Concept Study for Japanese Comet Sample Return Exploration in the 2030s

In 2020, the Japanese probe Hayabusa2 successfully returned samples from the asteroid Ryugu, which are currently being analyzed worldwide and have yielded numerous scientific results. Japan is also planning a sample return mission from the Martian satellite Phobos, MMX, for its launch in 2026. Further, JAXA has been studying a Next Generation Small Body Sample Return mission in the 2030s to explore more primitive bodies than Ryugu. Conceptual studies have been conducted on target bodies, science instruments, spacecraft systems, and operation methods. As a result of discussions, comets have been selected as the primary target so far. A spacecraft system that allows for flexible comet proximity operations has also been investigated, considering the lessons learned from Hayabusa2. It consists of a transport vehicle for the round-trip cruise and a 100 kg class lander for sampling during the comet proximity phase. This paper overviews our comet sample return exploration of the 2030s, including mission objectives, spacecraft systems, and operational plans.