Venus&Explora.on&Priori.es&for&

Understanding&Tectonic&and&

Geodynamic&Evolu.on&

Lori&S.&Glaze,&NASA&GSFC&E&VEXAG&Chair&

6&May&2015&

What’s&a&VEXAG?&•  VEXAG&=&Venus&Explora.on&Analysis&Group&•  CommunityEbased&forum&intended&to&provide&scien.fic&input&and&technology&development&plans&for&Venus&explora.on&over&the&next&several&decades.&&

•  Supported&by&NASA&Planetary&Science&Division&•  Sponsors&workshops&like&this&one&to&advance&science&•  VEXAG&regularly&assesses&Venus&explora.on&goals,&scien.fic&objec.ves,&inves.ga.ons,&and&cri.cal&measurement&requirements,&and&provides&input&to&the&NRC&Decadal&Survey&&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 2&

But&first,&a&commercial&message…&•  VEXAG&would&like&to&host&the&presenta.on&materials&from&this&mee.ng.&Will&get&your&permission&and&can&post&a&redacted&version&if&you&like.&

•  Upcoming&Compara.ve&Climates&of&Terrestrial&PlanetsE2&Conference&

– Would&love&to&have&a&talk&summarizing&the&results&of&this&mee.ng!&

–  Subtheme:&“Insights&Toward&Climate&Systems&Science&&&Climate&Evolu.on”;&encourage&others&to&submit&as&well&

–  Abstract&deadline:&May&15&(next&Friday)&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 3&

•  S.ll&many&unanswered&ques.ons&(Sue’s&talk)!!&&

•  Deciphering&the&tectonic&regime&and&heat&dissipa.on&mechanisms&on&Venus&are&cri.cal&to&understanding&how&and&why&Venus&is&so&different&from&Earth&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 4&

Venus:&Key&to&Terrestrial&Planets&

•  Planetary&Decadal&Survey&provides&a&framework&for&priori.es&

•  VEXAG&builds&on&those&priori.es&to&iden.fy&more&specific&Goals,&Objec.ves,&and&Inves.ga.ons&needed&to&beker&understand&Venus&and&to&place&Venus&into&context&within&the&solar&system&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 5&

Priori.es&for&Venus&Explora.on&

Goals,&Objec.ves,&&&Inves.ga.ons&•  VEXAG&“Goals,&Objec.ves,&and&Inves.ga.ons”&(GOI)&&were&compiled&based&on&broad&community&input&

•  GOI&is&periodically&updated&•  Significant&update&in&2014:&–  Restructured&the&top&level&goals&–  Assessed&priori.es&–  Substan.al&community&review&and&feedback&process&

•  Roadmap&and&Technology&plan&were&developed&in&parallel&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 6&

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Venus Technology Plan

May 2014

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Roadmap for Venus Exploration

May 2014 �����������������������������

Goals, Objectives, and Investigations for

Venus Exploration May 2014

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5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 7&

All&available&on&the&VEXAG&website:&

hkp://www.lpi.usra.edu/vexag/&

&

2014&GOI&•  Three&top&level&Goals&are&not&priori.zed:&

I.  Understand&atmospheric&forma.on,&evolu.on,&and&climate&history&of&Venus&

II.  Determine&the&evolu.on&of&the&surface&and&interior&of&Venus&

III.  Understand&the&nature&of&interiorEsurfaceEatmosphere&interac.ons&over&.me,&including&whether&liquid&water&was&ever&present&

•  Objec.ves&are&in&priority&order&within&each&Goal&•  Inves.ga.ons&are&in&priority&order&within&each&Objec.ve&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 8&

Goal&II:&Evolu.on&of&Surface&and&Interior&&Objec&ve(A( Inves&ga&on((abridged)(

•  How&is&Venus&releasing&its&heat&

and&how&is&this&related&to&

resurfacing&and&outgassing&?&

•  Has&the&style&of&tectonism&or&

resurfacing&varied&with&.me?&

•  Did&Venus&ever&experience&a&

transi.on&in&tectonic&style&from&

mobile&lid&tectonics&to&stagnant&

lid&tectonics?&&

1.&Characterize&stra.graphy&and&deforma.on&

2.&Measure&radiogenic&4He,&40Ar,&and&Xe&isotopic&ra.os&

to&determine&interior&outgassing&over&.me&

3.&Characterize&structure,&dynamics,&and&history&of&the&

interior&

4.&Determine&contemporary&rates&of&volcanism&and&

tectonic&ac.vity&

5.&Determine&absolute&ages&for&rocks&at&loca.ons&that&

are&key&to&understanding&geologic&history&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 9&

Goal&II:&Evolu.on&of&Surface&and&Interior&Objec&ve(B( Inves&ga&on((abridged)(

•  How&did&Venus&

differen.ate&and&evolve&

over&.me?&

•  Is&the&crust&nearly&all&

basalt,&or&are&there&

significant&volumes&of&more&

differen.ated&(silicaErich)&

crust?&

1.Determine&the&elemental&composi.on,&mineralogy,&and&

petrography&of&surface&samples&at&key&geologic&sites&

2.&Determine&composi.onal&informa.on&for&rocks&at&large&

scales&

3.&Determine&the&structure&of&the&crust&

4.&Determine&the&size&and&state&of&the&core&

5.&Evaluate&the&radiogenic&heatEproducing&element&content&

of&the&crust&

6.&Characterize&subsurface&layering&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 10&

Roadmap&for&Explora.on&•  Roadmap&iden.fies&poten.al&mission&concepts&in&three&Mission&Timeframes,&based&primarily&on&technology&readiness:&–  NearEterm&(this&decade)&

– MidEterm&(next&decade)&&

–  FarEterm&(beyond&2025)&

•  Roadmap&does&not&preclude&competed&opportuni.es,&interna.onal&collabora.ons,&or&combina.ons&of&elements&to&form&larger&“flagship”&missions&

•  Geodynamics&figures&prominently&in&the&Roadmap&for&Venus&Explora.on&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 11&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 12&

Roadmap&for&Explora.on&

•  Roadmap&iden.fies&poten.al&mission&concepts&

in&four&“explora.on&domains”:&

– Atmospheric&Composi.on&

– Atmospheric&Structure&and&Circula.on&

– Surface&Composi.on&and&Morphology&

–  Interior&Structure&and&Ac.vity&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 13&

Objec.ves&for&Interior&Structure&and&Ac.vity&

•  Major&outstanding&ques.ons&including&understanding:&–  How&Venus&formed&and&ini.ally&evolved&

–  How&its&interior&dynamics&may&have&differed&in&the&past&and&whether&it&ever&had&plate&tectonics&

–  The&nature&of&current&and&past&volcanic&and&tectonic&ac.vity&and&what&roles&volcanism&tectonics,&and&vola.les&play&in&current/past&heat&loss&and&vola.le&evolu.on&

– Whether&there&is&extensive&silicaErich&crust,&implying&substan.al&crustal&water&in&the&past&

–  The&planet’s&spin&state&(rota.on&and&polar&wander)&and&how&it&correlates&to&models&of&the&interior&and&its&evolu.on&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 14&

Example&Mission&Modes&E&1&

•  Orbiter&with&ac.ve/passive&remote&sensing:&

– Topography&– Radar&imaging&with&polarimetry&

– Global&gravity&– Emissivity&(microwave/IR)&

•  Can&be&done&in&the&nearEterm;&instrument&and&implementa.on&technologies&are&currently&available&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 15&

Example&Mission&Modes&E&2&•  Geophysical&lander&with&~1&Venus&year&life.me&

–  Seismology&over&a&large&frequency&range&to&constrain&interior&structure&

–  Heat&flow&to&discriminate&between&models&of&current&heat&loss&

–  Geodesy&to&determine&core&size&and&state&

–  Electromagne.c&sounding&to&constrain&gross&interior&layering&

•  Technologies&for&extended&dura.on&(beyond&a&few&hours)&in&the&surface&environment&do&not&currently&exist.&

•  May&be&able&to&envision&a&longElived&lander&in&the&MidEterm,&but&investments&are&needed&now&for&that&to&happen&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 16&

Example&Mission&Modes&E&3&

•  Lander&network&with&a&life.me&>&1&Venus&year&

– Same&measurements&as&#2&to&higher&fidelity&

– Constrain&rate&of&seismicity&and&regional&crustal&thickness&varia.ons&

– Study&local&structure&of&specific&targets&(e.g.,&tesserae,&hotspots,&rits,&and&Ishtar&Terra)&

•  FarEterm&objec.ve&that&requires&substan.al&investments&in&technology&development&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 17&

Surface/NearESurface&Ops&on&Venus&

•  Surface&Temperature:&462&°C&

•  Surface&Pressure:&92&bar&•  Atmosphere&composi.on:&Highly&corrosive,&superEcri.cal&CO2&

•  Ligh.ng&Condi.ons:&&– Sulfuric&acid&clouds&allow&~10%&of&the&incident&solar&radia.on&to&reach&the&surface&

– Ligh.ng&is&isotropic&(no&shadows)&5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 18&

Challenges&for&Geophysical&Lander&•  Power:&&

–  Bakery&approach&is&massElimited&to&a&few&hours&

–  Solar&power&is&not&viable&at&the&surface&–  Current&RadioEisotope&power&technology&is&too&inefficient&at&Venus&

surface&temperatures&

•  Thermal:&–  Passive&cooling&solu.ons&(e.g.,&phase&change&materials)&limited&to&a&

few&hours&

–  Ac.ve&cooling&requires&power&•  Instrumenta.on/Electronics:&

–  Some&progress&has&been&made&in&highEtemperature&electronics&–&Possible&upcoming&“Extreme&Environments&Centennial&Challenge”&

–  Technologies&for&high&temperature&seismometer&have&been&demonstrated&&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 19&

Recent&Technology&Workshop&•  Instrumenta.on&and&Lab&Measurements&Workshop&held&at&Langley&April&7E8&

•  Heard&about&lots&of&clever&ideas:&–  HighEtemperature&capable&microelectronics&based&on&arrays&of&carbon&nanotubes&

–  Unspooling&power&generator&(tethered&balloon&in&wind&field)&

–  Thermoacous.c&S.rling&Heat&Engine&for&cooling&and&power&

–  Al.tude&cycling&balloons&–  Gliders&that&can&“dip&down”&to&low&al.tudes&&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 20&

•  ESA’s&Venus&Express&ended&its&almost&9&year&mission&in&January&2015&

•  JAXA’s&Akatsuki&2nd&akempt&to&go&into&orbit&in&December&2015&

•  Focus&on&atmospheric&dynamics&

•  Nothing&else&“on&the&books”&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 21&

Current&Status&

•  Russia&and&India&thinking&about&Venus&

•  Both&ESA&and&NASA&offer&periodic&compe..ve&opportuni.es&to&propose&innova.ve&missions.&

•  ESA’s&Cosmic&Vision&–  MEclass&(medium&size)&

–  LEclass&(larger&size)&•  NASA&

–  Discovery&(medium&size;&every&~3&yrs)&

–  New&Fron.ers&(larger&size,&prescribed&science&objec.ves)&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 22&

What’s&Next&in&Venus&Explora.on?&

•  Medium&(M)Eclass&concept:&EnVision&orbiter&

•  Study&past&and&current&rates&and&styles&of&geologic&ac.vity&(radar&imaging,&topography,&and&surface&change,&IR&imaging,&ground&penetra.ng&radar)&

•  Spa.al&and&temporal&varia.on&of&trace&gases;&signs&of&ac.ve&volcanism&

•  Unfortunately&not&selected&in&most&recent&round&–&Next&.me!&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 23&

ESA’s&Cosmic&Vision&

R.&Ghail&–&this&session&

NASA&Discovery&Program&•  28&proposals&to&des.na.ons&throughout&the&solar&system&are&currently&under&review&

•  4&Venus&mission&concepts&&–  3&orbi.ng&radar&missions&focused&on&answering&major&geophysical&ques.ons&

–  1&in&situ&atmospheric&mission&focused&on&answering&fundamental&ques.ons&of&atmospheric&origin&&&evolu.on&and&history&of&water&

•  Step&1&selec.ons&of&3E5&concepts&expected&in&September&2015&–&stay&tuned!!&

•  Step&2&selec.on&of&ONE&mission&in&&~September&2016&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 24&

NASA’s&New&Fron.ers&•  Venus&In&Situ&Explorer&is&one&of&5&recommended&

missions;&primary&objec.ve&defined&by&NASA&

Planetary&Decadal&Survey&is&to&characterize&the&

physics&and&chemistry&of&the&crust.&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 25&

Surface&and&Atmosphere&

Geochemical&Explorer&(SAGE)&

(Larry&Esposito,&PI)&

&

New&Fron.ers&Mission&

proposed&in&2009&

&

Next&Call&September&2016&

&

•  NASA&Venus&Flagship&–&two&op.ons&have&been&examined:&

–  Venus&Flagship&study&(2009):&orbiter&with&surface&and&

atmosphere&science,&2&balloons&

and&2&landers&

–  Venus&Climate&Mission:&low(er)&

cost&Flagship&op.on&to&

characterize&current&climate&with&

orbiter,&balloon&and&drop&sonde)&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 26&

NASA&Flagship&

Conclusions&•  Importance&of&understanding&the&interior&and&surface&evolu.on&of&

the&terrestrial&planets&is&recognized&by&the&decadal&survey&

•  Venus&community&has&iden.fied&several&high&priority&inves.ga.ons&for&addressing&key&ques.ons&about&how&Venus&loses&its&heat&and&to&place&constraints&on&current&levels&of&ac.vity&

•  Current&technology&is&more&than&adequate&to&support&an&orbital&geophysics&mission&to&Venus&–&orbital&radar&mission&could&go&a&long&way&to&answering&many&ques.ons&

•  Major&challenges&for&longElived&landed&geophysical&missions&

•  No&Venus&missions&currently&“in&the&works”&by&NASA&or&other&space&agency&&

•  Compe..ve&opportuni.es&exist&within&NASA&(Discovery&and&New&Fron.ers)&and&ESA&(ME5)&–&Stay&tuned!!&

5/6/2015& Compara.ve&Tectonics&and&Geodynamics& 27&