Concerns of Organic Contamination for Sample Return Space Missions

Abstract

Analysis of organic matter has been one of the major motivations behind solar system exploration missions. It addresses questions related to the organic inventory of our solar system and its implication for the origin of life on Earth. Sample return missions aim at returning scientifically valuable samples from target celestial bodies to Earth. By analysing the samples with the use of state-of-the-art analytical techniques in laboratories here on Earth, researchers can address extremely complicated aspects of extra-terrestrial organic matter. This level of detailed sample characterisation provides the range and depth in organic analysis that are restricted in spacecraft-based exploration missions, due to the limitations of the on-board in-situ instrumentation capabilities. So far, there are four completed and in-process sample return missions with an explicit mandate to collect organic matter: Stardust and OSIRIS-REx missions of NASA, and Hayabusa and Hayabusa2 missions of JAXA. Regardless of the target body, all sample return missions dedicate to minimise terrestrial organic contamination of the returned samples, by applying various degrees or strategies of organic contamination mitigation methods. Despite the dedicated efforts in the design and execution of contamination control, it is impossible to completely eliminate sources of organic contamination. This paper aims at providing an overview of the successes and lessons learned with regards to the identification of indigenous organic matter of the returned samples vs terrestrial contamination.

Salt grains in hypervelocity impacts in the laboratory: Methods to sample plumes from the ice worlds Enceladus and Europa

“…However, as noted by among others, Chan et al. (2020), the use of aerogels as capture media may not be ideal. To give just one example, the presence of organic solvents in the aerogel manufacturing process (e.g., Sandford et al.…”

Concepts for the Future Exploration of Dwarf Planet Ceres’ Habitability

“…A mission contamination knowledge campaign will include monitoring witness materials during curation analyses to track the types of abundances of contaminants accumulated over time. Lessons can be learned from previous and ongoing sample return missions (e.g., see Chan et al 2020 The mission team should apply state-of-the-art contamination control protocols, for example, analysis in a class 100 (i.e., ISO 5) clean laboratory. However, a review of lessons learned from past sample return missions by Chan et al (2020) shows that contamination cannot be avoided.…”

Organic Matter in the Solar System—Implications for Future on-Site and Sample Return Missions

“…The existence of organic molecules in the atmosphere of the Saturnian moon Enceladus account for a favourable environment suited for the formation of life's precursors and thus possibly host information on the origin of life (e.g., Khawaja et al 2019;Postberg et al 2008Postberg et al , 2009. As sample return missions aim to deliver the most pristine, unaltered samples from another celestial object to Earth, proper contamination control is imperative so as not to compromise the pristine nature of the extra-terrestrial sample (Chan et al (2020) and Ferriere et al (2020) -this issue).…”