Refinement of Requirements for Category IVb Restricted Earth Return

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1 Planetary Protection Refinement of Requirements for Category IVb Restricted Earth Return Catharine A. Conley NASA Planetary Protection Officer Gerhard Kminek ESA Planetary Protection Officer 29 April, 2013

2 Category IVb Requirements for Mars (paraphrased) Planetary Protection Category IVb. For lander systems intended to investigate extant martian life, all of the requirements of Category IVa apply. In addition, one of the following conditions shall be met: 1. The total bioburden of the surface system is 30 bacterial spores on exposed internal and external surfaces, or at a contamination level driven by the nature and sensitivity of the particular life-detection investigations. 2. The average bioburden of the subsystems that are involved in the acquisition, delivery, and analysis of samples used for life-detection investigations is either: (a) 0.03 bacterial spores/m2, or (b) at a contamination level driven by the nature and sensitivity of the particular life-detection investigations, and recontamination prevention of these subsystems and the samples to be analyzed is in place until the end of the life-detection investigations.

3 Refining Category IVb Requirements Planetary Protection What does the requirement driven by the nature and sensitivity of the particular life-detection experiments really imply? Life detection experiments performed on Mars material returned to Earth will involve the best state-of-the-art instrumentation and capabilities available at the time Confidence in the conclusions of a life-detection protocol must be high to permit release of samples from containment Type of measurements and detection sensitivity will drive contamination limits on all elements of an MSR campaign, including initial sample caching missions

4 Returned Sample Handling Overview S A MP L E C A N ISTE R 'H E A LT H CH E C KS ' (E a rth E nt ry O K, Lan d ed S a fe ly, e tc.) TO SRF O PENING O F CANISTE R P R E L IM IN A R Y E VA LU AT IO N ( S a m p les, Gas e s, e tc.) In itia l S ub- s a m p le A ll o c a ti ons A s s e s s m en t of P re s er v a ti on Req u ire m en ts ÒPH YS ICAL/CH EM IC ALÓPRO CESS ING FURT HER ANALYTICAL TESTS C o nf ir m R e pre s en ta ti ve S a m p le S uppo rt F u rth e r Te s ti ng SAMP LE PRESERVAT IO N (P ris tin e C ura ti on ) ÒLIFE D ETE CTI ON Ó (ÒIn fo rm e dó) TE S TI N G LAT ER AN AL YS ES ÒSt er ili z a tion Óand /or "R e lea s e"? TB D CARBON CHEMIST RY? M OR P HO L OG Y? REDOX CO UPLES/ M ETAB OL IC PO SS IBILITI ES? TE RR EST R IA L B A C K G ROU N D? HERITA GE? ET C. "BI OH AZ ARD" TEST ING (Mi nim al Assum ptions & R egu la to ry Req ui re m en ts ) CHALLE NGE TES TING ON E A RT H ORG A N IS M S F un c tio na l A no m a li e s NEE D TO KNOW?! WHAT ARE TH E CO NSEQUENCES? N o L if e or Ha z ar d D et e c ted False Positives (Earth life forms ) Life on M ars All of these processes and measurements are relevant to both science and planetary protection the major difference is what each does with the information. (There are a small number of activities specific for detecting biohazards that may need to be done, but this is beyond the scope here.) P at holog ic al Ind ic at io ns N u ll T e s tin g /D ead M ar s (Toxicology?) In Vi vo vs. In Vit ro Testing H o w M a ny P hy la? Eco system T esting?

5 Draft Test Protocol Framework Table 4: Gen eral Princ ipl es Gu iding the S earch for Life: Begi n wi th a broa d s u rve y of a po rtion of d iffere nt sa m p le typ es fo r m ore gen eral featu re s su gges tive of life, t h en tu rn to a hi gh er re so lu tion exam in at ion o f sites wi th su gg estiv e fea tu res f or mo re com p lete characteriz at ion Em p hasize s tru ctu ral si gn at u res of life a nd other inh om ogeneities th at can be e asily de te cted as a f irs t o rd er ta sk Em p hasize les s d es tr u ctiv e m eth od s in th e early s ta ge s of inves tiga tion, s in ce th ey c an gu ide th e u se of m ore d efin itive b ut de st ru ctive me th od s Star t wi th sa mp les w hich a re the leas t likel y t o cont ain li fe (e.g., su rfac e fi nes); if negativ e, u se th ese as bl an ks a nd cont rols fo r sp ikin g ex p eri m en ts Recognition of life will req u ir e th e c oi n cide nc e o f m u ltip le ind ep end en t sign at u res Ina ctiv e or p as t life wil l be tre at ed as p ote n tially ac tive li fe Gener alize a c arbo n -cen tered m eth od olog y to oth er c hem ical s p ecies Use a n iterat ive a pp roa ch fo r th e Life De tection p roto col Inve st sig nifican t t im e to th e de sig n of con tro ls a nd bla nks, as ea rly i n p rot oco l dev elop me nt as possible

6 PROPERTIES OF LIVING SYSTEMS (J. Farmer) Order - The structures and subsystems of living systems are highly ordered. Replication (reproduction) - Organisms replicate themselves through various methods of asexual, or sexual reproduction. Growth and development In higher organisms there is a pattern of development controlled by regulatory genes. Energy utilization - Life utilizes a broad array of processes to extract energy from its environment. Response to the environment - Organisms interact with and respond to their environment. Evolutionary adaptation - Life adapts to environmental changes over time through mechanisms of Darwinian evolution. Necessary versus sufficient all are necessary, but none sufficient.

7 Refining the Life Detection Protocol Planetary Protection The protocol addresses life based on carbon chemistry that happens at Mars/Earth near-subsurface temperatures and pressures, on human-detectable timescales. Information addressing the properties of life as defined above might be found by measuring: 1) Structure and morphology of samples, at macro and micro scales 2) Chemical composition and heterogeneity of samples 3) Environmental and thermodynamic context of samples and interesting features within Testing competing null hypotheses is an effective strategy to address both scientific and planetary protection interests. Hypotheses are: 1) There is no life in the samples. 2) There is Mars life in the samples. Data will be collected: these data may be equally relevant to science and planetary protection. Interpretation of collected data will guide policy decisions regarding sample safety and subsequent handling, as well as inform scientific research. Characterization of measurements as 'strong biosignatures,' 'possible biosignatures,' 'indicators of abiotic processes,' or 'indicators of Earth contamination' could be useful A decision analysis strategy based on Bayesian statistics could be used to direct sequences of investigations to increase confidence in conclusions as input to policy

8 Science Informs Policy Bayesian Decision Analysis Risk hazard 8

9 Initial Characterization Computed Tomography Elemental Imaging Mineralogical Analysis Stolen from UT Austin... Life Detection Workshop - Feb , 2012, San Diego, CA 9

10 Subsample Processing Past Future? Life Detection Workshop - Feb , 2012, San Diego, CA 10

11 Targeted Characterization Prepared Surface Imaging Micro-scale Probes Particle Analysis Life Detection Workshop - Feb , 2012, San Diego, CA 11

12 Example Scheme Surface contamination requirement Bulk contamination requirement 12

13 Define Requirements Today for Analyses Tomorrow... Planetary Protection Instrumentation used on returned Mars samples will be at least as sensitive as today s instrumentation Detection of organic material on surfaces can attain femptomolar/attomolar sensitivity over micron-scale spots (e.g., LDMS; other desorption techniques) Detection of organic material in bulk samples can attain parts-per-billion sensitivity (ng/g) Capabilities to verify pre-launch organic/biological cleanliness may constrain requirements in practice Provisional guidance can be derived from past and current life detection missions, but additional work is necessary to assess current capabilities and extrapolate future needs

14 Clean Sample Handling...

Planetary Protection Considerations For Mars 2020

Planetary Protection Considerations For Mars 2020 Considerations For Mars 2020 Catharine A. Conley 13 Nov., 2013 1 COSPAR Policy for Restricted Sample Return and Guidelines for Mars... absolute prohibition of destructive impact upon return, the need for