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National Aeronautics and Space Administration PLANETARY MISSION CONCEPT STUDY FOR THE 2023–2032 DECADAL SURVEY Mercury Lander Transformative science from the surface of the innermost planet August 08, 2020 Carolyn M. Ernst Principal Investigator Johns Hopkins University Applied Physics Laboratory [email protected] Sanae Kubota Design Study Lead Johns Hopkins University Applied Physics Laboratory [email protected] www.nasa.gov DATA RELEASE, DISTRIBUTION & COST INTERPRETATION STATEMENTS This document is intended to support the 2023–2032 Planetary Science and Astrobiology Decadal Survey. The data contained in this document may not be modified in any way. Cost estimates described or summarized in this document were generated as part of a preliminary concept study, are model-based, assume an APL in-house build, and do not constitute a commitment on the part of APL. Cost reserves for development and operations were included as prescribed by the NASA ground rules for the Planetary Mission Concept Studies program. Unadjusted estimate totals and cost reserve allocations would be revised as needed in future more-detailed studies as appropriate for the specific cost-risks for a given mission concept. MERCURY LANDER design study i ACKNOWLEDGEMENTS The Johns Hopkins Applied Physics Laboratory would like to thank all of the Mercury Lander team members and the NASA Planetary Mission Concept Study Program for supporting this study. Special thanks are due to Shoshana Weider, the NASA Point of Contact, for her contributions. ROLE NAME AFFILIATION Science Team Leadership Carolyn Ernst, Principal Investigator APL Nancy Chabot, Deputy Principal Investigator APL Rachel Klima, Project Scientist APL Geochemistry Kathleen Vander Kaaden, Group Lead Jacobs/NASA JSC Stephen Indyk Honeybee Robotics Patrick Peplowski APL Elizabeth Rampe NASA JSC Geophysics Steven A. Hauck, II, Group Lead Case Western Reserve University Sander Goossens University of Maryland, Baltimore County Catherine Johnson Planetary Science Institute Haje Korth APL Mercury Environment Ronald J. Vervack, Jr., Group Lead APL David Blewett APL Jim Raines University of Michigan Michelle Thompson Purdue University Geology Paul Byrne, Group Lead North Carolina State University Brett Denevi APL Noam Izenberg APL Lauren Jozwiak APL Programmatic Expertise Sebastien Besse, BepiColombo Liaison European Space Agency Ralph McNutt, Jr. APL Scott Murchie APL Engineering Team Avionics Norm Adams / Justin Kelman APL Cost Kathy Kha / Meagan Hahn APL Flight Software Chris Krupiarz APL G&C Gabe Rogers APL Mechanical Deva Ponnusamy / Derick Fuller APL Mission Design Justin Atchison / Jackson Shannon APL Mission Operations Don Mackey APL Landing Benjamin Villac APL Payload Rachel Klima / David Gibson APL Power Dan Gallagher / Doug Crowley APL Propulsion Stewart Bushman APL Management Dave Grant APL Systems Engineering Sanae Kubota / Gabe Rogers APL Telecomm Brian Bubnash APL Thermal Jack Ercol / Allan Holtzman APL Report Development Team Editing Marcie Steerman APL Graphics Gloria Crites / Christine Fink / Ben C. Smith / Matt Wallace APL MERCURY LANDER design study ii Engineering Gamma Ray Spectrometer (GRS) Geology Space Environment X-Ray Difractometer/ Geophysics X-Ray Fluorescence Spectrometer (XRD/XRF) Geochemistry Magnetometer (MAG) Accelerometer (MAC) Neutral Mass Spectrometer (NMS) Ion Mass Spectrometer (IMS) Energetic Particle Spectrometer (EPS) Dust Detector (DD) Regolith Imagers (FootCam) Mercury Panoramic Imager (StafCam) Descent Imagers (DescentCam) LIDAR Radio Science/ Lander Earth Communications PLANETARY MISSION CONCEPT STUDY FOR 2045 April 12 DUSK/LANDING THE 2023–2032 DECADAL SURVEY Week of: Overview: The only inner planet unexplored by a April 13 landed spacecraft, Mercury is an extreme end-member of planet formation with a unique mineralogy and April 20 interior structure. Mercury is also a natural laboratory to investigate fundamental planetary processes— including dynamo generation, crustal magnetization, April 27 particle–surface interactions, and exosphere production. May 04 Study Objective: Evaluate the feasibility of a landed mission to Mercury in the next decade to accomplish four fundamental science goals. May 11 Science Goal 1 (Geochemistry): Investigate the mineralogy and chemistry of Mercury’s surface. May 18 Science Goal 2 (Geophysics): Characterize Mercury’s interior structure and magnetic field. May 25 Science Goal 3 (Space Environment): Determine the active processes that produce Mercury’s exosphere and alter its regolith. June 01 NO EARTH COMMUNICATION NO EARTH Science Goal 4 (Geology): Characterize the landing site at a variety of scales and provide context for landed June 08 measurements. A Full Mercury Year On The Surface: June 15 The Mercury Lander touches down at dusk, permitting ~30 hours of sunlit measurements. Surface operations continue June 22 through the Mercury night (88 Earth days)—one full trip of Mercury about the Sun—providing unprecedented landed measurements of seasonal variations in Mercury’s space June 29 environment, a long baseline for geophysical investigations, and time for multiple geochemical sampling measurements. July 06 Sunrise brings an end to mission operations. July 11 DAWN/END OF MISSION MERCURY LANDER design study iii PLANETARY MISSION CONCEPT STUDY FOR THE 2023–2032 Mercury Lander DECADAL SURVEY The Mercury Lander flight system maximizes use Key Mission Characteristics of heritage components and leverages major NASA Launch March 2035, expendable Falcon Heavy investments (e.g. ion propulsion, NextGen RTG) to C3, Launch 14.7 km2/m2, 9410 kg (wet), 3680 kg (dry) enable a New-Frontiers-class landed Mass (MEV) mission to Mercury. Design Life 10.5 years Cruise stage: Solar Electric, Xenon Orbital stage: Bi-propellant, MMH and MON-3 Propulsion Descent stage: Solid Rocket Motor, TP-H-3340 Lander: Bi-propellant, MMH and MON-3 Cruise stage solar array • 9.3 kW BOL @ 0.99 AU for SEP • 1.4 kW BOL @ 0.99 AU for spacecraft Power Orbital stage solar array: 1.1 kW BOL @ 0.46 AU Orbital stage battery: 60 Ah BOL Lander battery: 4.5 Ah BOL Lander RTG: 16 GPHS NextGen RTG, 373W BOL Telecomm X-band and Ka-band, direct to Earth 10 Year solar electric propulsion cruise Jettison cruise stage Mercury orbit insertion 2.5 Months in 100 x 6000 km orbit Jettison orbital stage Initiate braking burn Jettison descent stage Hazard detection and avoidance Final landing Dust Detector Influx of micrometeoroids High-Gain Antenna and StafCam Neutral Mass Spectrometer Ka-band data return, radio science, and Composition and density of the panoramic landing site characterization near-surface neutral exosphere Magnetometer Magnetic field as a function of time FootCam Regolith characterization Ion Mass Spectrometer Fluxes of low-energy charged particles Gamma-Ray Energetic Particle Spectrometer Spectrometer Fluxes of high-energy charged particles (not shown) NextGen RTG Elemental composition Enables continuous DescentCam operations through Landing site the Mercury night characterization PI-Managed Cost PlanetVac sample transfer to X-Ray Accelerometer / Short Period Phase A-D w/o LV $1192M Difractometer / X-Ray Fluorescence Seismometer Phase E-F $316M Spectrometer Gravitational acceleration and Mineralogical composition seismic activity Total w/o LV $1508M MERCURY LANDER design study iv Planetary Science Decadal Survey Mercury Lander Mission Concept Design Study Final Report EXECUTIVE SUMMARY ................................................................................................................................. vi 1 SCIENTIFIC OBJECTIVES ......................................................................................................................... 1 1.1. Background & Science Goals ............................................................................................................. 1 1.2. Science Objectives & Science Traceability......................................................................................... 3 2 HIGH-LEVEL MISSION CONCEPT ............................................................................................................ 5 2.1. Overview ............................................................................................................................................ 5 2.2. Concept Maturity Level (CML) ........................................................................................................... 6 2.3. Technology Maturity ......................................................................................................................... 6 2.4. Key Trades ......................................................................................................................................... 6 3 TECHNICAL OVERVIEW .......................................................................................................................... 6 3.1. Instrument Payload Description ........................................................................................................ 6 3.2. Flight System ..................................................................................................................................... 9 3.3. Mission Design & Concept of Operations........................................................................................ 18 3.4. Risk List ............................................................................................................................................ 24 4 DEVELOPMENT SCHEDULE & SCHEDULE CONSTRAINTS ...................................................................
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