Interstellar ices studied with the Infrared Space Observatory

The Infrared Space Observatory (ISO) was launched by the European Space Agency on 17 November 1995. The availability of spectra from the Short Wavelength Spectrometer (SWS) on ISO is a landmark in the study of interstellar ices and organics; they provide a wealth of data in the 2-20 microns region of the spectrum covering the principal solid state resonances of condensed matter in interstellar clouds. We thus have the opportunity to study many species likely to be relevant to the inventory of CNO-bearing interstellar material present at the formation of our own and other planetary systems. This paper presents a brief overview of what has been learned from the data available so far. A comparison is made between the compositions of ices in molecular clouds, protostellar condensations and comets. Key areas of uncertainty are highlighted as a basis for future research.