ReACT stands for “Remote sensing of Aerosols, Clouds and Trace gases”, to describe the research focus of the respective research team led by Dr. Vassilis Amiridis. ReACT consists of highly motivated scientists within the field of Atmospheric Sciences, combining a number of Post-doc researchers, Ph.D. and M.Sc. students as well as other research and technical staff, using the resources, infrastructure and experience of the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS). IAASARS is one of the three Research Institutes of the National Observatory of Athens (NOA), which is the oldest research organization in Greece, founded in 1842. ReACT operates within the broader Remote Sensing group of the IAASARS/NOA, contributing to the BEYOND Center of Excellence for EO-based monitoring of natural disasters in south-eastern Europe.