DOCSLIB.ORG

Triton Hopper: Exploring Neptune’S Captured Kuiper Belt Object

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Triton Hopper: Exploring Neptune’S Captured Kuiper Belt Object https://ntrs.nasa.gov/search.jsp?R=20180001294 2019-08-30T12:28:14+00:00Z NASA/TM—2018-219423 Triton Hopper: Exploring Neptune’s Captured Kuiper Belt Object Steve Oleson and Geoffrey Landis Glenn Research Center, Cleveland, Ohio January 2018 NASA STI Program . in Profile Since its founding, NASA has been dedicated • CONTRACTOR REPORT. Scientific and to the advancement of aeronautics and space science. technical findings by NASA-sponsored The NASA Scientific and Technical Information (STI) contractors and grantees. Program plays a key part in helping NASA maintain this important role. • CONFERENCE PUBLICATION. Collected papers from scientific and technical conferences, symposia, seminars, or other The NASA STI Program operates under the auspices meetings sponsored or co-sponsored by NASA. of the Agency Chief Information Officer. It collects, organizes, provides for archiving, and disseminates • SPECIAL PUBLICATION. Scientific, NASA’s STI. The NASA STI Program provides access technical, or historical information from to the NASA Technical Report Server—Registered NASA programs, projects, and missions, often (NTRS Reg) and NASA Technical Report Server— concerned with subjects having substantial Public (NTRS) thus providing one of the largest public interest. collections of aeronautical and space science STI in the world. Results are published in both non-NASA • TECHNICAL TRANSLATION. English- channels and by NASA in the NASA STI Report language translations of foreign scientific and Series, which includes the following report types: technical material pertinent to NASA’s mission. • TECHNICAL PUBLICATION. Reports of For more information about the NASA STI completed research or a major significant phase program, see the following: of research that present the results of NASA programs and include extensive data or theoretical • Access the NASA STI program home page at analysis. Includes compilations of significant http://www.sti.nasa.gov scientific and technical data and information deemed to be of continuing reference value. • E-mail your question to [email protected] NASA counter-part of peer-reviewed formal • Fax your question to the NASA STI professional papers, but has less stringent Information Desk at 757-864-6500 limitations on manuscript length and extent of graphic presentations. • Telephone the NASA STI Information Desk at 757-864-9658 • TECHNICAL MEMORANDUM. Scientific and technical findings that are preliminary or of • Write to: specialized interest, e.g., “quick-release” reports, NASA STI Program working papers, and bibliographies that contain Mail Stop 148 minimal annotation. Does not contain extensive NASA Langley Research Center analysis. Hampton, VA 23681-2199 NASA/TM—2018-219423 Triton Hopper: Exploring Neptune’s Captured Kuiper Belt Object Steve Oleson and Geoffrey Landis Glenn Research Center, Cleveland, Ohio National Aeronautics and Space Administration Glenn Research Center Cleveland, Ohio 44135 January 2018 Acknowledgments The authors wish to thank the NASA Advanced Innovative Concepts program for support and guidance during the Triton Hopper study. We also wish to recognize the COMPASS team for their innovations and completeness in performing this study. This report contains preliminary findings, subject to revision as analysis proceeds. Trade names and trademarks are used in this report for identification only. Their usage does not constitute an official endorsement, either expressed or implied, by the National Aeronautics and Space Administration. Level of Review: This material has been technically reviewed by technical management. Available from NASA STI Program National Technical Information Service Mail Stop 148 5285 Port Royal Road NASA Langley Research Center Springfield, VA 22161 Hampton, VA 23681-2199 703-605-6000 This report is available in electronic form at http://www.sti.nasa.gov/ and http://ntrs.nasa.gov/ Contents 1.0 Executive Summary .............................................................................................................................. 1 1.1 Science .......................................................................................................................................... 5 2.0 Study Background, Assumptions and Approach .................................................................................. 7 2.1 Introduction .................................................................................................................................. 7 2.2 Previous Studies ........................................................................................................................... 7 2.3 Triton Overview ........................................................................................................................... 8 2.4 Triton Operational Environment ................................................................................................... 8 2.5 Hopper Science ........................................................................................................................... 10 2.6 Study Purpose and Approach...................................................................................................... 11 2.7 Growth, Contingency, and Margin Policy .................................................................................. 11 2.7.1 Mass Growth ................................................................................................................... 14 2.7.2 Power Growth ................................................................................................................. 15 2.7.3 Redundancy Assumptions ............................................................................................... 15 2.8 Design Trades ............................................................................................................................. 15 3.0 Baseline Design .................................................................................................................................. 17 3.1 Concept of Operations (CONOPS) ............................................................................................. 17 3.2 Mission ....................................................................................................................................... 19 3.2.1 LV Ascent, Park Orbit and TTI ....................................................................................... 19 3.2.2 Earth to Triton Cruise ...................................................................................................... 19 3.2.3 Triton Entry, Descend, Landing and Operation .............................................................. 20 3.2.4 Operation of Triton Hopper............................................................................................. 21 3.3 System Level Summary .............................................................................................................. 24 3.4 Triton Entry System/Cruise Stage .............................................................................................. 24 3.5 Triton Concept Drawings and Descriptions ............................................................................... 26 4.0 Subsystem Breakdown ........................................................................................................................ 33 4.1 Science Payload and ISRU System ............................................................................................ 33 4.1.1 Science Requirements ..................................................................................................... 33 4.1.2 Science Instruments ........................................................................................................ 33 4.1.3 ISRU: Propellant Gathering Systems .............................................................................. 35 4.1.4 Science Payload and ISRU System MEL........................................................................ 37 4.2 Communications and Tracking ................................................................................................... 37 4.2.1 Communications Requirements ...................................................................................... 37 4.2.2 Communications Assumptions ........................................................................................ 38 4.2.3 Communications Design and MEL ................................................................................. 39 4.2.4 Communications System and Risk Analysis ................................................................... 41 4.3 Command and Data Handling (C&DH) System......................................................................... 41 4.3.1 C&DH Requirements ...................................................................................................... 41 4.3.2 C&DH Assumptions ....................................................................................................... 42 4.3.3 C&DH Design and MEL and Risks ................................................................................ 42 4.3.4 C&DH System Risk ........................................................................................................ 43 4.4 Guidance, Navigation, and Control (GN&C) ............................................................................. 43 4.4.1 GN&C Requirements ...................................................................................................... 43 4.4.2 GN&C Assumptions ......................................................................................................
Load more

Recommended publications
  • GAME of MOONS a TALE of ICE and FIRE 3 × 50 Min
    © NASA SCIENCE GAME OF MOONS A TALE OF ICE AND FIRE 3 × 50 min. Written and produced by Ivo Filatsch 4K, 5.1 and Stereo Executive Producer: Sabine Holzer Join us on a spectacular rollercoaster ride through our solar system! This three-part series explores alien worlds of extremes right in our celestial neighbourhood, each single one amazing, fascinating, and unique in its own way. veryone knows the moon — our Moon … case for Triton. It circles around Neptune in the It may come as a surprise, but there are opposite direction — in a retrograde orbit. more than 200 of these natural satellites But this brings a problem: the laws of physics orbiting other planets in the solar system! dictate that in this situation, Triton is being EAll these moons are incredibly different regarding slowed down all the while, this way getting ever their size, but also in terms of their environments. closer to Neptune. Studying these alien worlds in detail is important. Scientists have calculated that in about 100 Thanks to the insights scientists are getting million years from now, Triton will reach its Roche through observations, measurements, and radius. This is the zone where the gravitational conclusions, we all get a better understanding of forces of Neptune will become too strong to our world as a whole. withstand — and Triton will be ripped apart into pieces … And the better we understand our neighbour- hood, the better we get to know our home planet CHAPTER 2: LIFE … Our moon is much more than just a nice decora- tion in the night sky.
    [Show full text]
  • Pluto, Titan, and Triton: How Do Their Haze Properties Compare? B. J. Buratti1, J
    51st Lunar and Planetary Science Conference (2020) 1168.pdf Pluto, Titan, and Triton: How do their Haze Properties Compare? B. J. Buratti1, J. D. Hillier2, J. D. Hofgart- ner2, M. D. Hicks1, 1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109; bon- [email protected]; 2Grays Harbor College, Aberdeen, WA 98520. Introduction: The July 2015 encounter of the New Horizons spacecraft with Pluto brought a large Kuiper Belt Object into sharp focus for the first time [1]. In- struments on the spacecraft observed Pluto at solar phase angles not visible from the Earth, where the max- imum solar phase angle is about 2°. The large solar phase angles (>150°), are especially useful for charac- terizing the properties of Pluto’s haze. But key obser- vations were not made during the encounter because of the fast nature of the flyby. These included the small solar phase angles observable from Earth. Thus, the best data set is one consisting of both spacecraft and ground-based data. We have combined Earth-based observations, in- cluding those from the Palomar Adaptive Optics (AO) system, to construct a complete solar phase curve of Figure 1: Charon and Pluto from the Palomar Pluto. Using the classical radiative transfer model of adaptive optics system. Chandrasekhar’s “Planetary Problem” (2,3) we have fit Data from the spacecraft are summarized in Table physical parameters to the surface and haze of Pluto. 2. Comparison with the properties of Titan’s haze shows Table 1- New Horizons Data used in this Study. that both worlds are factories for producing reddish, organic rich molecules.
    [Show full text]
  • On Orbital Debris JEFF FOUST, COLLEGE PARK, Md
    NOVEMBER 24, 2014 SPOTLIGHT Clyde Space See page 12 www.spacenews.com VOLUME 25 ISSUE 46 $4.95 ($7.50 Non-U.S.) PROFILE/22> YVONNE PENDLETON DIRECTOR, SOLAR SYSTEM EXPLORATION RESEARCH VIRTUAL INSTITUTE INSIDE THIS ISSUE LAUNCH INDUSTRY Swift Development of Ariane 6 Urged Applauding the end of a French-German impasse over the Ariane 6 rocket, the European Satellite Operators Association said the vehicle needs to be in service as quickly as possible. See story, page 8 ATK Hints at Antares Engine Selection Alliant Techsystems Chief Executive Mark DeYoung said there are no near-term liquid- propulsion alternatives to Russian engines for U.S. rockets. See story, page 6 ESA PHOTO Virginia May Seek Federal Funds for Wallops > “We have found a compromise that is OK for both countries, for the other participating states and also for industry,” Brigitte Zypries (above), Germany’s Virginia’s two U.S. senators said they may seek federal funds to cover $20 million in repairs to the space minister, said of an agreement under which Germany and France will back the Ariane 6 rocket and scrap the Ariane 5 Midlife Evolution. Wallops Island launch pad damaged when Orbital Sciences’ Antares exploded. See story, page 6 MILITARY SPACE Protected Tactical Waveform Taking Shape German-French Compromise The U.S. Air Force is expected to demonstrate its protected tactical waveform in new modems and reworked terminals as early as 2018. See story, page 11 U.S. To Grant Indirect Access to Space Fence Paves Direct Path to Ariane 6 The Pentagon’s international space surveillance partners will have indirect access to data from the Air Force’s next-generation Space Fence tracking system.
    [Show full text]
  • Dwarf Planet Ceres
    Dwarf Planet Ceres drishtiias.com/printpdf/dwarf-planet-ceres Why in News As per the data collected by NASA’s Dawn spacecraft, dwarf planet Ceres reportedly has salty water underground. Dawn (2007-18) was a mission to the two most massive bodies in the main asteroid belt - Vesta and Ceres. Key Points 1/3 Latest Findings: The scientists have given Ceres the status of an “ocean world” as it has a big reservoir of salty water underneath its frigid surface. This has led to an increased interest of scientists that the dwarf planet was maybe habitable or has the potential to be. Ocean Worlds is a term for ‘Water in the Solar System and Beyond’. The salty water originated in a brine reservoir spread hundreds of miles and about 40 km beneath the surface of the Ceres. Further, there is an evidence that Ceres remains geologically active with cryovolcanism - volcanoes oozing icy material. Instead of molten rock, cryovolcanoes or salty-mud volcanoes release frigid, salty water sometimes mixed with mud. Subsurface Oceans on other Celestial Bodies: Jupiter’s moon Europa, Saturn’s moon Enceladus, Neptune’s moon Triton, and the dwarf planet Pluto. This provides scientists a means to understand the history of the solar system. Ceres: It is the largest object in the asteroid belt between Mars and Jupiter. It was the first member of the asteroid belt to be discovered when Giuseppe Piazzi spotted it in 1801. It is the only dwarf planet located in the inner solar system (includes planets Mercury, Venus, Earth and Mars). Scientists classified it as a dwarf planet in 2006.
    [Show full text]
  • MT Aerospace (Germany)
    https://ntrs.nasa.gov/search.jsp?R=20080014278 2019-08-30T04:19:50+00:00Z European Directions for Hypersonic Thermal Protection Systems and Hot Structures 31st Annual Conference on Composites Materials and Structures Daytona Beach, FL January 22, 2007 David E. Glass NASA Langley Research Center, Hampton, VA 23681 Approved for Public Release, Distribution Unlimited Agenda ♦ Background • Comments on prior ESA workshop • X-38 • Hopper ♦ Flight Vehicle Based Technology Development • IXV (ESA) • EXPERT (ESA) • USV (Italy) • SHEFEX (Germany) • SHyFE (UK) • LEA (France) • Foton (Russia) ♦ Non-Vehicle Specific Technology ♦ Concluding Remarks 2 European TPS and Hot Structures Research and Development ♦TPS and hot structures research and development critical for future space vehicles ♦Developing next generation TPS and hot structures technology (not Space Shuttle derived technology) ♦Long-term funding based on technology needs ♦Wide industry support and commitment to X-38 program ♦Test facilities developed for TPS and hot structures development • Thermal/structural test chamber • Arc-jet tunnels developed in recent years ♦Technology development has broad base • Fabrication • Testing • Large components • Fasteners • Bearings • Oxidation protection • Damage repair • Life cycle Wayne Sawyer comments from previous ESA TPS & Hot Structures Workshop 3 European TPS and Hot Structures Research and Development ♦ Proposing numerous experimental launch vehicles dedicated to or with TPS and hot structures research of prime consideration ♦ Committing significant
    [Show full text]
  • Mission Analysis and Preliminary Re-Entry Trajectory Design of the DLR Reusability Flight Experiment Refex
    8TH EUROPEAN CONFERENCE FOR AERONAUTICS AND SPACE SCIENCES (EUCASS) Mission Analysis and Preliminary Re-entry Trajectory Design of the DLR Reusability Flight Experiment ReFEx Sven Stappert*, Peter Rickmers*, Waldemar Bauer*, Martin Sippel* *German Aerospace Center (DLR), Institute of Space Systems, Robert-Hooke-Straße 7, 28359 Bremen [email protected], [email protected], [email protected], [email protected] Abstract Driven by the recently increased demand for investigating reusable launchers, the German Aerospace Center (DLR) is currently developing the Reusability Flight Experiment (ReFEx). The goal is to demonstrate the capability of performing an atmospheric re-entry, representative of a possible future winged reusable stage, and to develop and test key technologies for such reusable stages. The flight demonstrator ReFEx shall perform a controlled and autonomous re-entry from hypersonic velocity of approximately Mach 5 down to subsonic velocity after separation from the VSB-30 booster. The focus of this paper is the re-entry trajectory design for the ReFEx mission. Abbreviations AoA Angle of Attack AVS Avionics BC Ballistic Coefficient BoGC Begin of Guided Control CALLISTO Cooperative Action Leading to Launcher Innovation in Stage Tossback Operation DOF Degree of Freedom ELV Expendable Launch Vehicle EoE End Of Experiment GNC Guidance, Navigation and Control L/D Lift-to-Drag Ratio FPA Flight Path Angle LFBB Liquid Fly-Back Booster MECO Main Engine Cut-Off RCS Reaction Control System RLV Reusable Launch Vehicle TOSCA Trajectory Optimization and Simulation of Conventional and Advanced Spacecraft VTHL Vertical Takeoff, Horizontal Landing VTVL Vertical Takeoff, Vertical Landing 1. Introduction The recent successes of the emerging private space companies SpaceX and Blue Origin in landing, recovering and relaunching reusable first stages have demonstrated the possibility of building reliable and competitive reusable first stages.
    [Show full text]
  • The Solar System Cause Impact Craters
    ASTRONOMY 161 Introduction to Solar System Astronomy Class 12 Solar System Survey Monday, February 5 Key Concepts (1) The terrestrial planets are made primarily of rock and metal. (2) The Jovian planets are made primarily of hydrogen and helium. (3) Moons (a.k.a. satellites) orbit the planets; some moons are large. (4) Asteroids, meteoroids, comets, and Kuiper Belt objects orbit the Sun. (5) Collision between objects in the Solar System cause impact craters. Family portrait of the Solar System: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, (Eris, Ceres, Pluto): My Very Excellent Mother Just Served Us Nine (Extra Cheese Pizzas). The Solar System: List of Ingredients Ingredient Percent of total mass Sun 99.8% Jupiter 0.1% other planets 0.05% everything else 0.05% The Sun dominates the Solar System Jupiter dominates the planets Object Mass Object Mass 1) Sun 330,000 2) Jupiter 320 10) Ganymede 0.025 3) Saturn 95 11) Titan 0.023 4) Neptune 17 12) Callisto 0.018 5) Uranus 15 13) Io 0.015 6) Earth 1.0 14) Moon 0.012 7) Venus 0.82 15) Europa 0.008 8) Mars 0.11 16) Triton 0.004 9) Mercury 0.055 17) Pluto 0.002 A few words about the Sun. The Sun is a large sphere of gas (mostly H, He – hydrogen and helium). The Sun shines because it is hot (T = 5,800 K). The Sun remains hot because it is powered by fusion of hydrogen to helium (H-bomb). (1) The terrestrial planets are made primarily of rock and metal.
    [Show full text]
  • L. Summerera,∗, A. Galvezb, D. Izzoa, F
    64nd International Astronautical Congress, Beijing, China. Copyright 2013 by ESA. Published by the IAF, with permission and released to the IAF to publish in all forms. IAC-13.E.6.1.6 COMPETITIONS, GAMES AND PRIZES - MEANS FOR ADVANCED SPACE RESEARCH? L. Summerera,∗, A. Galvezb, D. Izzoa, F. Salzgeberc, A. de Clercqc, P. Manesc aESA Advanced Concepts Team, Keplerlaan 1, 2201 Noordwijk, The Netherlands bESA General Studies Programme, rue Mario Nikis, 75015 Paris, France cESA Technology Transfer Programme, Keplerlaan 1, 2201 Noordwijk, The Netherlands Abstract The traditional main mechanisms to advance science and technology in the space sector have recently been complemented by the use of competitions, prizes and games. Historically competitions and ex-ante prizes have played an important role among the tools of governments to stimulate innovation and advance science and technologies. Triggered by the success of the Ansari X-Prize in late 1990s / early 2000, these mechanisms have steadily gained grounds and supporters, also among governments. Scholarly literature on the effectiveness, advantages and disadvantages of these methods is emerging but still scarce. Most of the available scholarly literature assesses their impact based on US case studies and examples. The present paper provides a first analysis of these mechanisms and tools within the European Space Agency (ESA), based on three different areas: scientific research within its Advanced Concepts Team, business and innovation oriented competitions and prizes within the technology transfer programme and system level studies within the General Studies Programme. The ESA Advanced Concepts Team has experimented and used new ways of engaging with the larger scientific community via the use of scientific competitions, online games and scientific crowdsourcing experiments.
    [Show full text]
  • Jacques Tiziou Space Collection
    Jacques Tiziou Space Collection Isaac Middleton and Melissa A. N. Keiser 2019 National Air and Space Museum Archives 14390 Air & Space Museum Parkway Chantilly, VA 20151 [email protected] https://airandspace.si.edu/archives Table of Contents Collection Overview ........................................................................................................ 1 Administrative Information .............................................................................................. 1 Biographical / Historical.................................................................................................... 1 Scope and Contents........................................................................................................ 2 Arrangement..................................................................................................................... 2 Names and Subjects ...................................................................................................... 2 Container Listing ............................................................................................................. 4 Series : Files, (bulk 1960-2011)............................................................................... 4 Series : Photography, (bulk 1960-2011)................................................................. 25 Jacques Tiziou Space Collection NASM.2018.0078 Collection Overview Repository: National Air and Space Museum Archives Title: Jacques Tiziou Space Collection Identifier: NASM.2018.0078 Date: (bulk 1960s through
    [Show full text]
  • 1 on the Origin of the Pluto System Robin M. Canup Southwest Research Institute Kaitlin M. Kratter University of Arizona Marc Ne
    On the Origin of the Pluto System Robin M. Canup Southwest Research Institute Kaitlin M. Kratter University of Arizona Marc Neveu NASA Goddard Space Flight Center / University of Maryland The goal of this chapter is to review hypotheses for the origin of the Pluto system in light of observational constraints that have been considerably refined over the 85-year interval between the discovery of Pluto and its exploration by spacecraft. We focus on the giant impact hypothesis currently understood as the likeliest origin for the Pluto-Charon binary, and devote particular attention to new models of planet formation and migration in the outer Solar System. We discuss the origins conundrum posed by the system’s four small moons. We also elaborate on implications of these scenarios for the dynamical environment of the early transneptunian disk, the likelihood of finding a Pluto collisional family, and the origin of other binary systems in the Kuiper belt. Finally, we highlight outstanding open issues regarding the origin of the Pluto system and suggest areas of future progress. 1. INTRODUCTION For six decades following its discovery, Pluto was the only known Sun-orbiting world in the dynamical vicinity of Neptune. An early origin concept postulated that Neptune originally had two large moons – Pluto and Neptune’s current moon, Triton – and that a dynamical event had both reversed the sense of Triton’s orbit relative to Neptune’s rotation and ejected Pluto onto its current heliocentric orbit (Lyttleton, 1936). This scenario remained in contention following the discovery of Charon, as it was then established that Pluto’s mass was similar to that of a large giant planet moon (Christy and Harrington, 1978).
    [Show full text]
  • Comparative Kbology: Using Surface Spectra of Triton
    COMPARATIVE KBOLOGY: USING SURFACE SPECTRA OF TRITON, PLUTO, AND CHARON TO INVESTIGATE ATMOSPHERIC, SURFACE, AND INTERIOR PROCESSES ON KUIPER BELT OBJECTS by BRYAN JASON HOLLER B.S., Astronomy (High Honors), University of Maryland, College Park, 2012 B.S., Physics, University of Maryland, College Park, 2012 M.S., Astronomy, University of Colorado, 2015 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirement for the degree of Doctor of Philosophy Department of Astrophysical and Planetary Sciences 2016 This thesis entitled: Comparative KBOlogy: Using spectra of Triton, Pluto, and Charon to investigate atmospheric, surface, and interior processes on KBOs written by Bryan Jason Holler has been approved for the Department of Astrophysical and Planetary Sciences Dr. Leslie Young Dr. Fran Bagenal Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. ii ABSTRACT Holler, Bryan Jason (Ph.D., Astrophysical and Planetary Sciences) Comparative KBOlogy: Using spectra of Triton, Pluto, and Charon to investigate atmospheric, surface, and interior processes on KBOs Thesis directed by Dr. Leslie Young This thesis presents analyses of the surface compositions of the icy outer Solar System objects Triton, Pluto, and Charon. Pluto and its satellite Charon are Kuiper Belt Objects (KBOs) while Triton, the largest of Neptune’s satellites, is a former member of the KBO population. Near-infrared spectra of Triton and Pluto were obtained over the previous 10+ years with the SpeX instrument at the IRTF and of Charon in Summer 2015 with the OSIRIS instrument at Keck.
    [Show full text]
  • Electric Propulsion: a Key Enabling Technology for Planetary Exploration*
    Electric Propulsion: A Key Enabling Technology for Planetary Exploration* A White Paper for the Planetary Science and Astrobiology Decadal Survey 2023-2032 Jay Polk, Jet Propulsion Laboratory, California Institute of Technology [email protected], 818-281-1094 George Soulas, NASA Glenn Research Center [email protected], 216-977-7419 Andy Hoskins, Aerojet Rocketdyne [email protected], 425-945-6362 *The information presented in this white paper about future mission concepts and power systems is pre- decisional and is provided for planning and discussion purpose only. A portion of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). 1 Abstract. Electric propulsion is now widely accepted by industry, with over 900 operational spacecraft using electric thrusters as of June 30, 2020. Electric propulsion provides dramatic reductions in propellant mass which can enable many demanding mission concepts to meet their scientific and operational goals. It has already proven to be a critical enabling technology on science missions such as Dawn, Hayabusa I and II, and BepiColombo and is the key to making missions in development like Psyche and a potential Mars Sample Return possible. These examples show that electric propulsion can enable the use of smaller launch vehicles, provide mass margins that make missions much more robust, yield much greater flexibility in launch dates, reduce the number of critical events, and, in some cases, reduce trip times by eliminating the need for gravity assists. Electric propulsion systems developed by industry for commercial spacecraft and NASA- developed technologies for higher power and specific impulse support current mission applications, but ensuring that electric propulsion can meet the demands of future missions requires continued investment by NASA.
    [Show full text]