ESA Hera mission performs first major braking maneuver for asteroid rendezvous

The European Space Agency (ESA) mission Hera is preparing to rendezvous with the binary asteroid pair Didymos and Dimorphos. To achieve this, the spacecraft recently completed its first major braking maneuver on October 15. This 93-minute operation used three thrusters to reduce the probe's velocity relative to the asteroids, which is traveling at more than 12 kilometers per second relative to Earth.

ESA described this as the most difficult activity the mission has undertaken since its launch from Cape Canaveral on October 7, 2024. A second braking maneuver is scheduled for October 22 to provide the majority of the remaining deceleration, followed by three smaller adjustment maneuvers to bring the relative speed to nearly zero.

The Hera mission serves as a follow-up to NASA’s 2022 Double Asteroid Redirection Test (DART), which impacted Dimorphos to test planetary defense capabilities. Hera will provide detailed imaging and data regarding the results of that impact and the composition of the asteroid system, which is characterized as a silicon-rich rubble pile.