The European Space Agency’s Hera spacecraft is due to reach the Didymos asteroid system in November. Its mission is to examine Dimorphos up close and gather data on the effects of NASA’s 2022 impact test, while investigating wider questions about asteroids.
Dimorphos, which measures 151 metres across, orbits the 780-metre asteroid Didymos. It became the first object in the Solar System known to have had its orbit altered by human action when NASA’s DART spacecraft struck it on 26 September 2022.
Telescopes on Earth detected a brightening after the collision, but the impact’s physical effects on Dimorphos remain unclear. Hera will survey the crash site to help scientists better understand how a kinetic impact can change an asteroid’s motion—and how the method might be used for planetary defence.
The mission is also expected to provide scientific insights beyond the impact itself. Previous spacecraft encounters have shown that asteroids can be dynamic environments with complex histories. Hera’s close-up observations will help explore 10 outstanding asteroid mysteries.
Sources: ESA Space News.