NASA Curation Preparation for Ryugu Sample Returned by JAXA’s Hayabusa2 Mission
Keiko Nakamura-Messenger1, Kevin Righter1, Christopher J. Snead2, Francis M. McCubbin1, Lisa F. Pace1, Ryan A. Zeigler1,& Cindy Evans1
1
NASA Johnson Space Center, Houston, TX USA, 2JETS at NASA Johnson Space Center, Houston, TX, USA
The NASA OSIRIS-REx and JAXA Hayabusa2 missions to near-Earth asteroids Bennu and Ryugu share similar
mission goals of understanding the origins of primitive, organic-rich asteroids. Under an agreement between JAXA and NASA,
there is an on-going and productive collaboration between science teams of Hayabusa2 [1] and OSIRIS-REx missions [2].
Under this agreement, a portion of each of the returned sample masses will be exchanged between the agencies and thescientific results of their study will be shared. NASA’s portion of the returned Hayabusa2 sample, consisting of 10% of thereturned mass, will be jointly separated by NASA and JAXA. The sample will be legally and physically transferred to NASA’s
dedicated Hayabusa2 curation facility at Johnson Space Center (JSC) no later than one year after the return of the Hayabusa2
sample to Earth (December 2020). The JSC Hayabusa2 curation cleanroom facility design has now been completed. In thesame manner, JAXA will receive 0.5% of the total returned OSIRIS-REx sample (minimum required sample to return 60 g,
maximum sample return capacity of 2 kg) from the rest of the specimen [2]. No later than one year after the return of theOSIRIS-REx sample to Earth (September 2023), legal, physical, and permanent custody of this sample subset will betransferred to JAXA, and the sample subset will be brought to JAXA’s Extraterrestrial Sample Curation Center (ESCuC) at
Institute of Space and Astronautical Science, Sagamihara City Japan.
Both the Hayabusa2 sample to be sent to NASA and the OSIRIS-REx sample to be sent to JAXA will be unprocessed
and representative of the returned bulk sample. “Unprocessed” means that the sample will be handled in a way that minimizes
chemical and physical changes to the sample, including avoidance of harsh radiation and heating environments such as
electron beams and Raman microscopy. The exchange samples will also be protected from organic and other forms ofcontamination to the greatest extent possible. “Representative” means that the separated sample has, as well as can be
determined on the unprocessed sample, very similar characteristics to the bulk returned sample, including grain size, color, andother physical properties readily determined by optical observation.
The overarching objectives of NASA’s Hayabusa2 curation are to preserve and protect the returned Ryugu subset
samples to maximize the science return. Curation scientists at JSC together with ESCuC members and the OSIRIS-REx
science team have been working to identify requirements on contamination and sample environmental controls. TheHayabusa2 curation requirements can be categorized into the following nine major responsibilities: 1) Contamination control,
2) Curation procedures for solid and gas samples from Ryugu surfaces, 3) Clean laboratory design and construction, 4).
Sample characterization for catalog (non-destructive organic-nonorganic lithology identification in a glovebox), 5) Sample
distribution, and 6) long term curation activity. Many of the aspects of NASA Hayabusa2 curation for the Ryugu samples are
already well developed and have strong heritage at JSC. Examples of existing knowledge and application in this area include
ppb level organic residue monitoring of the gaseous curation grade nitrogen, precision cleaning of ultrapure water circulatingin the clean labs, particle count monitoring, and metal material control for terrestrial trace element contamination control(Apollo, Genesis samples), and sample handling of small particles (cosmic dust, Stardust cometary particles, Hayabusa1
asteroid samples), to mm-cm sized rocks (Antarctic meteorites). The Hayabusa2 sample storage and handling facility at JSC
have been co-designed with the OSIRIS-REx sample curation clean facility to protect the samples from contamination, crosscontamination, temperature excursions, and moisture that could alter the sample. The construction of the facility will start in2018 [3].
As with every new extraterrestrial collection, returned primitive Ryugu samples bring special new requirements forpotentially organic rich samples. Hayabusa2 mission will attempt to collect three samples from the surface of the asteroid inorder to return a minimum of 100 mg of material. Prior to its third touchdown, Hayabusa2 will release an impactor to theasteroid that will create a small crater, possibly exposing more pristine materials from beneath the surface from which sample
collection may be attempted. Each of the three samples may have different characteristics and they should be properly handled
to preserve them. Hayabusa2 Science Team will attempt to extract the gas sample before opening the pneumatically sealed
sample container. JSC will develop the gas sample curation and handling technique under our advanced curation activity [4].
References: [1] Watanabe S. et al. (2017) Space Science Reviews, 208, 3-16. [2] Lauretta D.S. et al. (2017) Space ScienceReviews, in press. [3] Righter et al. (2017) this volume. [4] McCubbin F.M et al. (2017) this volume.