That is correct. I have an ambition to diagnose the diversity of these natural substances from the view of chemistry. At the time of the first mission of "Hayabusa," we were requested to evaluate the sample collected by the explorer. I was also approached by JAXA to develop the next project of "Hayabusa2," which might require new operations and special analysis of organic materials. In this way, my relationship with JAXA grew deeper since then (guest associate professor at JAXA in 2015-2017).

Itokawa is rocky. In short, it is low concentration of carbon. We found a slight signal of water, but the amount of carbon, which is my specialty in organic chemistry, was infinitesimally low. However, if there is a carbon signal, I was requested to find out the origins of carbon and with the detailed profile. As the amount of sample was small, the analysis was very difficult. But by confronting the (extremely) small scale of analysis, new ingenuity was born, which was utilized in the technological development of "Hayabusa2." From the Itokawa experience, standards for the amount of sample, which determines the level of elucidation, became clear.

Yes. The various experiences gained from the first "Hayabusa" mission were very good lessons. Thanks to the experiences, when we recovered the re-entry capsule this time and opened it in the clean room to take out the sample-container, we knew the most critical point to focus on. The zone defense of each special field by the sampler team composed of science and engineering specialists was perfect.
First, after taking out the sample-container, we connected it to a special analysis line set up in the clean room. We then simultaneously collected and analyzed the gas in the container. In Japan and Australia, we conducted thorough rehearsals many times, despite the difficulties in adjusting the schedule under the COVID-19 calamity. Nevertheless, when the time came for the real game to begin, I felt that everyone was growing excited (in a good way, of course, under good tension). It was a series of breathtaking moments. The whole team purposefully talked to each other, took deep breaths, encouraged each other, and all members enjoyed the joy of having witnessed the moment of success. It was a truly precious moment for me as a scientist.

JAMSTEC has its headquarters in Yokosuka and institutes in Yokohama and Kochi. The "Hayabusa2" analysis team will proceed with analysis at the Yokosuka Headquarters and the Kochi Institute. At the Yokosuka Headquarters, an international team composed of Japan, the U.S., and Europe, together with Kyushu University, NASA, and others, will analyze the abundance, isotopic composition, and inorganic ion composition of carbon and nitrogen in Ryugu, as well as analyze what kind of organic molecules carbon and nitrogen make at the molecular level.
At the Kochi institute (Deputy Group Leader Senior Researcher Dr. Motoo Ito), they mainly use a secondary ion mass spectrometer, an ultra-high performance machine, to analyze what kind of mineral structure the sample has. And if the sample contains carbon or nitrogen, we will visualize its spatial distribution. Unlike Itokawa, Ryugu is thought to have both water and carbon. If so, there is a possibility that the organic matter produced by the reaction of these substances could be there. It's exciting just to think about it.

Thank you for asking me such an inspiring question. I believe that an analysis of the time of the birth of life, "midnight" in other words, will take place on a different occasion, not the analysis of the sample brought back by "Hayabusa2."(😉) However, it is true that there is no other place where you can see the environment before an ocean and the Earth were formed. Ryugu is the only place where we can see by ourselves what the Solar System looked like before the formation of planets. Then, there are carbon and water, and when they accumulate, they eventually become an ocean. As JAMSTEC researcher Dr. Yoshimura presented last year at the Lunar and Planetary Science Conference (LPSC), we may be able to see the first inorganic chemistry as water reacts with the minerals from Ryugu. I would like to learn more about the interaction between organic and inorganic matter before the formation of an ocean and the earth.

What is also noteworthy about the operations conducted by "Hayabusa2" at Ryugu is the collection of samples not only from the surface, but also from the subsurface. The surface of Ryugu is expected to have a history of exposure to sunlight. However, the subsurface samples are less affected by sunlight. In short, there is a possibility that we can get information on a younger Ryugu.
In addition, NASA's Osiris-REx spacecraft will travel to asteroid Bennu to bring back samples. We have a hope for the comparative analysis of Ryugu's and Bennu's samples. We can find out whether the evolution of materials seen in Ryugu is a unique phenomenon or a universal phenomenon in asteroids. If there is a difference, it suggests that asteroids have different histories. By comparing both samples, we may be able to observe the diversity of interactions between water, organic matter, and minerals. The comparison of the analysis of samples from Ryugu and Bennu through the bidirectional cooperation between Japan and the U.S. is, therefore, scientifically significant. The 2020s is going to be a decade to keep an eye on.

That is correct. When I joined the Organic Geochemistry and Cosmochemistry laboratory at the University of Tsukuba (Professor Emeritus Kaoru Harada and Professor Emeritus Akira Shimoyama), I've learned various "manners" of organic analysis. For example, I learned how to prevent "contamination" and how to extract information on a sample in the best possible way. This also included many protocols based on the know-how that was created in the 1960s during the process of the Apollo lunar program and the Viking Mars program. Of course, there are a number of new developments by our own generation, but they were created based on the grand design and golden rules created and polished up by pioneers. On top of that, there is what we can call "data," and on top of that, there is what we can call champion data such as the Ryugu analysis. It is impressive, because this is the succession of technology on a 50-year scale.
I myself am very fortunate to be able to conduct the first analysis in human history and describe asteroid "Ryugu" while I am still an active scientist. I am going to approach my analysis with respect for my predecessors.