Hayabusa2 Middle Altitude Observation Operation Results and Hovering Strategy

Abstract

Asteroid Explorer Hayabusa2 arrived at asteroid Ryugu in June of 2018. During its stay around Ryugu, Hayabusa2 will undertake several challenging missions such as collecting soil samples and deploying rovers, a lander, and an impactor. Before the spacecraft attempts these missions, our initial and most important work is to reveal the asteroid’s characteristics and properties. Science equipment is used to obtain data for use in making an asteroid model and for the landing site selection (LSS) of sample soil collection and rover/lander deployment. The LSS requires surface images taken from an altitude of around 5 km. Middle altitude observation was the operation needed to meet this requirement. This paper presents an overview of the operation, design, and study of hovering at a 5-km altitude from the surface, and specifically describes the RHC hovering method and Monte Carlo analysis of hovering trajectory and dV. It also describes the actual operation results.