When satellites eventually fall back down to Earth, they mostly burn up because of the friction caused by the atmosphere. Scientific data about this atmospheric reentry process is urgently needed to design future satellites for a quick, safe and sustainable demise at the end of their mission – reducing risks on the ground and in space.

The European Space Agency (ESA) successfully manoeuvred its remaining two Cluster satellites to ensure they can both be observed from a plane as they reenter the atmosphere on 31 August and 1 September 2026.

Space activities are unlike any others. They interact not just with Earth, but with three interconnected environments: Earth, Earth’s orbit, and the Moon and deep space. On Earth, we aim to reduce the space sector’s environmental impacts while maximising the societal and environmental benefits of our missions. In orbit, we manage space debris and collision risks to maintain safe and secure operations. For the Moon and deep space, we are laying the foundations to minimise the impact of our missions on and around other celestial bodies.

Guided by our core values, ESA is committed to making its activities