The European Space Agency's (ESA) Hera spacecraft is en route to the Didymos binary asteroid system. Its primary target is the moonlet Dimorphos, which was intentionally struck by NASA's DART (Double Asteroid Redirection Test) spacecraft in September 2022. Hera's mission is to perform a detailed post-impact survey of the first asteroid whose orbit was measurably altered by human action.
Launched in late 2025, Hera is scheduled to arrive at the Didymos system in late 2026. The mission aims to transform the DART impact experiment into a well-understood and repeatable planetary defense technique. By closely studying the crater left by DART and measuring Dimorphos's mass and composition, scientists hope to gain critical insights into asteroid deflection strategies.
The spacecraft carries a suite of instruments, including two CubeSats named Juventas and Milani, which will perform additional close-proximity observations. The data collected will help assess the momentum transfer from the DART impact and the structural properties of the asteroid, which are key factors for future planetary defense missions.
Hera represents a cornerstone of international collaboration in planetary defense. The mission is part of the larger Asteroid Impact and Deflection Assessment (AIDA) cooperation between ESA and NASA, demonstrating a global effort to develop methods for protecting Earth from potential asteroid impacts.
