European spacecraft reaches asteroid impact site to study NASA collision
The European Space Agency's Hera probe has arrived at the Didymos asteroid system to investigate the aftermath of the 2022 DART mission.
The European Space Agency (ESA) Hera spacecraft has reached the Didymos asteroid system to inspect the site where NASA deliberately struck the moonlet Dimorphos in September 2022, according to a Times of India report citing the Associated Press.
The spacecraft is currently observing the binary asteroid system from a distance of approximately 25 to 30 kilometres. This early characterisation phase aims to collect broad observations of the two objects to see how Dimorphos appears following the collision.
The mission follows NASA's Double Asteroid Redirection Test (DART), which crashed a 580 kg spacecraft into Dimorphos on September 26, 2022. The impact, travelling at approximately 6.1 kilometres per second, shortened the asteroid's orbital period around Didymos by approximately 33 minutes.
Hera's objectives include measuring the mass, composition, and internal structure of the asteroid to understand how the impact changed its physical form. Scientists want to determine the momentum enhancement factor, which measures how effectively an impact transfers momentum, including the force from ejected debris.
The spacecraft is expected to move closer, to approximately 20 kilometres, in December for a more detailed investigation. The mission will also deploy two CubeSats, Juventas and Milani, to conduct closer studies of the surface and internal structure.