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SAMPLE CURATION AT A LUNAR OUTPOST. C. C. Allen 1, G. E. Lofgren1, A. H. Treiman2, and M. L. Lindstrom3 1NASA , Houston, TX 77058 USA carlton.c.allen@.gov [email protected] 2Lunar and Planetary Institute, Houston, TX 77058 USA [email protected] 3NASA Headquarters, Washing- ton, DC 20546 USA [email protected]

Introduction: The six Apollo surface missions re- particularly iron-rich pyroclastic glass and ilmenite- turned 2,196 individual rock and soil samples, with a bearing material. Ice-rich deposits have been pre- total mass of 381.6 kg [1]. Samples were collected dicted in permanently-shadowed locations, and the based on visual examination by the and con- verification of such deposits is an import goal for lunar sultation with geologists in the science “back room” in exploration. Other volatiles, derived from volcanic Houston. The samples were photographed during col- emissions or implanted by the solar wind, may also lection, packaged in uniquely-identified containers, prove valuable resources. and transported to the Lunar Module. All samples Lunar Outpost Curation Studies: Concepts for collected on the were returned to Earth. the collection of samples at lunar outposts were stud- NASA’s upcoming return to the Moon will be dif- ied intensively in the years following Apollo. The ferent. Astronauts will have extended stays at an out- 1988 “Geoscience at a Lunar Base” workshop [2] care- post and will collect more samples than they will re- fully considered the curation and analysis of samples turn. They will need curation and analysis facilities on on the Moon’s surface. The workshop participants the Moon in order to carefully select samples for return envisioned a complete curatorial facility at a lunar to Earth. base, similar in concept to the facility at JSC, but on a Apollo Sample Curation: The Apollo samples smaller scale. Sample handling and analysis would be are curated at the NASA Johnson Space Center (JSC) done outside the habitat, in a dust-controlled structure, in Houston, TX. To minimize contamination, the using robotic and telerobotic operation as much as samples are stored in dry, high-purity nitrogen glove- possible. boxes within class 1,000 cleanrooms. Only a limited The 1989 Lunar Science Strategy Workshop [3] set of materials is allowed to contact the samples. The represented the input of the science community to lunar samples are distributed worldwide to support NASA’s 90-Day Study. The workshop report recom- peer-reviewed research, as well as education and pub- mended that a lunar outpost should have a sample cu- lic outreach. ration facility, at ambient lunar surface conditions, Curation of lunar samples can be divided into dis- robotically operated and complemented by a prelimi- tinct, but interconnected, functions: nary examination laboratory. The most detailed scheme for handling and cura- ƒ Documentation and tracking tion of geoglic samples on the Moon is included in the ƒ Handling and subdivision “First Lunar Outpost Mission” (FLO) study conducted ƒ Preliminary examination at JSC. Treiman [4] compiled specific recommenda- ƒ Contamination and environmental control tions for sample documentation and tracking, handling ƒ Secure storage and subdivision, preliminary examination, contamina- ƒ Allocation tion and environmental control, and continued storage on the Moon. The samples returned by the Apollo astronauts are the most intensively-analyzed rocks and soils in his- Lunar Outpost (2007): The current draft of tory. Sample analysis in the decades following Apollo NASA’s Lunar Architecture [5, 6] envisions the pro- established the current understanding of lunar geology gressive build-up of a crewed outpost, commencing and clearly demonstrated where continuing research in with the first human mission. Crews on early mis- needed. New generations of scientists, new classes of sions will occupy the outpost for days or weeks, and analytical instruments, and new insights have resulted the long-term goal is continual occupation supported in continuing demand for theses samples, even 35+ by crew rotations every several months. years after their return. The outpost will likely be located at or near one of Samples also provide the raw material for future the lunar poles. The discovery and analysis of vola- utilization of . Oxygen, for life support tiles in permanently-shadowed polar craters is one of and propulsion, is a resource of high interest. Oxygen the high-priority science goals of this architecture. can be derived from oxide minerals in the lunar soil, Sample Curation at a Lunar Polar Outpost: contaminating events and environments must be Sample return to Earth is an essential part of the cur- documented. rent Architecture. However, mission restrictions on mass and volume will undoubtedly constrain the num- ƒ Storage must ensure that the samples receive mini- ber of returned samples to considerably less than the mal contamination and alteration. This implies number of samples collected. The samples transported storage remote from the habitat, other human op- to Earth will need to be carefully selected to address erations, landing areas, and flight paths. specific, high-priority research questions. Other sam- ples may be studied on the Moon, particularly if the ƒ Adequate safeguards must be used to prevent hu- aspects to be studied would be compromised by expo- man health hazards and equipment damage from sure to the spacecraft or the terrestrial environment. lunar dust. The design of the spacecraft that will return crews and samples from the lunar outpost to Earth has not ƒ The following practices for handling and curation been finalized. However, preliminary planning in- of rocks, rake samples, and soil samples are rec- cludes a mass allocation of 200 kg for samples, includ- ommended: ing packaging. This compares to the total 110.5 kg of rock and soil (without packaging) returned by Apollo o Upon collection a geological sample should 17 following three traverses. be split into subsamples for preliminary ex- Clearly the Apollo-era practice of transporting all col- amination at the lunar outpost, detailed analy- lected samples to Earth will have to be modified, and a ses on Earth, and minimally contaminated method of hi-grading samples at the lunar outpost will storage on the Moon. be required. o Storage at the lunar outpost should ensure that Sample contamination at a lunar outpost is poten- samples receive minimal contamination, and tially a much larger problem than it was during the be readily retrievable. Apollo missions. The amount of infrastructure and o Preliminary examination of the designated off-gassing associated with the outpost, as well as the sub-samples may take place in a geosciences repeated landing and liftoff of rockets, can seriously laboratory space in the outpost. contaminate unprotected samples. o Samples expected to contain volatiles should The potential health hazard posed by lunar dust, as be maintained at subfreezing temperatures un- well as the hazard to equipment posed by this highly til they are either analyzed at the outpost or abrasive material, will significantly affect outpost de- transported at subfreezing temperatures to sign and operation. These concerns present a strong Earth. argument for conducting curation activities outside of o The decision to transport a sample to Earth the habitable volume of the outpost. should be based in large part on preliminary The basic recommendations of the previous studies examination. remain valid for the curation of rock and soil samples o Samples collected but not selected for trans- collected at most locations on the Moon. However, as port to Earth should be curated on the Moon, Treiman [4] noted, these schemes are “inadequate for under conditions of minimal contamination or curation and handling of volatile-rich materials, such alteration. as might be found at the lunar poles.” In order to ef- fectively study polar volatiles, the samples must be References: [1] Heiken G. H. et al. (1991) Lunar maintained cold until they are analyzed. This will re- Sourcebook, Cambridge University Press. [2] Taylor G. J. quire either the ability to extract the volatiles on the and Spudis P. D. (1990) Geoscience at a Lunar Base, Con- Moon or the ability to transport the samples in a frozen ference Publication 3070, NASA, Washington, DC. [3] condition to Earth. Duke M. B. (1989) Lunar Science Strategy Workshop, Cura- Based on these considerations, specific to the lunar tor’s Data Center, Johnson Space Center, Houston, TX. [4] polar outpost baselined in the current Architecture, the Treiman A. H. (1993) Curation of Geological Materials at a recommendations of the previous studies are modified: Lunar Outpost, Report JSC-26194, Johnson Space Center, Houston, TX. [5] NASA (2005) Exploration Systems Archi- ƒ All geological samples must be completely docu- tecture Study, NASA-TM-2005-214062, NASA, Washing- mented and tracked. ton, DC. [6] NASA (2006) NASA Unveils Global Explora- tion Strategy and Lunar Architecture, ƒ Contamination of geological samples must be lim- http://www.nasa.gov/home/hqnews/2006/dec/HQ_06361_ES ited according to potential uses, and all potential MD_Lunar_Architecture.html