Abstract

Astrochemistry is the study of molecules outside the atmosphere of the Earth. Between stars, there is highly diluted material composed of gas-phase molecules and small dust particles. It is what we call the interstellar medium. In the process of forming stars and planets, this material undergoes many different physical conditions with densities between 10 and 10^12 particles per cm2 and temperatures between 5 and 10000K. The chemistry taking place in the interstellar medium depends then on the type of object that we are studying. In quiescent dense clouds (moderate densities, low temperature and no UV photons) for instance, chemistry at the surface of dust particles plays a major role whereas at the surface of protoplanetary disks (where planets form) the UV radiation form the star dominates the chemistry.

In this presentation, I will make a brief introduction to the type of chemistry that we find in the interstellar medium and will show some few examples of astrochemical problems.