Hera reveals Didymos and Dimorphos: first images after the Dart impact

The European Space Agency's (ESA) Hera mission has captured the first image in which the two asteroids Didymos and Dimorphos appear distinct. The photograph, taken on October 18 from a distance of 1280 kilometers, shows Dimorphos as a single bright pixel finally separated from its main body, Didymos.

The image is the result of a series of braking maneuvers initiated in early October, which slowed the probe to a relative speed of about 20 meters per second relative to the asteroid pair. On November 25, ESA will release the first detailed images of Dimorphos, the first object in the Solar System whose orbit has been altered by human action.

The Hera mission is Europe's response to an unprecedented planetary defense experiment. On September 26, 2022, NASA's Dart probe intentionally struck the asteroid Dimorphos at a speed of 6.1 km/s. The goal was to test our ability to deflect a potentially hazardous asteroid. The impact created a massive plume of debris and slowed Dimorphos's orbit around Didymos by about 33 minutes.

Hera, launched years later, has the task of closely analyzing the consequences of that historic impact. Its mission is to study the crater formed by Dart, measure the changes in Dimorphos's mass, structure, and orbit, and evaluate the effectiveness of the kinetic impactor technique for planetary defense. The two small cubesats accompanying Hera will conduct close-up observations and even attempt a landing on the altered celestial body.