Planetary Protection

Refinement of Requirements for Category IVb

Restricted Earth Return

Catharine A. Conley NASA Planetary Protection Officer

Gerhard KminekESA Planetary Protection Officer

29 April, 2013

Planetary Protection

Category IVb Requirementsfor Mars (paraphrased)

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.

Planetary Protection

Refining Category IVb Requirements

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

T O S RF

O P E N IN G O F C A N ISTE RP 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 it ia l S ub- sa m p le A ll o c a ti ons¥ A s s e s s m en t of P re s er va ti on Req u ire m en ts

F U RT H E R A N A L Y TI C A L T E STS¥ C o nf ir m R e pre sen ta ti ve S a m p le¥ S uppo rt F u rth e r Te s ti ng

S A MP L EP R E S E R VAT IO N(P r is t in e C ura ti on )

L AT E R AN AL YS E SÒSt er ili z a t ion Ó a nd /or"R e lea se" ? TB D

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 .)

ÒL IFE D E TE C TI ON Ó(ÒIn fo rm e dÓ) TE S TI N G

C A R B O N C H E M IST R Y ?M OR P HO L OG Y ?R E D O X CO U P L E S / M E TAB OL IC PO SS IB IL ITI E S ?TE RR EST R IA L B A C K G ROU N D?H E R ITA GE ?ET C . "BI OH AZ A R D " TEST IN G

(Mi n im a l A s s u m p t io n s & R egu la to ry Req ui re m en ts )C H A L LE N G E TES T IN G O N E A RT H ORG A N IS M S

¥ F un c t io na l A no m a li e s¥ P at h o log ic a l Ind ic at io ns¥ N u l l T e s t in g /D ead M ar s

(T o xi c o lo gy ? )¥ In Vi v o v s . In Vit ro T es ti ng¥ H o w M a ny P hy la ?¥ E co sy s tem T e s t in g ?

N EE D T O K N O W? !W H A T A R E TH E CO N S E Q U E N C E S?

¥ N o L if e or Ha z ar d D et e c ted¥ F a ls e P o si t iv es (E ar th li fe f or ms )¥ L ife o n M a rs

ÒP H YS IC A L /C H E M IC A L Ó P RO C E SS IN G

Returned Sample Handling Overview

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.)

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 r tion of d iffere nt sa m p le typ es fo r m ore gen eral fea tu re ssu 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 efea tu res f or mo re com p lete charact eriz at ion

• Em p hasize s tru ctu ral si gn at u res of life a nd other inh om ogenei ties th at can be e asi ly de te ctedas a f irs t o rd er ta sk

• Em p hasize les s d es tr u ct iv e m eth od s in th e early s ta ge s o f inves tiga tion, s in ce th ey c an gu ideth e u se of m ore d efin it ive 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 a in 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 ct iv e or “p as t” life wil l be tre at ed as p o te n tially ac t ive li fe

• Gener alize a c arbo n -cen tered m eth od olog y to oth er c hem ical s p ecie s

• Use a n iterat ive a pp roa ch fo r th e Life De tect ion p roto col

• Inve st sig n ifican 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 ntas p ossible

Draft Test Protocol Framework

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.

Planetary Protection

Refining the Life Detection Protocol

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 scales2) Chemical composition and heterogeneity of samples3) Environmental and thermodynamic context of samples and interesting features

withinTesting 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 usefulA 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

hazard

Risk

Life Detection Workshop - Feb. 15-17, 2012, San Diego, CA 9

Initial Characterization

Computed Tomography

Elemental Imaging

Mineralogical Analysis

Stolen from UT Austin...

Life Detection Workshop - Feb. 15-17, 2012, San Diego, CA 10

Subsample Processing

Past Future?

Life Detection Workshop - Feb. 15-17, 2012, San Diego, CA 11

Targeted Characterization

Prepared SurfaceImaging

Micro-scale Probes

Particle Analysis

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Example Scheme

Surface contamination requirement

Bulkcontamination requirement

Planetary Protection

Define Requirements Today for Analyses Tomorrow...

• 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

Clean Sample Handling...