TAPER Technology Advancing Phobos Exploration and Return March 29, 2013 Contents List of Figures ...................................... v List of Tables ....................................... viii Glossary ......................................... ix Team Explorer ...................................... xii Abstract .......................................... xi 1 Introduction ..................................... 1 1.1 ProblemStatement ............................... 1 1.2 Inspiration.................................... 2 1.3 Context ..................................... 2 1.3.1 TheCurrent andFutureState ofSpace Exploration . ...... 2 1.3.2 MajorContributors . 3 1.3.2.1 SpaceAgencies. 3 1.3.2.2 ThePrivateSpaceIndustry. 3 1.3.3 StepTowardsHumanExplorationofMars . 4 2 TAPER Program Overview ............................. 5 2.1 TechnologyDemonstrations . 6 2.1.1 KnowledgeGaps ............................ 6 2.1.2 ExpectedResearch . .. .. .. .. .. .. .. 7 2.2 PrecursorMission:TAPER0 . 8 2.2.1 TechnologyDemonstrations . 8 3 TAPER 1 Mission Overview ............................. 10 3.1 MissionStatement................................ 10 3.2 PrimaryObjectives ............................... 10 3.3 SecondaryObjectives .. .. .. .. .. .. .. .. 10 3.4 Requirements .................................. 11 3.5 MissionArchitecture .. .. .. .. .. .. .. .. 12 3.6 MajorDesignChoices.............................. 13 3.6.1 Phobosvs.Deimos ........................... 13 3.6.2 Conjunctionvs.OppositionClass . 14 3.6.3 LaunchDates .............................. 15 3.6.4 VehicleSelection . 16 i CONTENTS 3.6.4.1 DeepSpaceHabitat . 16 3.6.4.2 CrewVehicle. .. .. .. .. .. .. 17 3.6.4.3 PhobosExplorer . 18 3.6.5 PropulsionSystemSelection . 19 4 Science ........................................ 21 4.1 Context ..................................... 21 4.2 Science Objectives for Surface Operations . ........ 21 4.2.1 MissionCriticalScienceObjectives . .... 22 4.2.2 Additional high-priorityscience objectives . ......... 24 4.3 LandingSites .................................. 24 4.4 SciencePayload................................. 25 4.4.1 Insituinstruments . .. .. .. .. .. .. .. 25 4.4.2 Additionalscienceinstruments . ... 28 4.5 OpportunitiesforSciencewhileinTransit . ........ 29 4.5.1 In-flightsampleanalysis . 29 4.5.2 Radiationexperiments . 30 4.5.3 Intransitastrophysics. 30 5 Operations ...................................... 31 5.1 PhaseI:LEOAssemblyOperations. ... 31 5.2 PhaseII:PhobosTransitOperations . ..... 31 5.2.1 CrewActivities ............................. 31 5.3 PhaseIII:PhobosVicinityOperations . ...... 33 5.3.1 SurfaceControlOperations. 33 5.3.2 RemoteControlOperations. 35 5.4 PhaseIV:EarthReturnOperations . .... 35 5.5 PhaseV:SustainedPhobosScience. .... 36 6 Engineering ...................................... 37 6.1 Launch...................................... 37 6.1.1 Overview ................................ 37 6.1.2 LaunchVehicle(s). 37 6.2 Transit...................................... 38 6.2.1 OutboundCrewTrajectory . 39 6.2.1.1 InterplanetaryTrajectory . 39 6.2.1.2 MarsIntermediateOrbit . 44 6.2.1.3 PhobosOrbit ......................... 47 6.2.2 InboundCrewTrajectory . 48 6.2.2.1 MarsVicinity. 48 ii CONTENTS 6.2.2.2 InterplanetaryTrajectory . 48 6.2.2.3 AbortScenarios . 49 6.3 Re-entry..................................... 50 6.4 Spacecraft.................................... 50 6.4.1 SubsystemOverview . 50 6.4.2 Introduction............................... 50 6.4.2.1 AODCS&GNC ....................... 50 6.4.2.2 Command&DataHandling . 51 6.4.2.3 Communications . 51 6.4.2.4 ECLSS ............................ 52 6.4.2.5 Power............................. 52 6.4.2.6 Propulsion .......................... 52 6.4.2.7 StructuralDesignandLayout . 53 6.4.2.8 ThermalControl . 53 6.4.3 DeepSpaceVehicle. 54 6.4.3.1 Overview........................... 54 6.4.3.2 AODCSandGNC .. .. .. .. .. .. 56 6.4.3.3 Communications . 56 6.4.3.4 ECLSS ............................ 56 6.4.3.5 Power............................. 57 6.4.3.6 Propulsion .......................... 57 6.4.3.7 StructuralDesignandLayout . 58 6.4.3.8 ThermalControl . 60 6.4.4 PhobosSurfaceExplorer . 61 6.4.4.1 AODCSandGNC .. .. .. .. .. .. 62 6.4.4.2 Communications . 62 6.4.4.3 ECLSS ............................ 62 6.4.4.4 Power............................. 62 6.4.4.5 Propulsion .......................... 63 6.4.4.6 StructuralDesignandLayout . 63 6.4.4.7 ThermalControl . 64 6.5 RoboticAssistance ............................... 64 6.5.1 Goals .................................. 64 6.5.2 RobotOverview............................. 65 6.5.2.1 Design ............................ 65 6.5.2.2 Instruments.. .. .. .. .. .. .. 65 6.5.2.3 Operation........................... 66 6.6 ECLSS...................................... 66 6.7 RiskAnalysisandMitigation . ... 70 iii CONTENTS 6.7.1 DesignMarginsandSafetyFactors. 72 7 Human Factors .................................... 73 7.1 CrewSizeandSelection. 73 7.1.1 PhysiologicalTests . 74 7.1.2 GeneticTests .............................. 75 7.1.3 PsychologicalTests . 75 7.2 RadiationProtection. 75 7.3 Physiology.................................... 77 7.3.1 Countermeasures . .. .. .. .. .. .. .. 79 7.4 ClinicalMedicine ................................ 81 7.4.1 Telemedicine .............................. 82 7.4.2 3DMetalPrinting. .. .. .. .. .. .. .. 83 7.4.3 SurgicalSuite.............................. 83 7.4.4 Psychology ............................... 84 8 Programmatic Considerations ........................... 86 8.1 Costing ..................................... 86 8.2 Risk ....................................... 86 8.2.1 DescopeOptions ............................ 87 8.3 PoliticalSustainability . .... 87 8.4 PlanetaryProtection. 87 8.5 PublicRelationsandOutreach . ... 88 8.5.1 InternationalCubeSatDesignCompetition . ...... 88 8.5.2 ExternalBiologyExperiment. 89 8.5.3 AstronautInterfacing . 89 8.5.4 VehicleNaming............................. 89 8.5.5 OnlineEducation . .. .. .. .. .. .. .. 89 9 Conclusion ...................................... 91 A Answers to the Five Challenge Questions ..................... 93 B Mission Power and Link Budgets .......................... 104 C Mission Requirements ................................ 107 References ........................................ 110 iv List of Figures 1.1 ListoftechnologiesfromtheGER. .... 4 2.1 TheRoadMaptoMars.............................. 6 3.1 BATdiagramforTAPER1mission. 12 3.2 Mission ∆V and radiation estimates for different launch dates. 15 3.3 Bigelow Aerospace’s Inflatable Habitat Concept. ......... 16 3.4 Considered crew vehicles (Orion, Dragon and CTS-100). .......... 17 3.5 NASA’s Space Exploration Vehicle (SEV) Concept. ........ 18 3.6 SummaryofPropulsionTradeStudy. .... 19 5.1 Templateforatypicaldaycrewschedule. ...... 32 5.2 Template for a crew work break down for a typical day. ........ 32 5.3 Template for a crew schedule day during surface operations. ......... 33 5.4 Rendering of PSE surface operations (Photo credit: VictorDang). 34 5.5 Rendering of PSEP returning to DSV, leaving the PSE Habitat behind on the surfaceofPhobos(Photocredit: VictorDang). ...... 36 6.1 Overviewofoutboundcrewtrajectory. ...... 38 6.2 Overviewofinboundcrewtrajectory.. ...... 39 6.3 Total ∆V (in km/s, depicted in the colorbar) for Lambert Arc solutions in the year 2033 for flight times from 100 to 365 days, connecting the states of EarthandMars. ................................. 40 6.4 C3(in km2/s2, depicted in the colorbar) at Earth departure for Lambert Arc solutions in the year 2033 for flight times from 100 to 365 days, connecting thestatesofEarthandMars. 41 6.5 Total ∆V (in km/s, depicted in the colorbar) for Lambert Arc solutions in the year 2035 for flight times from 100 to 365 days, connecting the states of EarthandMars. ................................. 42 6.6 Total ∆V (in km/s, depicted in the colorbar) for return Lambert Arc solutions, given a 2033 launch year, for flight times from 100 to 365 days, connecting thestatesofMarsandEarth. 43 6.7 Arrival Earth velocity (in km/s, depicted in the colorbar) for return Lambert Arc solutions, given a 2033 launch year, for flight times from 100 to 365 days, connectingthestatesofMarsandEarth. ... 44 6.8 Total ∆V for return Lambert Arc solutions in the launch year 2035 for flight times from 100 to 365 days, connecting the states of Mars and Earth. 45 v LIST OF FIGURES 6.9 Interplanetary transfer arcs between Earth and Mars, as viewed in a Sun- centeredinertialframe. 46 6.10 Trajectory in the Martian system, viewed in a Mars-centered inertial frame. 46 6.11 Side view of trajectory in the Martian system, viewed in a Mars-centered inertialframe. .................................. 47 6.12 Representative diagram of sight access gaps from the location of the Mars- Phobos L1 to Earth during Phobos vicinity operations. Computed using STK 10......................................... 48 6.13 CAD model of assembled spacecraft, using SolidWorks. ........... 51 6.14PSEConcept. .................................. 54 6.15 ComponentMassTablefortheDSH. ... 55 6.16DSVlayout.................................... 55 6.17PowerBudgetTable. .............................. 57 6.18NTRperformance. ............................... 57 6.19HabitatLayout. ................................. 58 6.20 Crosssectionalviewofthehabitat1. ....... 59 6.21 Crosssectionalviewofthehabitat2. ....... 60 6.22Dragondesign. ................................. 60 6.23 MassbreakdownforthePSE.. 61 6.24 ECLSSpowerbudget... .. .. .. .. .. .