NEAR-INFRARED SPECTROSCOPY OF DARK ASTEROIDS

Near-infrared (J, H and K bands) spectra of nine dark asteroids (chose n among a sample of supposed primitive objects between C and D classes ) have been obtained at the Mauna Kea Observatory (Hawaii) with the 2. 2-m telescope using KSPEC as spectrograph. The aim of this work was to search for evidence of the presence of organic materials in these obj ects as found in other planetary bodies as 5145 Pholus, and in some co metary nuclei. A careful analysis of the data has revealed flat or sli ghtly redder spectra than the solar one for all observed asteroids. No evidence of distinct absorption features was found. (C) 1994 Academic Press. Inc.