Asteroid Ryugu Before the Hayabusa2 Encounter

TL;DR

This paper reviews current knowledge of asteroid Ryugu's physical and dynamical properties based on remote sensing and modeling, aiding mission planning and scientific understanding of small Solar System bodies.

Contribution

It provides a comprehensive model of Ryugu's properties to support mission operations and scientific analysis, integrating remote sensing data and theoretical modeling.

Findings

Ryugu is a C-type near-Earth asteroid less than 1 km in diameter.

A detailed physical and dynamical model of Ryugu is constructed.

The model informs mission planning and scientific interpretation for Hayabusa2.

Abstract

Asteroid (162173) Ryugu is the target object of Hayabusa2, an asteroid exploration and sample return mission led by Japan Aerospace Exploration Agency (JAXA). Ground-based observations indicate that Ryugu is a C-type near-Earth asteroid with a diameter of less than 1 km, but the knowledge of its detailed properties is still very limited. This paper summarizes our best understanding of the physical and dynamical properties of Ryugu based on remote sensing and theoretical modeling. This information is used to construct a design reference model of the asteroid that is used for formulation of mission operations plans in advance of asteroid arrival. Particular attention is given to the surface properties of Ryugu that are relevant to sample acquisition. This reference model helps readers to appropriately interpret the data that will be directly obtained by Hayabusa2 and promotes scientific studies not only for Ryugu itself and other small bodies but also for the Solar System evolution that small bodies shed light on.