IMARS Phase 2A Draft Mission Architecture and Science Management Plan for the Return of Samples from Mars Phase 2 Report of the International Mars Architecture for the Return of Samples (iMARS) Working Group.

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AstrobiologyVol. 18, No. S1 ArticleOpen AccessiMARS Phase 2A Draft Mission Architecture and Science Management Plan for the Return of Samples from MarsPhase 2 Report of the International Mars Architecture for the Return of Samples (iMARS) Working GroupTimothy Haltigin, Christian Lange, Raffaele Mugnuolo, Caroline Smith, iMARS Working Group (2016), T Haltigin, C Lange, R Mugnolo, C Smith(co-chairs), H Amundsen, P Bousquet, C Conley, A Debus, J Dias, P Falkner, V Gass, A-M Harri, E Hauber, AB Ivanov, AO Ivanov, G Kminek, O Korablev, D Koschny, J Larranaga, B Marty, S McLennan, M Meyer, E Nilsen, P Orleanski, R Orosei, D Rebuffat, F Safa, N Schmitz, S Siljeström, N Thomas, J Vago, A-C Vandaele, T Voirin, and C WhetselTimothy HaltiginSearch for more papers by this author, Christian LangeSearch for more papers by this author, Raffaele MugnuoloSearch for more papers by this author, Caroline SmithSearch for more papers by this author, iMARS Working Group (2016) T Haltigin, C Lange, R Mugnolo, and C Smith(co-chairs), H Amundsen, P Bousquet, C Conley, A Debus, J Dias, P Falkner, V Gass, A-M Harri, E Hauber, AB Ivanov, AO Ivanov, G Kminek, O Korablev, D Koschny, J Larranaga, B Marty, S McLennan, M Meyer, E Nilsen, P Orleanski, R Orosei, D Rebuffat, F Safa, N Schmitz, S Siljeström, N Thomas, J Vago, A-C Vandaele, T Voirin, C Whetsel. Published Online:1 Apr 2018https://doi.org/10.1089/ast.2018.29027.marsAboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail ContributorsSteering CommitteeDe Groot, Rolf (ESA), memberLavery, Dave (NASA), chairMay, Lisa (NASA), chairZelenyi, Lev (Russia), memberEngineering TeamBousquet, Pierre ( CNES), memberDebus, Andre (CNES), memberDias, Jorge (Portugal), memberFalkner, Peter (ESA), memberGass, Volker (Switzerland), memberIvanov, Anton (Switzerland), memberIvanov, Alexey (Russia), memberLange, Christian (CSA), co-chairLarranaga, Jonan (ESA), advisorMugnuolo, Raffaele (ASI), co-chairNilsen, Erik (NASA), memberOrleański, Piotr (Poland), memberRebuffat, Denis (ESA), memberSafa, Frederic (ESA), advisorSchmitz, Nicole (Germany), memberVoirin, Thomas (ESA), memberWhetsel, Charles (NASA), memberScience / Earth Operations TeamAmundsen, Hans (Norway), memberConley, Catherine (USA), advisorHaltigin, Tim (CSA), co-chairHarri, Ari-Matti (Finland), memberHauber, Ernst (Germany), memberKminek, Gerhard (ESA), advisorKorablev, Oleg (Russia), memberKoschny, Detlef (ESA), memberMarty, Bernard (France), memberMcLennan, Scott (USA), memberMeyer, Michael (NASA), advisorOrosei, Roberto (Italy), memberSmith, Caroline (UK), co-chairSiljeström, Sandra (Sweden), memberThomas, Nicolas (Switzerland), memberVago, Jorge (ESA), memberVandaele, Ann Carine (Belgium), memberIMAGEThe two linear depressions in this image form part of the Elysium Fossae complex, a group of troughs located in the Elysium quadrangle of Mars. These troughs are tectonic features, likely formed by the stretching, tearing and subsequent collapse of the crust resulting from the rise of the nearby Elysium volcanic province.Image credit: NASA/JPL-Caltech/MSSSPreliminary Planning for an International Mars Sample Return MissionContentsExecutive SummaryI. IntroductionII. MSR Status and AssumptionsIII. MSR Campaign Structure and ImplementationsIV. Sample Science Management PlanV. Conclusions and RecommendationsA. AppendicesExecutive SummaryABOVE IMAGEAn East Watershed for Jezero Crater. Jezero Crater is candidate future landing site that contains sediments deposited by at least three ancient rivers.This image was targeted to the eastern headlands of the river flowing in from that direction.Image credit: NASA/JPL-Caltech/Univ. of ArizonaThe International Mars Exploration Working Group (IMEWG) was formed in 1993 to provide a forum for the international coordination of Mars exploration. In 2007, IMEWG chartered the international Mars Architecture for the Return of Samples Working Group (iMARS WG), which produced a Phase 1 report in 2008 (iMARS, 2008). In 2014, IMEWG chartered an iMARS Phase 2 Working Group, comprising two panels of experts: (i) Engineering and (ii) Science/Earth Operations. The iMARS Phase 2 WG was tasked to provide: A status report on planning for a Mars Sample Return (MSR) campaign, building on missions and international developments achieved since the iMARS Phase 1 WG issued its report; andRecommendations for progressing toward campaign implementation, including a proposed sample management plan.This report presents the iMARS Phase 2 WG’s findings. It details top-level campaign requirements that would meet stated science objectives and planetary protection constraints. It presents an updated reference MSR architecture, made of three flight elements and one ground element (termed the 3+1 architecture). It provides technical and programmatic justifications for this architecture and report also discusses alternatives to the reference architecture. The WG also reports on the status of MSR technology developments conducted by several space agencies around the world, evidence of the willingness of major space stakeholders to invest in MSR implementation. This report elaborates on programmatic considerations relating to MSR, including campaign robustness, international coordination and decision-making, a provisional implementation timeline, and a possible cost-sharing model.In this report, the WG presents: A returned-sample management plan, including an organizational structure for an international Mars sample science institute that outlines roles and responsibilities of key members and describes sample return facility requirements;A science implementation plan, covering preliminary sample examination flow, sample allocation process, and data policies; andA Mars sample curation plan, including sample tracking and routing procedures, sample sterilization considerations, and long-term archiving recommendations.The WG’s key conclusions are that: It is feasible to return scientifically selected samples from Mars in 2031/33 under the proposed mission architecture, technology development roadmap, and sample management plan. A successful campaign will depend on early and binding agreements for long-term commitments by participating organisations.Returning samples from Mars will require a multidisciplinary approach. Scientific, safety and curatorial aspects of the campaign must each be considered and integrated when developing mission architecture and sample management structure.While the Mars exploration community has made progress in understanding planetary protection implications of MSR and associated technology developments, important requirements and protocols remain to be further developed.The WG’s key recommendations are that: To advance development of MSR architecture, interested international partners must declare their interests, define a cooperation framework, and determine their contributions.An internationally-tasked and -accepted planetary protection protocol for MSR should be produced as soon as possible, as this protocol will have technical and programmatic implications for the mission architecture.MSR campaign partners should establish an international MSR Science Institute as part of the campaign’s governance structure upon approval to return samples from Mars.Two key MSR enabling technologies, the Mars ascent vehicle and sample containment (“break-the-chain-of-contact”), require further investments to proceed with development.1. IntroductionABOVE IMAGENorth Polar Gypsum Dunes in Olympia Undae. These sand dunes are a type of aeolian bedform and partly encircle the Martian North Pole in a region called Olympia Undae.Image credit: NASA/JPL-Caltech/Univ. of Arizona1.1 MotivationMars Sample Return (MSR) is key to answering some of the most fundamental questions in planetary exploration: Does life exist beyond Earth? How did the Solar System evolve? The space community has long identified MSR as a main objective of planetary exploration (iMARS Phase 1, 2008; Committee on Planetary Science Decadal Survey 2010; McLennan et al., 2012). Now international partners are at the threshold of possessing the necessary knowledge and capability to return atmospheric and surface samples from Mars to Earth.While robotic orbiter and lander missions to Mars have demonstrated powerful remote-sensing and in-situ analytic capabilities, much more powerful and sophisticated analysis of martian samples will be possible in terrestrial laboratories. An MSR campaign will require the development of new technologies that future Solar System exploration missions can employ and help to prepare for crewed missions to the Red Planet.The complexity and cost involved in executing an MSR campaign is too challenging for any single nation to take on alone. A collaborative international effort will be necessary. The goal of this document, developed by representatives from iMARS Phase 2 participating organisations, is to build upon previous work by presenting a feasible approach for a potential MSR campaign that would be internationally organized, funded, and conducted.1.2 Objectives and ScopeThe international Mars Architecture for the Return of Samples (iMARS) Working Group was chartered by the International Mars Exploration Working Group (IMEWG) in 2006 to develop a potential plan for an internationally sponsored and executed Mars sample return (MSR) mission. Its purpose to outline the scientific and engineering requirements of such an international mission in the 2018–2023 timeframe.The overarching goal of the iMARS Working Group is to: “Identify how international cooperation might enable sample return from Mars, document the existing state-of-knowledge on return of samples from Mars, develop international mission architecture options, identify technology development milestones to accomplish a multi-national mission, and determine potential collaboration opportunities within the architecture and technology options and requirements, and current Mars sample return mission schedule estimates of interested nations. The activity will also identify specific national interests and opportunities for cooperation in the planning, design, and implementation of mission-elements that contribute to sample return. The Working Group’s final product(s) is expected to be a potential plan for an internationally sponsored and executed Mars sample return mission.” (iMARS WG, 2008, Appendix 1).The iMARS WG released its Phase 1 report in 2008. IMEWG chartered the iMARS Phase 2 Working Group in March 2014 to document major developments since 2008. This iMARS WG Phase 2 report provides an update of the Phase 1 report.Section 2 of this report provides baselines and assumptions for an MSR campaign, including overarching science objectives and top-level campaign requirements. This section also discusses planetary protection considerations, highlighting the need for an internationally accepted protocol for preventing forward and backward contamination of returned samples.Section 3 provides an update of MSR campaign reference architecture, describing campaign elements and considering alternative architectures. It also elaborates on key technologies required for each element and highlights critical programmatic and policy issues that must be considered for such a large international endeavour.Section 4 outlines a sample science management plan, including a sample management structure, implementation approach and curation plan intended to maximise science return. An overriding principle underlying this plan is open science: MSR science will be openly competed, and every effort will be made to involve the public.Section 5 provides conclusions and recommendations.IMAGECuriosity Self-Portrait at ‘Windjana’ Drilling Site. NASA’s Curiosity Mars rover used the camera at the end of its arm in April and May 2014 to take dozens of component images combined into this self-portrait where the rover drilled into a sandstone target called “Windjana.”Image credit: NASA/JPL-Caltech/MSSSII. MSR Status and AssumptionsABOVE IMAGENASA to Launch Mars Rover in 2020 (Artist’s Concept). NASA’s Mars 2020 Project will re-use the basic engineering of NASA’s Mars Science Laboratory/Curiosity to send a different rover to Mars, with new objectives and instruments. This artist’s concept depicts the top of the 2020 rover’s mast.Image credit: NASA/JPL-CaltechThis section starts with a summary of MSR reference mission architecture described in the 2008 iMARS WG Phase 1 report and then provides a high-level summary of advances made since 2008. The iMARS WG was not tasked in Phase 2 with developing science drivers or objectives for an MSR campaign. Thus, science objectives outlined by the MSR End-to-End International Science Analysis Group (McLenan et al., 2011) are used as a baseline.2.1 Summary of iMARS Phase 1 Reference ArchitectureThe reference mission architecture described in the iMARS WG Phase 1 report proposed two flight elements, a Lander Composite and an Orbiter Composite. Launched separately to Mars, they would work together to return at least one Mars sample container to Earth. This architecture included significant ground elements: operations centres, at least one sample receiving facility, and at least one curation facility.In the Phase 1 concept (Figure 2-1), the Lander Composite – including a surface rover and a Mars Ascent Vehicle (MAV) – would perform a direct entry and a soft landing on the surface of Mars. The rover would drive away from the Lander platform to acquire surface samples, including rock cores, and then return to the Lander platform. The platform would be equipped with mechanisms to load samples into a container on the MAV. The platform also would have the capability to acquire samples in case of rover failure. All equipment in contact with Mars samples would have to be sterile in order to avoid false positive results when analysed on Earth. The MAV would launch the sample container into low-Mars orbit for retrieval by the Orbiter Composite.FIGURE 2-1: iMARS WG Phase 1 reference architecture.The Orbiter Composite would include propulsion, a rendezvous and capture system, and an Earth Return Vehicle (ERV). At Earth, the ERV would release an Earth Entry Vehicle (EEV)—much like those employed on the NASA Stardust and Genesis sample return missions. Once the EEV landed, the ERV would then divert away from Earth on a non-return trajectory.The ground segment for this architecture would consist of mission and control centres for both flight composites, a set of telecommunication ground stations, and sample return and curation facilities. Sample return facilities (SRFs) would provide containment for flight hardware and samples returned from Mars to meet planetary protection requirements. The SRF’s primary function would be to protect the Earth from back contamination while necessary test protocols were conducted to determine if the samples were safe for release.Challenges posed by this architecture included:Mass incompatibility of the first element with available launch capabilities,Programmatic weakness in schedule management and failure mitigation plans, andHigh cost of the first element.These issues have been addressed in the updated architecture presented in this report.2.2 Advances Since 2008Since 2008, numerous exploration missions to the Mars system1, other planetary exploration missions to the Moon and asteroids, and space astronomy missions have yielded scientific insights and technology demonstrations that are useful to planning an MSR campaign.These missions have advanced our understanding of our Solar System and the Universe and also have matured critical technologies applicable to MSR. Table 2-1 provides an overview of these technologies. The iMARS WG Phase 2 has also considered the results of multiple studies and related technology developments that have significantly increased understanding of how to execute an MSR campaign.TABLE 2-1: Technologies applicable to MSR.TechnologyMissionApplicability to MSRGuided entry into Mars atmosphereMars Science Laboratory (NASA)The spacecraft’s descent into the martian atmosphere was guided by small rockets on its way to the surface, controlling the spacecraft’s descent until the rover separated from its final delivery system, the sky crane. This landing technique allows landing larger and more capable rovers carrying more science instruments.Sky crane terminal descentMars Science Laboratory (NASA)With spacecraft velocity close to zero, the sky crane lowered the rover to the surface from the descent stage. At touchdown, the descent stage separated from the lander and flew away, allowing the landed system to begin its missionMulti-Mission Radioisotope Thermoeleic Generator (MMRTG) for roversMars Science Laboratory (NASA)MMRTGs are a new generation of long-lived, reliable nuclear power systems ideally suited for missions involving autonomous operations in the extreme environments of space and on planetary surfaces. They reliably convert heat into electricity, generate power in increments (100+ Watt), optimize lifetime power levels (14+ years), minimize weight and ensure a high degree of safety.DrillingMars Science Laboratory (NASA)MSL’s Powder Acquisition Drill System can acquire powdered rock samples from up to 5 cm inside the surface of a rock. This system is part of the Sample Acquisition, Processing and Handling subsystem.Rosetta/Philae (ESA)Philae’s Sample Drill and Distribution system includes an integrated drill, sampler tool, and a carousel designed to collect soil samples at depths of up to 230 mm.Asteroid sample return (EEV)Hayabusa (Japan)Hayabusa performed “touch-and-go” landing on asteroid Itokawa and return samples.Rendezvous with small bodyRosetta (ESA)The Rosetta mission soft-landed its Philae probe on comet 67P/Churyumov-Gerasimenko – the first comet landing in history.Hayabusa (JAXA)Hayabusa performed “touch-and-go” landing on asteroid ItokawaTABLE 2-2: MSR science objectives as defined in McLennan et al. (2011).PriorityObjective Reference #Objective Description1A1Critically Assess any evidence for past life or its chemical precursors, and place detailed constraints on the past hability and the potential fr preservation of the signs of life2C1Quantitatively constrain the age, context and process of accretion, early differentation and magmatic and magnetic history of Mars,3B1Reconstruct the history of surface and near-surface process involving water.4B2Constrain the magnitude, naturem timing, and origin of past planet-wide climate change.5D1Assess potential environmental hazards of future human exploration.6B3Assess the history and significance of surface modifying process, including, but not limited to: impact, photochemical, volcanic, and aeolian.7C2Constrain the origin and evolution of the martian atmosphere, accounting for its elemental and isotopic composition with all inert species.8D2Evaluate potential critical resources for future human explorers. AdditionalA2Determine if the surface and near-surface materials contain evidence of extant life.Figure 2-2, reproduced here from McLennan et al. (2011), illustrates how prioritised scientific objectives guide MSR architecture, demonstrating how science drives engineering requirements.FIGURE 2-2: Science objectives and engineering implications (McLennan et al., 2011 – Note: This report assumed a 2018 launch date for a sample caching rover; hence, the date indicated in the figure).2.3 Science Objectives and Engineering ImplicationsAs outlined in the E2E-iSAG report (McLennan et al., 2011), top-level science objectives for MSR are presented in Table 2-3. Figure 2-2, reproduced here from McLennan et al. (2011), illustrates how prioritised scientific objectives guide MSR architecture, demonstrating how science drives engineering requirements.TABLE 2-3: E2E-iSAG scientific aims, as outlined in McLennan et al. (2011).Top-Level Scientific AimCandidate sample attributesA. LifeAny rocks/material preserving primary textures and sedimentary structures, in order to map different layered deposits.B. SurfaceDifferent samples isolated from each other, fresh samples below recent rinds, preservation of stratigraphic orientation for each sample.Visit Noachian/Hesperian region of interest.C. Planetary EvolutionIgneous texture and distribution of elements (spatial resolution), orientation to Martian surface (paleomagnetic samples) and isolation from magnetic fields. Visit Noachian and early Hesperian igneous outcrop. Atmospheric samples.D. Human ExplorationAirfall dust (biohazard, hazard to equipment), surface soil, shallow subsurface soil, regolithThese high-level scientific objectives require sampling from multiple regions of interest (ROIs) on the surface of Mars and thus landing in proximity to an ROI. Scientific objectives drive specific requirements for mobility, sampling and storage. Three different types of samples would be needed to fulfil these scientific objectives (McLennan et al., 2011, Table 6): rock, regolith, and atmospheric.Engineering implications of these desired sample types are: Landing site, landing ellipse, rover mobility and lifetime: Assuming the candidate landing sites identified in the E2E-iSAG report, finding relatively unaltered igneous rocks requires rover mobility and sufficient operational lifetime to reach regions of interest outside of the landing ellipse. Reducing the landing ellipse could reduce traverse distances and mission lifetime requirements.In-situ measurement: The sample-collecting rover must be capable of observing and measuring the kinds of geologic features (and variations therein) that would enable investigators to choose appropriate sampling targets.Regolith samples: Regolith samples should be collected from the top five centimetres of the surface, at a distance far enough from the lander to avoid any physical contamination by the landing event. Airfall dust should be collected separately from regolith samples.Subsurface access: Subsurface sampling would be scientifically valuable due to the possibility of enhanced preservation of organics.Replacement of collected samples: The scientific value of sample collection would be significantly enhanced if the sampling rover were capable of replacing at least 25 percent of samples collected earlier with samples of higher value collected later.Sample storage and lifetime: Storing samples on Mars, perhaps for many years, and transporting them to Earth will require sample containers to be sealed. Individual sample tubes must be sealed, and the sample return canister must be sealed before leaving Mars to avoid a significant pressure differential across sample tube seals during transit.Sample preservation: Samples delivered to Earth must retain the physical and chemical characteristics they had at the time of collection. Samples must preserve igneous texture and distribution of elements (spatial resolution), orientation to the martian surface (paleomagnetic samples), isolation from magnetic fields (isolate samples from each other), and stratigraphic orientation. Samples must be returned free of contamination.Number of samples, sample size, and total mass: To achieve the proposed science objectives, 30-35 samples are desired. The target mass of an individual samples is about 15 g. The total mass of returned samples should be at least 500 g.Atmospheric samples: The objective is to collect at least one atmospheric sample of 50 cm3 at Mars ambient atmospheric conditions. If two atmospheric samples are taken, one should be collected at the atmospheric pressure minimum and the other at the pressure maximum. Atmospheric temperature and pressure should be measured at the time of sampling. The gas container should maintain a gas-tight (ultra-high-vacuum quality) seal.2.4 Top-Level Campaign RequirementsIn translating science requirements to design specifications, the iMARS WG Phase 1 report outlined minimum top-level MRS Campaign Requirements (CRs), which apply to campaign elements but are independent of architectural implementation. They are:CR-1 MSR shall collect samples of rock, granular materials (regolith, dust) from various regions of scientific interest, and atmospheric gas.A sample-collecting rover shall be able to travel sufficient distance to reach each region of scientific interest and including a sample collection system capable of collecting multiple samples in diverse material.CR-2 MSR shall collect in-situ information for sample selection and establishment of its geological context.The sample collection element of the MSR campaign shall include multiple instruments, including at least microscopic imager, to conduct the elemental chemistry and mineralogy analyses required to select samples of interest.CR-3 MSR shall return to Earth a minimum of 500 g sample mass.This is the recommendation of MEPAG ND-SAG (2008) based on analysis of meteoritic sample investigations and reaffirmed by the E2E-iSAG (McLennan et al., 2011).CR-4 MSR shall maintain the scientific integrity of samples from collection on Mars through containment on Earth.MSR systems in contact with samples shall be designed to meet science requirements for sample preservation (e.g., temperature range, radiation levels, shocks, pressure) as well as integrity and cleanliness. MSR shall also preserve sample properties over extended storage durations, by hermetic sealing of samples.CR-5 All MSR flight and ground elements shall meet planetary protection requirements for Category V, restricted Earth return, established by COSPAR (see Appendix 6.2).This requirement originates from COSPAR planetary protection policy (Kminek and Rummel, 2015). COSPAR policy is the baseline for applicable NASA and ESA planetary protection requirements (NPR 8020.12D, 2011; ESSB-ST-U-001). Policy and requirements will be updated in response to expert recommendations, for example, from: The European Science Foundation (Ammann et al., 2012): the probability that a single unsterilized particle of 0.01 micron (previous standard, 0.2 micron) is released in the terrestrial biosphere shall be less than 1x10-6; andThe U.S. National Research Council (NRC, 2009). NASA and ESA planetary protection advisory groups have endorsed the NRC’s latest recommendations, and ESA is already applying them in developing MSR technologies.The sience definition team to be established for the MSR campaign will elaborate the details of sample collection, location and characterisation for CR-1 and CR-2 and preservation of sample integrity as per CR-4.2.5 Mars Sample Science and Planetary Protection Considerations2.5.1 Probability of Extant Life in Returned SamplesExtant life detection is not among top science priorities described by E2E-iSAG (McLennan et al., 2011), and the MSR campaign will not be optimized for life detection. However, returned samples will undergo a battery of life detection tests to meet planetary protection requirements. Thus, planetary protection measurements can be considered a necessary but largely insufficient use of Mars samples.E2E-iSAG determined that the geological context for possible extant life on Mars was insufficiently understood to plan a sample return mission focused on extant life detection. However, the likely geological context for possible fossil life on Mars is much better understood from terrestrial experience and Mars exploration to date (e.g., Grotzinger et al., 2014). E2E-iSAG thus recommended that a sample return campaign should focus on the search for fossil evidence of ancient life and its prebiotic precursors.Nonetheless, returned samples must be treated as if they might contain extant life in order to protect terrestrial life from any possibility of contamination by extraterrestrial life. Should planetary protection protocols applied to samples generate a positive detection, a new task committee should be formed immediately to revisit and revise sample management recommendations made in this report.The sample management plan described in this report provides new guidelines for scientific use of samples to meet primary goals for MSR, consistent with meeting planetary protection requirements.2.5.2 Avoiding the “Stuck in Containment” ScenarioA returned-sample management plan will need to assess the timeline within which samples can be made available to the wider scientific community. Previous studies have recommended that samples be released as soon as it is safe to do so to minimise the potential of a “stuck in containment” scenario whereby external scientists would be restricted or even prohibited from accessing samples for investigation (iMARS WG, 2008).Scientists now recognise that sample analyses required to meet planetary protection requirements are more or less the same ones they would want to perform in the interest of scientific investigation (Allwood et al., 2013; Kminek et al., 2014). Thus, the scientific benefits of planetary protection measurements are immense (e.g., Summons et al., 2014). Consequently, the recommended sample management plan encourages providing external scientists access to samples while still in containment.As measurements are made to meet planetary protection requirements, the likelihood of finding extant life and the likelihood of destroying extant life by sterilisation of samples diminish in lock step. While possible risks to safety and science must be balanced, those risks decrease greatly with each subsequent negative result. Thus, it is possible that upon completion of some set of minimum planetary protection measurements, external scientists’ access to samples could be expedited.One way to expedite access could be to have a “rolling release”, by which samples deemed safe (by testing or sterilisation) are released while more proble