SAGE III on ISS

NASA’s SAGE III instrument on the International Space Station observes stratospheric ozone, aerosols and water vapor using solar and lunar occultation. Launched on February 19, 2017 and installed externally on the station, it measures light passing through the atmospheric limb at sunrise and sunset to retrieve vertical profiles of gases and particles. Its sampling extends approximately from 70°N to 70°S. The record supports studies of ozone recovery, volcanic aerosols, wildfire impacts and stratospheric composition; occultation events provide geographically distributed profiles rather than continuous daily maps at every location.