17:15 〜 18:45
[PPS03-P04] 小惑星リュウグウ試料の公募研究配布とOSIRIS-REx帰還試料キュレーション準備の状況報告
キーワード：サンプルリターン、キュレーション、はやぶさ2、オシリスーレックス、リュウグウ、ベンヌ
A series of recent sample return missions from extraterrestrial bodies, such as Hayabusa and Hayabusa2, OSIRIS-REx, and Chang’E-5, give us new insights of planetary sciences [1-13]. Initial analyses and phase-2 curation analyses revealed that samples returned from C-type asteroid Ryugu are similar to CI chondrites, the most primitive, volatile-rich type of meteorites ever found [2-11]. Especially, less interlayered water in phyllosilicates of Ryugu samples compared to CI chondrites [4], which could not have been clarified if they were treated in ambient air. Thus, it is very essential for scientific values of samples returned from extraterrestrial bodies to avoid terrestrial contamination, destruction, and any modification after their returns.
The Ryugu sample gas was recovered just after its return in Quick Look Facility in Australia [14, 15]. Solid Ryugu samples were partially removed and are preserved in vacuum condition in the clean chambers (CCs) in the Extraterrestrial Sample Curation Center (ESCuC) of JAXA Sagamihara campus. And rest of them are handled, described and preserved in purified nitrogen condition of the CCs [16]. One and half year after its return, we started distributing the Ryugu samples via Announcement of Opportunities (AOs). In the 1st AO (June 2022), total mass of 229 mg of individual Ryugu grains were distributed to 40 proposals. In the 2nd AO (January 2023), total mass of 217.0 mg as individual grains and aggregates were distributed to 38 selected proposers. In the 3rd AO (July 2023), total mass of 117.7 mg of solid Ryugu samples and two types of gas bottles containing the sample container gas [14, 15] were distributed to 17 selected proposers. In the latest 4th AO (December 2023), total mass of 147.0 mg are now under distribution to 22 selected proposers.
Planning for the construction of the curation facility for OSIRIS-REx returned Bennu samples started in 2021. A new clean room was built in the ISAS curation building in the fall of 2022. The nitrogen-filled CCs for the Bennu samples were designed based on those for Ryugu samples [2, 16], and were installed in the clean room at the end of 2023. Because the JAXA fraction of Bennu sample can be regarded as its remote storage, a certain fraction of the sample will remain stored in the CCs for the future generation. Two additional chambers were also attached to the CCs for infrared spectrometers, micro-FT-IR (JASCO IRT-5200) and an infrared microscope MicrOmega, which is the same instrument used for the initial description of the Ryugu sample, for the direct comparison with the Ryugu sample [2, 3]. Along with the CCs, glove boxes for additional analyses and for the storage of the samples returned from researchers were installed in the clean room. We are going to receive Bennu samples from NASA in this summer, and planning to announce AO for the Bennu samples in the FY2024 after initial descriptions in the CCs of the ESCuC [17].
References: [1] Nakamura T. et al. (2011) Science 333:1113–1116. [2] Yada T. et al. (2022) Nat. Astron. 6, 214–220. [3] Pilorget C. et al. (2022) Nat. Astron. 6, 221–225. [4] Yokoyama T. et al. (2022) Science, 379, DOI: 10.1126/science.abn7850. [5] Nakamura T. et al. (2022) Science 379, DOI: 10.1126/science.abn8671. [6] Noguchi T. et al. (2022) Nat. Astron. 7, 170-181. [7] Okazaki R. et al. (2023) Science 379, DOI: 10.1126/science.abo0431. [8] Naraoka H. et al. (2023) Science 379, DOI: 10.1126/science.abn9033. [9] Yabuta H. et al. (2023) Science 379, DOI: 10.1126/science.abn9057. [10] Ito M. et al. (2022) Nat. Astron. 6, 1163–1171. [11] Nakamura E. et al. (2022) Proc. Jpn. Acad. Ser. B, 98, 227-282. [12] Russell S. S. et al. (2024) Lunar Planet. Sci, abstract #1197. [13] Zhou C. et al. (2022) Nat. Comm. 13, 5336. [14] Okazaki R. et al. (2022) Sci. Adv., 8, eabo7239. [15] Miura Y. N. et al. (2022) Earth Planets Space 74, 76. [16]Yada T. et al. (2023) Earth Planets Space 75, 170. [17] Fukai R. et al. (2024), this meeting.
The Ryugu sample gas was recovered just after its return in Quick Look Facility in Australia [14, 15]. Solid Ryugu samples were partially removed and are preserved in vacuum condition in the clean chambers (CCs) in the Extraterrestrial Sample Curation Center (ESCuC) of JAXA Sagamihara campus. And rest of them are handled, described and preserved in purified nitrogen condition of the CCs [16]. One and half year after its return, we started distributing the Ryugu samples via Announcement of Opportunities (AOs). In the 1st AO (June 2022), total mass of 229 mg of individual Ryugu grains were distributed to 40 proposals. In the 2nd AO (January 2023), total mass of 217.0 mg as individual grains and aggregates were distributed to 38 selected proposers. In the 3rd AO (July 2023), total mass of 117.7 mg of solid Ryugu samples and two types of gas bottles containing the sample container gas [14, 15] were distributed to 17 selected proposers. In the latest 4th AO (December 2023), total mass of 147.0 mg are now under distribution to 22 selected proposers.
Planning for the construction of the curation facility for OSIRIS-REx returned Bennu samples started in 2021. A new clean room was built in the ISAS curation building in the fall of 2022. The nitrogen-filled CCs for the Bennu samples were designed based on those for Ryugu samples [2, 16], and were installed in the clean room at the end of 2023. Because the JAXA fraction of Bennu sample can be regarded as its remote storage, a certain fraction of the sample will remain stored in the CCs for the future generation. Two additional chambers were also attached to the CCs for infrared spectrometers, micro-FT-IR (JASCO IRT-5200) and an infrared microscope MicrOmega, which is the same instrument used for the initial description of the Ryugu sample, for the direct comparison with the Ryugu sample [2, 3]. Along with the CCs, glove boxes for additional analyses and for the storage of the samples returned from researchers were installed in the clean room. We are going to receive Bennu samples from NASA in this summer, and planning to announce AO for the Bennu samples in the FY2024 after initial descriptions in the CCs of the ESCuC [17].
References: [1] Nakamura T. et al. (2011) Science 333:1113–1116. [2] Yada T. et al. (2022) Nat. Astron. 6, 214–220. [3] Pilorget C. et al. (2022) Nat. Astron. 6, 221–225. [4] Yokoyama T. et al. (2022) Science, 379, DOI: 10.1126/science.abn7850. [5] Nakamura T. et al. (2022) Science 379, DOI: 10.1126/science.abn8671. [6] Noguchi T. et al. (2022) Nat. Astron. 7, 170-181. [7] Okazaki R. et al. (2023) Science 379, DOI: 10.1126/science.abo0431. [8] Naraoka H. et al. (2023) Science 379, DOI: 10.1126/science.abn9033. [9] Yabuta H. et al. (2023) Science 379, DOI: 10.1126/science.abn9057. [10] Ito M. et al. (2022) Nat. Astron. 6, 1163–1171. [11] Nakamura E. et al. (2022) Proc. Jpn. Acad. Ser. B, 98, 227-282. [12] Russell S. S. et al. (2024) Lunar Planet. Sci, abstract #1197. [13] Zhou C. et al. (2022) Nat. Comm. 13, 5336. [14] Okazaki R. et al. (2022) Sci. Adv., 8, eabo7239. [15] Miura Y. N. et al. (2022) Earth Planets Space 74, 76. [16]Yada T. et al. (2023) Earth Planets Space 75, 170. [17] Fukai R. et al. (2024), this meeting.