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Data and instrument recovery and close out operations, 2011 Atacama Desert Expedition, Chile

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Data!and!Instrument!Recovery!and!Close!Out!Operations,!
2011!Atacama!Desert!Expedition,!Chile,!Earth?Mars!Cave!Detection!Project!
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Submitted:*18*April*2011*
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J.!Judson!Wynne1,2,!Guillermo!Chong!Diaz3,!Matias!Izurieta!Grollmus4,!Lynn!Hicks5,!Jose!Luis!Jara6,!
Cristian!Tambley7!and!Nathalie!A.!Cabrol1!
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1SETI! Institute,! Carl! Sagan!Center,! Mountain! View,! CA;! 2Colorado! Plateau! Research! Station! (USGS! Affiliate)! and!
Department!of!Biological!Sciences,!Northern!Arizona!University,!Flagstaff;!3Departamento!de!Ciencias!Geológicas,!
Universidad! Católica! del! Norte,! Antofagasta,! Chile;! 4Escuela! de! Ciencias! Ambientales,! Universidad! Católica! de!
Temuco,! Chile;!5
Southeast! Georgia! Regional! Medical! Center,! Brunswick,! GA;! 6CONAF,! Reserva! Nacional! Los!
Flamencos,!San!Pedro!de!Atacama,!Chile;!and,!7CampoAlto!Operaciones,!Santiago,!Chile.!
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1.0!Introduction!
Caves! on! Earth! offer! microclimates! that! can! support! extremophyllic! organisms! and! may! contain!
evidence! of! extinct! life! forms.! On! Mars,! because! caves! are! features! that! may! offer! protection! from!
harsh!surface!conditions,!they!are!important!sites!to!search!for!extinct/!extant!life!forms.!Additionally,!
these! protected! environments! may! serve! as! locations! for! habitats! or! shelters! for! future! human!
exploration.! However,! before! we! can! select! Martian! caves! for! exploration,! we! must! develop! an!
understanding! of! terrestrial! cave! thermal! behavior! and! how! thermal! properties! may! influence! the!
thermal! s ignature! associat ed! with! the! entran ce.! This! will! ultim ately! enable! us! to! d ifferentiate! caves !
from!non‐cave!anomalies!(shallow!caves!or!shelters)!and! develop!a!protocol!to!accurately!target! cave!
sites!for! exploration!is!a!prerequisite!to!any! future!mission!planning.!Caves! with!large! volume!will! be!
the!highest!priority!targets!for!NASA.!
Research ers! are! actively! d eveloping! tech niques! to! unders tand! how! to! det ect! caves! on! Eart h! and!
Mars,! and! searching! for! caves! and! cave‐like! features! on! Mars! using! remote! sensing! analytical!
techniques.!Rinker! (1975)!and! Wynne!et!al.! (2007,!2008a,!2008b,!2009)!have!improved!our! ability!to!
detect!caves!on!Earth.!Cushing!et!al.!(2007,!2008)!has!analyzed!thermal!and!visible!imagery!to!examine!
cave‐like! features! on! Arsia! Mons,! Mars.! Keszthelyi! et! al.! (2007)! has! identified! lava! tube! remnants,!
Cushing! et!al.! (2007,!2008)!have! identified! pit!craters,!and! Cabrol! et! al.!(2009)!has! identified! at!least!
677! features! likely! associated! with! speleogenesis! including! possible! lava! tubes,! deep! cavities!
associated!with!pit!chain!morphology,!cracks!associated!with!faulting,!sink!holes,!and!volcanic!vents.!!
!
Importance*of*Martian*Caves:!(A)!Caves!may!be!important!in!the!search!for!evidence!of!extraterrestrial!
life! (Mazu r! 1978;! Boston! et! a l.,! 1992;! Grin! et! al.! 19 98;! Klein! 1998;! Bo ston! 2000;! Léveill é! and! Datta!
2009)!because! caves!offer! protection!from!inhospitable! surface!conditions! ! (Mazur!1978;!Klein!1998;!
Cabrol! et!al.! 2009).! (B)!A!manned! mission! to! Mars!will!require!access! to!significant!H2O! deposits! for!
drinking!water,!oxygen!and!hydrogen!fuel.!If!subterranean!water!deposits!exist,!caves!may!provide!the!
best! access! to! these! resources! (Baker! et! al.,! 2003).! (C)! Future! human! exploration! and! possible!
establishment! of! a! permanent! settlement! on!Mars! will! require! construction! of!living! areas! sheltered!
from! harsh! surface! conditions.! Caves! with! a! protective! rock! ceiling! would! provide! an! ideal!
environment!where!these!shelters!may!be!built!(Boston!et!al.!2003).!!
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Terrestria l* Cave* Detection:! R inker! (1975)! dev eloped! a! baseline ! understanding! fo r! detecting! caves! in !
the! thermal! infrared! and! suggested! caves! could! be! detected! by! identifying! the! thermal! signal!
associated! with! the! mass! of! air! at! the! entrance! contrasted! against! the! surrounding! ground! surface.!
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(2008a,2008b)suggestthebasisforcavedetectiontemperaturewillbethecontrastbetweentherock
wallswithinthecaveentranceandexternalsurfacerock.
SinceRinkers(1975)seminalwork,advanceshavebeenmadeinterrestrial cave detection.
Wynne et al. (2009) have shown it is possible to differentiate caves from cave‐like anomalies.
However, it should be noted these results are preliminary, and a much larger sample size will be
requiredtodemonstratethefeasibilityofthistechnique.
CaveDetectiononMars: Atmospheric andsurface conditionson Mars fluctuatemore dramaticallyas
compared to Earth. On Mars, large diurnal (Kieffer et al. 1976;Yeetal.1990)andseasonal
temperature variations (Larsen et al. 2002) have been documented. Additionally, Martian air has
lowerpressure,density,andheatcapacitythanEarth's atmosphere.Thus,muchlargeramplitudesof
diurnal and seasonal temperature shifts are expected on Mars. Because these shifts would occur
widelyandinternalcavetemperatureisexpectedtoberelativelyconstant, Martian cavedetectionis
feasibleusingimageryattheappropriatewavelengthandspatialresolution(Wynneetal.2008a).We
anticipatethis willinfluencesignalstrength ofMartiancaveentrancesresultinginastrongerthermal
signalthantheirterrestrialcounterparts.
2008AtacamaDesertExpeditionAccomplishments:We(1)deployedtemperatureandbarometric
pressuredataloggersatninecavesandsixcave‐likeanomaliesandonthesurfaceadjacenttoallstudy
sitesin the AtacamaDesert, northern Chile,(2) developedcartographic techniques forderiving cave
volume,and(3)mappedtwocavesandtwonon‐cavefeaturesusingtraditionalcartographic(referto
Dasher 1994) and newly developed volumetric techniques. Refer to Wynne et al. (2008c) for more
information.
2009AtacamaDesertExpeditionAccomplishments:We (1) retrieved datafromdataloggerslocatedat
all study sites; (2) relaunched and redeployed all data loggers; (3) analyzed data and determined
sensorplacementwascorrectforallstudysites;and,(4)mappedandcollected volumetricdataatsix
cavesandtwonon‐caveanomalies.RefertoWynneetal.(2009)formoreinformation.
GoalsandHypotheses:Ouroverallprojectgoalsareto(1)betterunderstand thermalbehaviorofboth
terrestrialandMartiancaves,theiroptimaldetectiontimeofdayandseason;andto(2)ultimatelybe
able to differentiate caves from non‐cave features, and potentiallyinferringcavevolumefromthe
thermal signal of a cave entrance. To that end, our project will test several hypotheses: (A) Cave
structure,geospatiallocation, topographyandgeologywillinfluencethermalcapacityandaffectcave
signature, thus detection capabilities in the thermal infrared; (B) Strength of thermal signal of cave
entrancesisdirectlycorrelatedtovolumeandhorizontallength; (C) Non‐cave features will have
thermalbehaviorsdistinctfromcaveentrances,enablingustodiscern caves from non‐cavefeatures;
and,(D)DuetothelowatmosphericpressureandwidediurnaltemperaturefluctuationsonMars,we
expectsignalstrengthofcaveentrancestobestrongerascomparedtoEarth.
2011MissionObjectives:ThiswasourfinaltriptotheAtacamaDesertforthisproject.Ourobjectives
were to (1) confirm the locations of all instruments deployed within caves and on the surface (2)
retrieveallinstrumentsfromallstudysites,and;(3)uploaddatafromallinstruments.
2.0Methods
StudyArea:We selected caves in the Atacama Desert of northern Chile due to the region's hyper‐
aridityanddramaticdiurnaltemperaturefluctuations,whichmakethisareaanidealanalogforMars.
RecentstudiessuggestthattheAtacamahasbeenaridfor90Ma(e.g.,HartleyandChong2002;Hartley
etal.2005),andregionswithinthedeserthavebeenhyper‐aridfor10‐15Ma(Ericksen1983;Berger
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and Cooke 1997; Houston and Hartley 2003). The level of rain in the hyper‐arid core is virtually
indistinguishablefromzero;however,thisregionmayhavebeenamuchwetterplace‐muchlikeMars
(e.g.,Chong1984,1988;Navarro‐Gonzalezetal.2003;Quinnetal.2005).
Vegetationcoversurroundingmostofourstudysitesislowtonon‐existent.Thiswasanimportant
considerationbecausevegetationcoverwillconfoundourabilitytoeffectivelymeasurethedifferences
betweenentranceandsurfacetemperatures.
Surfacematerialnearthecaveentranceswasmoderate‐to‐looselyconsolidatedalluviumcomprised
ofsiltyloamandclayswithgraveltobouldersizedsandstone, shale and volcanic clasts. Due to the
looselyconsolidatednatureofthesurface,weexpectthesurfacethermalinertiatobelow—resulting
inrapidwarmingduringthedayandrapidcoolingfollowingsunset.However,consolidationandrock‐
sizedistributionsof surface materialvariesfrom site to site,andthus,the thermal inertia associated
withthesematerialswillalsovary(e.g.,PresleyandChristensen1997).
ConfirmingGPSLocationsofSurfaceInstruments:Weused a Garmin60CSxtoconfirm locations ofall
surfaceinstruments.Weusedthe“average” function to captureGPSdata.Thisfunctionenables us to
averagethenumberofGPSreadingscollectedfromdifferentsatellitestoimprovepositionalaccuracy.
Weaccepted allcoordinatedatathatwasat≤ 3meteraccuracy,andcollectedcoordinatedatavia the
“average”functionwhenaccuracywasgreaterthan3meters.
ConfirmingLocationsofInstrumentswithinCavesandNonCaveFeatures:We used a Leica Disto D3
laser distance finder to record the height of each instrument deployed within each feature. When
possible,wealsocollectedthedistancefromtheestimateddrip‐lineoftheentranceorskylight.
DataRetrieval:For H21 Micro‐stations,we used theOnset Hobo U‐Shuttleto retrievethe data.Once
datawasuploadedtotheshuttle,itwasthenuploadedtoacomputerusingHOBOWare2.7.2.ForU23
units,weusedtheHoboOpticUSBBaseStationtouploaddatadirectlytothecomputerviaHOBOWare
2.7.2.
3.0Results
ConfirmingGPSLocationsofSurfaceInstruments:Weconfirmedthelocationsofallsurface
instrumentation. We collected additional coordinate data for all instrument locations >3.0 meter.
Spatiallocationofallinstrumentsarewithin~3.0maccuracy.
ConfirmingLocationsofInstrumentswithinCavesandNonCaveFeatures:Wecollectedtheheightand
distance (when possible) of all instruments deployed within each cave and non‐cave feature. These
datawereusedtoimprovethelocationofeachinstrumentoneachmapandwillbereportedinaUSGS
OpenFileReport.
DataRetrieval:Overthethreeyearsoftheproject,weretrieveddatafrom69instrumentsfromcaves,
non‐cave features, and surface. Unfortunately, numerous instruments were stolen during field
operations.Twenty‐oneinstrumentswerestolenduringthethree‐yearlife of thisprojectresultingin
thelossof~23% of ourinstruments,andpotentially significantly hampering ourability tointerpret
thethermalbehaviorofatleastoneofourstudycaves.Oneinstrumentwasactually recovered bya
CONAFofficial,butthetemperatureprobewasseveredfromtheinstrument.Ithadonlycollecteddata
for3monthsbeforeitwasdisturbedanddamaged.

Table1.Summarytableofinstrumentsdeployedpercave/non‐cavefeatureandthestatusoftheseinstruments
bothwithinand on thesurfaceat proximity to eachfeature. Typerefersto thetypeoffeatureeither“cave” or
“cave‐likefeature.”Deployedindicatestothenumberofinstrumentsdeployedwithineachfeature.Lost/Stolen
(2009)referstothenumberofinstrumentsnotrecoveredduring2009andLost/Stolen/Damaged(2011)refers
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to the number of instruments either not recovered or damaged during 2011. Dataindicates the number of
instrumentsfor which wehavedata. Data wascollected at thiscave from 2008‐2009;instruments were then
removedfromthiscaveandredeployedatothersitestoimproveourabilityto interpretcavethermalbehavior
attheotherstudycave.
NameTypeDeployed
Lost/Stolen
(2009)
Lost/Stolen/
Damaged
(2011)Data
Chulacao Cave 17 2 5 10
Telocote Cave 11 ‐‐ 1 10
Salon Cave 15 2 1 14
Guia Cave 3 1 1 1
PaisajeSal Cave 12 1 ‐‐ 11
LunayMedia Cave 9 ‐‐ 2 7
Quitor Cave 7 1 1 5
LosGatos Cave 4 ‐‐ ‐‐ 4
Shreader Cave 12 ‐‐ 2 11
Huesos Cave‐likefeature 2 ‐‐ ‐‐ 2
Cascada
Pequeña Cave‐likefeature 2 ‐‐ ‐‐ 2
Cartape Cave‐likefeature 2 1 ‐‐ 2
MinaPequeña Cave‐likefeature 2 ‐‐ 1 1
4.0Discussion
Allmission criticalobjectives were metduring thisexpedition.Thelossofinstrumentsandthedata
stored on these instruments is disappointing, but disturbance to instrumentation in not‐so‐remote
areasisquitecommon.ACONAFofficialmanagedtorecoveroneinstrumentfromatourist’sdog‐‐the
dogwascarryingtheinstrument,severedcordandall,initsmouth.Unfortunately,theinstrumenthad
logged data for only three months before the tourist (or dog) removed the instrument from its
deployedlocation.
Through our efforts in the Atacama Desert, we will ultimately:(1) identify times when differences
between cave entrances and surface control stations are optimalandthusdetectioninthethermal
infrared is also optimal; (2) compare the thermal behavior of caves to non‐cave anomalies, and; (3)
populatesimulation modelsofthe thermaldynamics of Martiancaves andsurface.Additionally, this
projectwillresultinthe:(i)developmentof asystematicapproachforterrestrialandextraterrestrial
cavedetection;(ii)establishmentofathermalsignaturelibraryofterrestrialcavesofvariousstructure
types;(iii) designation ofoptimal times fordetection of cavesona per structurebasis for Earthand
Mars;and(iv)identificationofinstrumentationandmissionrequirementsfordetectingMartiancaves.
Acknowledgements: We extend our gratitude and thanks to Jorge Retamal Valenzuela, Eduardo
Rodguez,andTomasGeröMertenswithCONAF,andManuelCortesMora with AsociaciónIndígena
Valle de la Luna for facilitating and issuing our research permits and for supporting this work. We
thankDanRubyandTimTitusforassistancewithexpeditionplanning,DanRubyfordevelopingcave
volumemaps,RandyBertholdandtheNASAARCEERRBSafetyReview Panel for their direction
leading to the improvement of the expedition safety plan, Matt AngoffandGlobalRescuefortheir
stand‐by extrication support, the stand‐by Cave SAR team (Kyle Voyles, Jon Jasper, Shawn Thomas,
Marc Ohms and Bonny Armstrong), and Joel DeSpain and Shane Fryer for access to Atacama Desert
cave maps. Special thanks to the 2008 and 2009 Atacama Desert Expedition Teams for the
2011 Atacama Desert Expedition – Explorers Club Flag Report
5
foundationalheavy‐liftingthatledtotheultimatesuccessof workinthisregionand toTheExplorers
Club (Constance Difede and The Flag and Honors Council) for recognizing this expedition as a Flag
Expedition.WealsoacknowledgeEdmondGrin,MurzyJhabvala,JeffMoerschPeterShuandTimTitus
fortheircontinuouseffortsandcontributions to the overallobjectives of thisproject.MarianneArini
provided technical comments and editorial support. This project is supported by the NASA
Astrobiology:ExobiologyandEvolutionaryBiologyprogramundergrant#EXOB07‐0040.
Table2:2011AtacamaDesertExpeditionTeam,AffiliationsandRoles.
TeamMember Affiliation Role
JutWynne,FN’06 SETI;NAU Expeditionlead;Instrument
removal
LynnHicks,MN’08 SoutheastGeorgiaHealthSystem ExpeditionDoctor;Fieldsupport/
Instrumentremoval
JoseLuisJara CONAF FieldSupport/Instrument
Removal
MatiasIzurieta
Grollmus
UCT FieldSupport/Instrument
Removal
CarlosInaipil UCT FieldSupport/Instrument
Removal
GuillermoChong UCN Geologist;Logistics
CristianTambley CampoAltoOperaciones LogisticsChief
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ResearchGate has not been able to resolve any citations for this publication.
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