Participation in the 84th International Meteorite Conference – Of course, the topic is the OSIRIS-REx return sample research!

　The 84th International Meteorite Conference was held in Brussels, Belgium, from July 29 to August 2. Presentations and discussions on the latest returned samples and meteorite research were held in the stately historic building of the Royal Belgian Academy of Sciences, the venue of the conference.

　The main topic of this year's conference was the OSIRIS-REx return sample research, which was presented for the first time at the Meteorite Conference since the return of the spacecraft’s sample capsule containing material from asteroid Bennu last September, with many research results presented during the first full day and the morning of the second day.

　Similar to asteroid Ryugu (the sample returned by JAXA’s Hayabusa2 mission), asteroid Bennu most closely resembles CI chondrite meteorites, unlike what was initially estimated from spacecraft data. However, it differs from Ryugu in that it is rich in phosphate minerals, and its organic matter is rich in nitrogen, whereas Ryugu material is rich in sulfur. These differences indicate that the primordial asteroids (from which both Ryugu and Bennu are thought to originate) that formed at the outer edges of the early Solar System were rich in variations.

　Many new perspectives on not only return sample research but also existing meteorite research were presented and actively discussed. From ASRG, Dr. Yada presented the status of preparation for receiving the OSIRIS-REx return sample, which would journey from NASA to JAXA this summer. Along with presentations regarding the curation of future sample return missions such as the Artemis mission and the Martian Moons eXploration (MMX) mission, there was a wide-ranging discussion on issues for future return sample curation (e.g. cryogenic storage, prevention of magnetic contamination, etc.).

　The summer heat in Europe has been getting severe in recent years, and on some days it became so hot in the venue without air conditioning that many people were seen waving the name tags hanging from their necks as if they were fans. However, it was much cooler than the summer in Japan (the temperature never exceeded 30°C), it was difficult to return to Japan during the heat wave, making us want to extend our stay and continue the scientific discussion!