Hera is a space mission in development at the European Space Agency in its Space Safety program, its primary objective is to study the Didymos binary asteroid system that was impacted by DART and contribute to validation of the kinetic impact method to deviate a near-Earth asteroid in a colliding trajectory with Earth.

It will measure the size and the morphology of the crater created by and momentum transferred by an artificial projectile impacting an asteroid, which will allow measuring the efficiency of the deflection produced by the impact. It will also analyze the expanding debris cloud caused by the impact. The spacecraft was launched on 7 October 2024 and will also study the results of DART impactor, four years after NASA’s mission. DART impacted the asteroid Dimorphos, the smaller of two objects forming the binary asteroid 65803 Didymos, on 27 September 2022. Hera has a mass of 1128 kilograms and carries a payload of cameras, an altimeter, and a spectrometer. It will also carry two nano-satellite CubeSats, called Milani and Juventas. Hera will fully characterise the composition and physical properties of the binary asteroid system including, for the first time, the sub-surface and internal structures. It will also perform technological demonstrations linked to operations in the vicinity of a small body and the deployment and the communication with CubeSats in interplanetary space.

Thermophysical Modelling of Eclipse and Occultation Events in Binary Asteroid Systems

Planetary defence mission Hera heading for deflected asteroid

SpaceX rocket launches Europe’s Hera planetary defense probe to visit asteroid smacked by NASA