The interplanetary dust particles commonly called IDPs are micrometric extraterrestrial grains (typical size of ten microns). They are collected by NASA’s stratospheric aircrafts (at an altitude of ~ 25 km). Their origin asteroidal and/or cometary has always been a subject of investigation. In recent years we have conducted a systematic analysis of IDPs using infrared micro-spectroscopy through a collaboration with the SMIS beamline at the SOLEIL synchrotron. This work reveals, in one hand, the connection between asteroids/comets and extraterrestrial material collected for laboratory studies, and gives in another hand, valuable information on the relationship between organic matter and mineral phases probably due to physical and chemical processes in the primitive nebula.
A multidisciplinary team involving researchers from the IAS, the CIMAP, the IPNO, the GANIL, and Rio de Janeiro's PUC Catholic University has characterized in the laboratory the effects of heavy cosmic rays on the structure and sputtering of water ice in interstellar and planetary environments. These experiments are used to study phase changes induced by swift heavy ions, similar to the Galactic cosmic rays. They complement and extend the knowledge already obtained at lower energies. In addition to the ice phase change, these studies reveal the importance of water ice molecules released in the gas phase by swift heavy Galactic ions, or sputtering of interstellar ices present in dense and cold interstellar clouds.
Ten aldehydes, including two sugars potentially important for prebiotic chemistry, have for the first time been identified in organic residues issued from photochemistry of interstellar ice analogues, produced in the laboratory by the IAS MICMOC/SUGARS experiment.
Living organisms use amino acids exclusively in their L enantiomeric form, a fact known as homochirality. However, the abiotic synthesis of these molecules do produce racemic mixtures (L=D) and the origin of the asymmetry remains hypothetical. The “Astrochimie et Origines” team at IAS operates an experiment dedicated to the photochemistry of ices as templates of interstellar/pre-cometary ices. These ices may be irradiated by an asymmetric light, a circularly polarized, which promotes enantioselectivity in chiral molecules. New results show that enantioselectivity obtained on five different amino acids allows confirming previous results and may help to further precise the astrophysical scenario that may be responsible for the origin of the biomolecular asymmetry at the surface of the primitive Earth.