Sulphur dioxide from the Mt. Sinabung volcanic eruption in Indonesia measured by the Copernicus Sentinel-5P mission on 19 February 2018. This image is based on preliminary data that have not been fully calibrated or validated. Launched on 13 October 2017, Sentinel-5P is the first Copernicus mission dedicated to monitoring our atmosphere. The satellite carries the state-of-the-art Tropomi instrument to map a multitude of trace gases such as nitrogen dioxide, ozone, formaldehyde, sulphur dioxide, methane, carbon monoxide and aerosols – all of which affect the air we breathe and therefore our health, and our climate.