Radio science experiments with the Hera mission

This thesis describes, designs, and develops the Hera Radio Science Experiment at the Didymos binary asteroid system. Hera represents the European Space Agency’s inaugural planetary defence space mission, and plays a pivotal role in the Asteroid Impact and Deflection Assessment international collaboration with the NASA DART mission that performed the first asteroid deflection experiment using the kinetic impactor technique. With the primary objective of conducting a detailed post-impact survey of the Didymos binary system following the DART impact on its small moon called Dimorphos, Hera aims to comprehensively assess and characterize the feasibility of the kinetic impactor technique in asteroid deflection while conducting in-depth investigation of the asteroid binary, including its physical and compositional properties as well as the effect of the impact on the surface and/or shape of Dimorphos. In this context, the Hera radio science experiment will allow to precisely estimate key physical parameters that are required to determine the momentum enhancement resulting from the DART impact, namely the mass, mass distribution, rotational states, relative orbits, and dynamics of the asteroids Didymos and Dimorphos. Through multi-arc covariance analysis the achievable accuracy for these parameters are presented.