Global Ozone Monitoring by Occultation of Stars (GOMOS), is an instrument on board the European satellite Envisat launched 1 March 2002.
It is the first space instrument dedicated to the study of the atmosphere of the Earth by the technique of stellar occultation.
It is aimed to use GOMOS to build a climatology of ozone and related species in the middle atmosphere (15 to 100 km).
In addition, two high spectral resolution channels centred at 760 and 940 nm allow measurements of O2 and H2O and two fast photometers are used to correct star scintillation perturbations and to determine high vertical resolution temperature profiles.
GOMOS was first proposed in 1988 as an Announcement of Opportunity instrument dedicated to be a part of the Earth Observation Polar Platform Mission, the former name of Envisat.