Cluster’s encore for reentry science a success

The Cluster mission formally ended in 2024, but ESA turned its final phase into a reentry data collection campaign. After four 'targeted' reentries, ESA has demonstrated a safe and controlled method for end-of-life disposal. Each reentry was repeatedly observed by a plane full of scientists, creating a unique reentry data set to study the destructive process and guide the design of safer, more sustainable satellites.

The fourth and final satellite, Tango, reentered on 1 September 2026 at 23:30:31 CEST. Earlier, on 31 August, a third satellite, Samba (Cluster II FM-7), also underwent a targeted reentry and was successfully observed by the ROSIE airborne mission 2026. The ROSIE team acquired imagery with a Nikon Z8 camera operated by the University of Stuttgart (HEFDiG). Overall, the airborne observation team captured both the Samba and Tango reentries using 29 of the 30 instruments onboard, building on lessons learned from each previous experiment to refine instrumentation and reentry prediction accuracy.

Shortly before Tango's reentry, mission team members sent a final command as a personal goodbye. About 15 minutes before reentry, Tango's signal via the Kourou ground station was lost after continuously returning telemetry until the very end. This marked the close of 26 years of operations, during which Cluster greatly improved our understanding of Earth's magnetosphere. Philippe Escoubet, Cluster Mission Manager at ESA, reflected that building the mission gave it a soul and that while its final act has passed, the Cluster family's spirit will endure.

Next, ESA's reentry specialists aim to witness a reentry from the inside with the Draco mission, scheduled for launch in 2027. Draco will carry more than 200 sensors, four cameras, and an indestructible capsule to preserve the recorded data, offering a unique perspective on what happens during fiery reentry.