ESA’s Earth Explorer Aeolus satellite lifted off on a Vega rocket from Europe’s Spaceport in Kourou, French Guiana, at 21:20 GMT (23:20 CEST, 18:20 local time) on 22 August 2018. Aeolus carries one of the most sophisticated instruments ever to be put into orbit. The first of its kind, the Aladin instrument includes revolutionary laser technology to generate pulses of ultraviolet light that are beamed down into the atmosphere to profile the world’s winds – a completely new approach to measuring the wind from space. By profiling the lowermost 30 km of the atmosphere, Aeolus will give scientists global information on the speed of the wind in near-real time. This will improve our understanding of how wind, pressure, temperature and humidity are interlinked. This new mission will also provide insight into how the wind influences the exchange of heat and moisture between Earth’s surface and the atmosphere. These aspects are important for understanding climate change. As well as advancing science and improving weather forecasts, data from Aeolus will be used in air-quality models to improve forecasts of dust and other airborne particles that affect public health.