Introduction Click to copy section linkSection link copied! Polycyclic aromatic hydrocarbons (PAHs) have been detected in meteorites, (1) comets, (2) on Titan, (3) and within interplanetary cosmic dust grains. (4) They are an important source of carbon (5,6) in the known universe, which has potential implications for the origin of life. (7) It has also been suggested that PAHs influence the evolution of galaxies and the formation of planets and stars.