Within the framework of an ESO large program on Centaurs and TNOs, we present spectroscopic results obtained through visible and near-infrared observations performed with FORS1 and ISAAC at the Very Large Telescope (VLT) ESO - Cerro Paranal (Chile). Up today we obtained visible spectra for 12 objects. For 9 out of them we obtained also near infrared spectra in the range 1.1-2.45 micron. The visible spectra are mostly featureless and show slopes from neutral to red. Two objects, 2000 EB173 and 2000 GN171, show wide absorption dips centered around 600nm & 745nm and 700nm respectively, which resemble the absorptions due to aqueous alteration of the surface materials. The near infrared spectra have been obtained in the J, H and K bands. For some of them, we found indications of water ice absorptions at 1.5 and 2 micron at different level of detectability. Models have been computed using a radiative transfer code with a simple geographical mixture of organics, minerals and ices in order to have an indication of the possible surface composition. The obtained results will be presented and discussed.
ESO Large Program: Results from Visible and Infrared spectroscopy of Centaurs and TNOs
LAZZARIN, MONICA;
2002
Abstract
Within the framework of an ESO large program on Centaurs and TNOs, we present spectroscopic results obtained through visible and near-infrared observations performed with FORS1 and ISAAC at the Very Large Telescope (VLT) ESO - Cerro Paranal (Chile). Up today we obtained visible spectra for 12 objects. For 9 out of them we obtained also near infrared spectra in the range 1.1-2.45 micron. The visible spectra are mostly featureless and show slopes from neutral to red. Two objects, 2000 EB173 and 2000 GN171, show wide absorption dips centered around 600nm & 745nm and 700nm respectively, which resemble the absorptions due to aqueous alteration of the surface materials. The near infrared spectra have been obtained in the J, H and K bands. For some of them, we found indications of water ice absorptions at 1.5 and 2 micron at different level of detectability. Models have been computed using a radiative transfer code with a simple geographical mixture of organics, minerals and ices in order to have an indication of the possible surface composition. The obtained results will be presented and discussed.Pubblicazioni consigliate
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