There is always a sunrise and sunset happening somewhere on our planet. Soon a new Belgium-led CubeSat – flying aboard Europe’s Vega launcher this Sunday – will be keeping watch. The miniature PICASSO mission will use the filtering of sunlight by Earth’s atmosphere to check the health of our protective ozone layer.

CubeSats are miniature satellites built up from standardised 10-cm boxes. The PICo-satellite for Atmospheric and Space Science Observations, or PICASSO, developed with ESA by the Belgian Institute for Space Aeronomy (BISA), is a ‘3-unit’ CubeSat with two scientific payloads. It hosts a cut-down spectrometer for monitoring the atmosphere, as well as sampling probes (called ‘SLP’) to measure space plasma around the nanosatellite.