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From page 633... ... Appendix C Technical Risk and Cost Evaluation of Priority Missions BACKGROUND The survey's statement of task (see Preface and Appendix A) calls for "identifying, recommending, and ranking the highest priority research activities" in planetary science, astrobiology, and planetary defense. Read the entire page →
From page 634... ... 634 ORIGINS, WORLDS, AND LIFE A comprehensive review of the then most recent round of space-science decadal surveys was conducted during a workshop held in 2012 (NASEM 2013) and again in a 2015 consensus study (NASEM 2015) Read the entire page →
From page 635... ... APPENDIX C 635 NASA's key decision points KDP-B and KDP-C and design reviews such as PDR and the Critical Design Review (CDR) Read the entire page →
From page 636... ... 636 ORIGINS, WORLDS, AND LIFE TABLE C-2 Mission Concepts Considered by the Decadal Survey for Technical Risk and Cost Evaluation Name Origin Disposition Additional Information Mercury Lander PMCS Selected for TRACE NASA 2020g and Appendix C Venus Flagship PMCS Selected for TRACE NASA 2020k and Appendix C Venera D SDT Not selected for TRACE Venera-D 2019 and Appendix D VISAN: Venus In Situ PV Not selected for study or Appendix E Seismic and Atmospheric TRACE Network VSCA: Venus Sub-Cloud PV Not selected for study or Appendix E Aerobot TRACE VLP: Venus Life Potential PV Not selected for study or Appendix E TRACE VIDEO: Venus PV Not selected for study or Appendix E Investigation of Dynamics TRACE from an Equatorial Orbit ADVENTS: Assessment PV Selected for study; not NASA 2021a and and Discovery of Venus's selected for TRACE Appendix D Past Evolution and Near Term Climatic and Geophysical State Lunar Geophysical PMCS and V&V Prioritized following NASA. 2020d and Network CATE by V&V; no Appendix C of V&V further action needed Intrepid: Lunar Long- PMCS Selected for TRACE NASA 2020c and Range Rover Traverse Appendix C Endurance: Lunar South PMM Selected for study and NASA 2021f and Pole Aitken–Basin Sample two variants selected for Appendix C Collecting Rover TRACE INSPIRE: In Situ Solar PMM Selected for study and NASA 2021g and System Polar Ice Roving selected for TRACE Appendix C Explorer MOSAIC: Mars Orbiter for PMCS Not selected for TRACE NASA 2020f and Surface-Atmospheric- Appendix D Ionospheric Connections MORIE: Mars Orbiter for PMCS Not selected for TRACE NASA 2020e and Resources, Ices, and Appendix D Environments Mars Life Explorer PM Selected for study and NASA 2021h and selected for TRACE Appendix C Mars In Situ PMCS Selected for TRACE NASA 2020b, additional Geochronology detail from originating team, and Appendix C Mars Deep Time Rover PM Not selected for study; Appendix E not selected for TRACE Mars Polar Ice, Climate PM Not selected for study; Appendix E and Organics not selected for TRACE Ceres Sample Return PMCS Selected for TRACE NASA 2020h and Appendix C Cryogenic Comet Nucleus PSSSB Selected for study. Read the entire page →
From page 637... ... APPENDIX C 637 TABLE C-2 Continued Enceladus Orbilander PMCS Selected for TRACE NASA 2020a, additional details from originating team, and Appendix C Enceladus Multiple Flyby Prior study Selected for TRACE NASA 2021e and documentation Appendix C made available to survey Titan Orbiter and Probe Prior study Version without the sea NASA 2021i and documentation probe selected for TRACE Appendix C made available to survey Saturn Ring Skimmer PGPS Not selected for study or Appendix E TRACE Centaur Orbiter and Lander PSSSB Selected for study and NASA 2021c, and selected for TRACE Appendix C Uranus Orbiter and Probe PGPS and Selected for study and NASA 2021j and POWDP selected for TRACE Appendix C Calypso: Uranus Moon and PSSSB and Selected for study and NASA 2021b and KBO Flyby POWDP selected for TRACE Appendix C Odyssey: Neptune Orbiter PMCS Selected for TRACE NASA 2020i, additional and Probe details from originating team, and Appendix C Triton Ocean World POWDP Selected for study and NASA 2021k and Surveyor selected for TRACE Appendix C Persephone: Pluto System PMCS Not selected for TRACE NASA 2020j and Orbiter and Kuiper Belt Appendix D Explorer Interstellar Object Rapid PSSSB Not selected for study or Appendix E Response Mission for TRACE Solar System Space Cross-panel group Not selected for study or Appendix E Telescope for TRACE NOTES: Green, orange, and pink shading, respectively, indicate that a concept was studied and selected for TRACE, was studied but not selected for TRACE, and was suggested but not studied. PGPS, Panel on Giant Planet Systems; PM, Panel on Mars; PMM, Panel on Mercury and Moon; POWDP, Panel on Ocean Worlds and Dwarf Planets; PSSSB, Panel on Small Solar System Bod ies; PV, Panel on Venus; PMCS, Predecadal Mission Concept Study; SDT, Science Definition Teams; V&V, Vision and Voyages decadal survey (NRC 2011) Read the entire page →
From page 638... ... 638 ORIGINS, WORLDS, AND LIFE FIGURE C-1 Schematic illustration of the flow of the Aerospace Corporation's technical risk and cost evaluation (TRACE) process. Read the entire page →
From page 639... ... APPENDIX C 639 The evaluation of technology, cost, and schedule are inextricably intertwined. However, it is easier to describe each element of the overall analysis (e.g., technical, schedule, and cost) Read the entire page →
From page 640... ... 640 ORIGINS, WORLDS, AND LIFE on the information provided by the various mission study teams with a focus on treating all projects equally. To be consistent for all concepts, the TRACE cost process allows an increase in cost resulting from increased contingency mass and power, increased schedule, increased required launch vehicle capability, and other cost threats depending on the concept maturity and specific risk assessment of a particular concept. Read the entire page →
From page 641... ... APPENDIX C 641 TRACE RESULTS FOR PRIORITY MISSIONS Summaries of the results of the TRACE evaluations of the 17 priority missions identified by the decadal survey because of their potential to address the 12 key science goals (see Chapters 4 to 15) and potential technical viability presented in Boxes C-1 through C-18. Read the entire page →
From page 642... ... 642 ORIGINS, WORLDS, AND LIFE BOX C-1 Mercury Lander Scientific Objectives as Studied Geochemistry: Investigate the mineralogy and chemistry of Mercury's surface Geophysics: Characterize Mercury's interior structure and magnetic field Space Environment: Determine the active processes that produce Mercury's exosphere and alter its regolith Cruise Configuration Geology: Characterize the landing site at a variety of scales and provide context for landed measurements Landed Configuration Key Features Key Challenges Lander (10.5-yr life, 10-yr cruise, 0.2-yr orbital mission, 0.3-yr landed mission) Maintaining safe thermal control at close solar distance Payload: (11 instruments) Read the entire page →
From page 643... ... APPENDIX C 643 BOX C-2 Venus Flagship Scientific Objectives as Studied SmallSats Habitability: Understand the history of volatiles and liquid water on Venus and determine if Venus has ever been habitable Determine if Venus once hosted liquid water at the surface Identify and characterize the origins and reservoirs of Venus's volatiles today Place constraints on whether there are habitable environments on Aerobot Venus today and search for organic materials and biosignatures Orbiter Climate: Understand the composition and climatological history of the surface of Venus and the present-day couplings between the surface and atmosphere Lander Constrain surface composition and chemical markers of past and present climate Geology: Understand the geologic history of Venus and whether Venus is active today Determine if Venus shows evidence of a current or past plate tectonic regime Determine whether Venus is tectonically and volcanically active today Key Features Key Challenges Orbiter (12.4-yr life) Lander design for hazards in challenging landing environment Payload (7 instruments) Read the entire page →
From page 644... ... 644 ORIGINS, WORLDS, AND LIFE BOX C-3 Intrepid -- Long-Range Lunar Rover Scientific Objectives as Studied Evolution of the Lunar Interior and Nature of the Procellarum KREEP Terrane: Determine the cause of extended volcanism in the Procellarum region Determine the cause of the lunar crustal asymmetry Test hypotheses for the origin of non-basaltic volcanism Determine the composition of deep mantle pyroclastic deposits Determine decline of core dynamo and magnetic field over time Diversity of Styles of Magmatism: Characterize flood basalt emplacement, rilles, flows, and vents Determine origin and composition of cones, domes, and shields Characterize pyroclastic volcanism processes: composition and physical state Determine the relationship between intrusive and effusive materials Post-Emplacement Modification of Magmatic Materials: Test hypotheses of impact crater formation, ballistic sedimentation, ray formation Determine target material influence on impact crater formation Determine the causes of magnetic anomalies, swirls, and space weathering Key Features Key Challenges Rover (4-yr life) Availability of NGRTG Mod 2 in time for mission Payload: (8 instruments + retroreflector) Read the entire page →
From page 645... ... APPENDIX C 645 BOX C-4 Endurance-A, South Pole–Aitken Basin Sample Collecting Rover (Astronaut Return) Scientific Objectives as Studied Solar System Chronology: Anchor the earliest impact history of the solar system by determin ing the age of the largest and oldest impact basin on the Moon, the South Pole–Aitken basin Test the giant planet instability, impact cataclysm, and late heavy bombardment hypothesis by determining when large far side lunar impact basins formed Anchor the "middle ages" of solar system chronology (between 1 and 4 billion years ago) Read the entire page →
From page 646... ... 646 ORIGINS, WORLDS, AND LIFE BOX C-5 Endurance-R -- South Pole–Aitken Basin Sample Collecting Rover (Robotic Return) Scientific Objectives as Studied Solar System Chronology: Anchor the earliest impact history of the solar system by determin ing the age of the largest and oldest impact structure on the Moon: South Pole–Aitken basin Test the giant planet instability, impact cataclysm, and late heavy bombardment hypotheses by determining when large far side lunar impact basins formed Anchor the "middle ages" of solar system chronology (between 1 and 4 billion years ago) Read the entire page →
From page 647... ... APPENDIX C 647 BOX C-6 INSPIRE, Lunar Polar Volatiles Rover Scientific Objectives as Studied Origins: Determine the origins of volatiles in the inner solar system Determine the abundance and distribution of lunar volatiles including water by measuring sulfur-bearing molecules, isotopic ratios, carbon based molecules, and D/H ratios Use volatile distributions (lateral and vertical) and the physical form of volatiles to distinguish between sources including early outgassing, asteroid impacts, comet impacts, solar wind–regolith interactions, and ongoing small meteoroid bombardment Ages: Evaluate the timescales of volatile delivery in the inner solar system Determine the age of lunar volatiles by measuring the form and distribution and comparing with past and present-day environmental conditions Evolution: Assess how volatiles evolve on solar system airless bodies Determine how lunar volatiles have evolved over time by measuring the distribution of volatiles and correlating with environmental factors and geological context Key Features Key Challenges Rover (3-yr life) Read the entire page →
From page 648... ... 648 ORIGINS, WORLDS, AND LIFE BOX C-7 Mars In Situ Geochronology Scientific Objectives as Studied Determine the chronology of basin-forming impacts to constrain the time period of heavy bombardment in the inner solar system and thus address fundamental questions related to inner solar system impact processes and chronology Reduce the uncertainty for inner solar system chronology in the "middle ages" (1–3 Ga) to improve models for planetary evolution, including volcanism, volatiles, and habitability Establish the history of habitability across the solar system Calibrate the body-specific chronology for Mars Mars In-Situ Geochronology Lander in its Aeroshell Key Features Key Challenges Lander (40-mo life: 27.5-mo cruise, 11-mo data collection, 1.5-mo Lander mass increase impact on design of the entry, descent, and data downlink) Read the entire page →
From page 649... ... APPENDIX C 649 BOX C-8 Mars Life Explorer Scientific Objectives as Studied Search for organic molecules, non-equilibrium gases, and isotopes associated with ice and regolith, and evaluate their possible biological origin Assess the habitability of the near-subsurface environment with respect to required elements to support microbial life, microbial energy sources, and compounds toxic to microbes Quantify the down borehole thermophysical properties of the ice/ ice-cemented regolith and any role for liquid water in its creation or modification Determine the processes that preserve/modify/destroy these ice Mars Life Explorer with Drill Deployed deposits in the modern climate Key Features Key Challenges Lander (34-mo life: 10-mo cruise, 3-mo sample, 21-mo meteorology Challenge accessing near-surface ice with lander accuracy and drill only) mobility Science Payload: Biosignature Detection Suite (DRaMS w/EGA + Mini-TLS) Read the entire page →
From page 650... ... 650 ORIGINS, WORLDS, AND LIFE BOX C-9 Ceres Sample Return Scientific Objectives as Studied Test if extrusion from a brine-rich mantle occurred during Ceres's recent history Test if endogenic activity is ongoing at Occator crater Determine the depth of liquid water below Occator crater Characterize Ceres's deep brine environment at Occator crater Characterize the evolution of organic matter in long-lived brines Ceres Orbiter/Lander – Landed Configuration Determine Ceres's accretional environment Key Features Key Challenges Hybrid Orbiter/Lander (13.5-yr life, 6.3-yr outbound cruise, 1.4-yr New use of large ROSA for hybrid orbiter/lander mission orbital mission, 3-wk landed mission, 5.75-yr inbound cruise) Payload: Lack of definition for sample handling and preservation Narrow Angle Camera: Imaging at pixel scale of 1 m from 100 km altitude; includes image compression Uncertainty in sample collection requirements and approach Magnetotelluric Sounder: Determines depth-dependent e lectrical conductivity of the subsurface from frequency-dependent mag- Lack of definition for surface energy generation and usage netic and electric fields Infrared Point Spectrometer: Miniature spectrometer covering Technical Risk Rating 2–4 micron range Sampling System: PlanetVac sample collector, sample transfer Medium: Medium new development, adequate to optimistic margins, system and/or medium risk of achieving major mission objectives as proposed Flight System: 3× NEXT thruster electric propulsion, Hydra zine propellant system, powered by 95 m2 roll-out solar array (ROSA) Read the entire page →
From page 651... ... APPENDIX C 651 BOX C-10 Europa Lander Scientific Objectives as Studied Biosignatures: Search for evidence of biosignatures on Europa Identify potential biosignatures through a minimum of 9 lines of evidence: organic abundance, organic patterns, chirality, isotopes, microscale structures, macroscale structures, cellular properties, and biominerals Habitability: Assess the habitability of Europa via in situ techniques Characterize non-ice composition of Europa's near-surface material to determine whether there are environmental factors essential for life Determine the proximity to liquid water and recently erupted materials at the lander's location Surface Properties and Dynamics: Characterize the surface and subsurface of Europa Observe properties of surface materials and connect local proper ties with those seen from remote sensing Characterize dynamic processes of Europa's surface and ice shell over the mission duration Key Features Key Challenges Carrier Stage (7-yr life) Lander science operation within energy and thermal constraints Flight System: Chemical propellant system, 127 m2 solar array, X band communications, radiation vaults to protect avionics, radia- Landing safely on uneven and uncertain terrain tion TID 1.5 Mrad, Bio Barrier for Lander Long-range direct to Earth downlink of science data from lander Deorbit Stage Lander and instrument contamination control for biosignatures science Flight System: Solid rocket motor with 5,000–5,700 kN-s total im pulse, reference design based on Star-48 motor, system includes thermal and separation hardware System mass multipliers with hardware growth Descent Stage: Technical Risk Rating Flight System: Hydrazine monopropellant system with 410 kg Medium: Medium new development, adequate to optimistic margins, propellant, redundant avionics and GNC with Terrain Relative and/or medium risk of achieving major mission objectives as proposed Navigation (TRN) Read the entire page →
From page 652... ... 652 ORIGINS, WORLDS, AND LIFE BOX C-11 Enceladus Orbilander Scientific Objectives as Studied Determine If Enceladus Is Inhabited: Search for biosignatures Characterize amino acids and lipids Search for a polyelectrolyte and any cell-like morphologies Assess to What Extent Enceladus's Ocean Is Able to Sustain Life and Why: Provide geochemical and geophysical context for life detection Quantify physical and chemical environment Determine internal structure, vent structures Find Locations to Land and Actively Sample: Balance science, safety, and planetary protection Find a scientifically compelling landing site with a sufficiently high plume fallout rate Perform reconnaissance for both safe landing and active sampling Find sites with adeqVuate surface temperature to avoid melt Deployed Orbilander through ice crust Key Features Key Challenges Orbilander (10.5-yr life, 7-yr cruise, 1.5-yr orbital mission, 2-yr landed Complexity of TRN + pitch-over landing strategy mission) Payload: Lander/Instrument contamination control for life detection Life Detection: High Resolution Mass Spectrometer (HRMS) Read the entire page →
From page 653... ... APPENDIX C 653 BOX C-12 Enceladus Multiple Flyby Scientific Objectives as Studied Search for Signs of Life in Enceladus Plume Materials: Search for multiple features of life (biosignatures) Multiple, independent measurements of molecular qualities in organic compounds Assess the Habitability of the Enceladus Ocean: Quantitative measurements of key habitability parameters including sources of essential elements and micronutrients, sources of chemical energy, and key physiochemical parameters Characterize Enceladus's Cryovolcanic Activity: Observe details of the structure of Enceladus plume and how it varies in space and time, including a more precise estimation of the relative contributions of jets and curtains to the overall plume Key Features Key Challenges Flyby Vehicle (12-yr life, 9-yr cruise, 3-yr repeat flyby mission) Read the entire page →
From page 654... ... 654 ORIGINS, WORLDS, AND LIFE BOX C-13 Titan Orbiter (Sea Probe Descoped) Scientific Objectives as Studied Geology: Understand the processes actively shaping Titan's surface Geophysics: Understand Titan's interior structure and surface–interior exchange processes Astrobiology/Chemistry: Understand Titan's organic chemistry and path to prebiotic molecules Spacecraft with solar arrays extended Atmosphere: Understand Titan's climate as a source of surface modification Solar arrays eliminated to show the internal configuration of the spacecraft Key Features Key Challenges Orbiter (14-yr life: 10-yr cruise phase, 2-yr Saturn tour phase, 2-yr Titan atmosphere uncertainty impact on flight system for aerosam Titan orbit phase) Read the entire page →
From page 655... ... APPENDIX C 655 BOX C-14 Centaur Orbiter and Lander Scientific Objectives as Studied Understand Early Solar System Compositional Reservoirs: Deter mine isotopic composition, large-scale mineralogical make-up, grain scale composition, and interior volatile composition Understand the Accretion and Dynamical Evolution of Primordial Icy Planetesimals: Determine impact history and relative ages, physi cal characteristics of the body, internal mass distribution, and magne tism present during formation and accretion Determine the Geological and Evolutionary Processes That Have Influenced Icy Planetesimals: Determine landforms and any evidence of changes over the mission; icy regolith characteristics, surface weathering, source and cause of activity (if present) , and characteristics of ring systems Investigate the Biologic Potential of Icy Planetesimals and Poten tial Brine Reservoirs: Determine the thermal history by looking for Deployed Orbiter/Lander alteration minerals; determine the composition, form, and distribution of organic material. Read the entire page →
From page 656... ... 656 ORIGINS, WORLDS, AND LIFE BOX C-15 Uranus Orbiter and Probe Scientific Objectives Origins: When and where did Uranus form in the protosolar nebula? Did Uranus and Neptune migrate or swap positions? Read the entire page →
From page 657... ... APPENDIX C 657 BOX C-16 Calypso: Ariel and KBO Flyby Scientific Objectives as Studied Explore the Uranus System and Its Impact-Generated Moons: (potential ocean worlds) Search for Ariel subsurface ocean and internal structure Characterize Ariel crater populations Uranian System Science: Uranus, rings, ring-moons, and satellites Study Large Kuiper Belt Objects (KBOs) Read the entire page →
From page 658... ... 658 ORIGINS, WORLDS, AND LIFE BOX C-17 Neptune Odyssey, Neptune–Triton Orbiter and Probe Scientific Objectives as Studied Origins: Understand Neptune's origin and how it evolved, placing it in context with other planetary types Particles and Fields: Study Neptune's aurora and magnetic field to understand processes critical to the Neptune system, including explor ing Triton's interactions and whether Triton contains a subsurface ocean by observing auroral activity and magnetic induction Ocean Worlds: Study Triton's surface, interior, atmosphere, and magnetic interaction with Neptune to determine if it is an ocean world, understand plume activity, and how Triton's ionosphere is coupled with Neptune's magnetosphere Comparative Planetology: Compare and contrast attributes of Triton with other Kuiper Belt objects for a better understanding of dwarf planets Satellite and Ring Systems: Understand Neptune's ring-moon system Key Features Key Challenges Orbiter (20-yr life) Availability of SLS Block 2 with Centaur upper stage Payload (14 instruments) Read the entire page →
From page 659... ... APPENDIX C 659 BOX C-18 Triton Ocean World Surveyor Scientific Objectives as Studied Determine whether Triton is an ocean world, ascertain its interior structure, and decide whether Triton's ice shell is in hydrostatic equi Deployed Orbiter PIMS and librium and de-coupled from the interior LORRI out of sight to le Characterize Triton's surface composition and geology, and look for changes, including plumes and their composition Determine the nature of the moon–magnetosphere interaction at Triton Determine the composition, density, temperature, pressure, and spatial/temporal variability of Triton's atmosphere Key Features Key Challenges Orbiter/Lander (20-yr life, 16-yr cruise, 4-yr orbital mission) Lifetime reliability and power issues for long mission duration Payload: (6 instruments) Read the entire page →
From page 660... ... 660 ORIGINS, WORLDS, AND LIFE REFERENCES NASA (National Aeronautics and Space Administration) Read the entire page →

From page 633...

... Appendix C Technical Risk and Cost Evaluation of Priority Missions BACKGROUND The survey's statement of task (see Preface and Appendix A) calls for "identifying, recommending, and ranking the highest priority research activities" in planetary science, astrobiology, and planetary defense.