out by the Infrared Space Observatory (ISO) with the Short Wavelength Spectrometer (SWS) in the spectral region between 7 and 26 μm. The Standard Thermal Model and the Thermophysical Model have been applied to the obtained data in order to model the thermal continuum. Sub-solar and black-body temperatures also have been derived. The obtained spectrum has been compared with laboratory spectra of minerals and meteorites available in the literature. Moreover, we performed new measurements to obtain infrared spectra of the Tagish Lake meteorite, recognized as the best analog of primitive D-type asteroids. A tentative spectral similarity with the Ornans meteorite is suggested, while we cannot confirm, in the considered wavelength range, the analogy with the Tagish Lake meteorite.