GOMOS ready for lift-off

An ozone monitoring probe on board the European Space Agency’s ENVISAT satellite is expected to produce as much data as 360 ground-based stations.

GOMOS (Global Ozone Monitoring by Ocultation of Stars) will use five light detection modules, designed by Sira Electro-Optics, to observe preselected stars just before they pass behind the earth.

As light from stars travels through the earth’s atmosphere, certain wavelengths are absorbed, and GOMOS will be able to calculate the amount of ozone from the resulting spectrum, thus building three-dimensional maps of the ozone layer.

ENVISAT is scheduled for launch in late 2000, and during the mission, as well as measuring seasonal changes in ozone concentrations as small as 0.1% per year, GOMOS will also measure NO2, NO3, water vapour, aerosols and vertical temperature distribution.