DOCSLIB.ORG

Enceladus Explorer: Next Steps in the Development and Testing of a Steerable Subsurface Ice Probe for Autonomous Operation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Enceladus Explorer: Next Steps in the Development and Testing of a Steerable Subsurface Ice Probe for Autonomous Operation Enceladus and the Icy Moons of Saturn (2016) 3031.pdf ENCELADUS EXPLORER: NEXT STEPS IN THE DEVELOPMENT AND TESTING OF A STEERABLE SUBSURFACE ICE PROBE FOR AUTONOMOUS OPERATION. B. Dachwald1, J. Kowalski2, F. Baader1, C. Espe1, M. Feldmann1, G. Francke1, E. Plescher1, 1Faculty of Aerospace Engineering, FH Aachen University of Applied Sciences, Hohenstaufenallee 6, 52064 Aa- chen, Germany, [email protected], 2Aachen Institute for Advanced Study in Computational Engineering Sci- ence, RWTH Aachen University, Germany Introduction: Direct access to subsurface liquid flexibly organized initiative with sub-projects focused material for in-situ analysis at Enceladus' South Polar on key research and development areas. The sub- Terrain is very difficult and requires advanced access project at FH Aachen is called EnEx-nExT (Environ- technology with a high level of cleanliness, robustness, mental Experimental Testing). Since the EnEx- and autonomy. A new technological approach has been IceMole was quite large (15 x 15 x 200 cm) and heavy developed as part of the collaborative research project / (60 kg), a much smaller (8 x 8 x 40 cm) and light- initiative “Enceladus Explorer” (EnEx) [1]. Within weight (< 5 kg) probe is currently developed within EnEx, the required technology for a potential Encela- EnEx-nExT. In the next two years, this smaller probe dus lander mission [2] is developed, evaluated, and will be tested in a vacuum chamber under simulated tested, with a strong focus on a steerable subsurface ice space conditions (pressure < 6 mbar, temperature probe. The EnEx probe shall autonomously navigate < 100 K) to prove the applicability of combined drill- through the ice and find a location where a liquid water ing and melting probes under more Enceladus-like sample can be taken and analyzed in situ. EnEx is environmental conditions. More detailed information funded and managed by the DLR Space Administra- about these experiments will be given in a separate tion and comprises several German universities. conference contribution. Within the sub-project EnEx- The Enceladus Explorer Project (2012–2015): DiMIce (Directional Melting in Ice), the complex Several prototypes of a steerable subsurface ice probe, melting behavior of such probes is modeled and simu- called IceMole, were developed and tested at FH Aa- lated at RWTH Aachen University. Information about chen since 2009. The IceMole design is based on the these computational models will be given as part of a novel concept of combining melting and mechanical separate conference contribution. feed – using an ice screw at the tip of the melting head [3]. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully Figure 1: EnEx-IceMole (with hull removed) tested between 2010 and 2012 on glaciers in Switzer- land and Iceland. They demonstrated downward, hori- zontal and upward melting, as well as curve driving and dirt layer penetration. Within the EnEx project, a more advanced probe, called EnEx-IceMole (Fig. 1), was developed between 2012 and 2015. It provides concepts for obstacle avoidance, target detection, and navigation in ice. This probe was successfully tested on Canada Glacier (Fig. 2) and Taylor Glacier, Antarc- tica, in 2013 and 2014, respectively [1]. During the 2014 deployment, it was used in international collabo- ration with the US-American NSF-funded MIDGE (Minimally Invasive Direct Glacial Exploration) pro- Figure 2: EnEx-IceMole deployment during Antarctic ject for clean access into Blood Falls, a unique aquatic field test subsurface environment, with subsequent return of a Acknowledgements: The project is supported by clean subglacial brine sample to the surface. Since the Federal Ministry of Economics and Technology, Blood Falls is categorized as an ASPA (Antarctic Spe- Germany, on the basis of a decision by the German cially Protected Area), we had to pay particular atten- Bundestag (FKZ: 50NA 1503) tion to clean protocols for the sampling of subglacial References: [1] Kowalski J. et al. (2016), Cold materials for biogeochemical analysis. Reg. Sci. Technol., 123, 53-70. [2] Konstantinidis K. et The Enceladus Explorer Initiative (2015+): After al. (2015), Acta Astronaut., 106, 63–89. [3] Dachwald the successful Antarctic deployment of the EnEx- B. et al. (2014), Ann. Glaciol., 55(65), 14-22. IceMole, EnEx was continued in the form of a more .
Load more

Recommended publications
  • Comparative Saturn-Versus-Jupiter Tether Operation
    Journal of Geophysical Research: Space Physics Comparative Saturn-Versus-Jupiter Tether Operation J. R. Sanmartin1 ©, J. Pelaez1 ©, and I. Carrera-Calvo1 Abstract Saturn, Uranus, and Neptune, among the four Giant Outer planets, have magnetic field B about 20 times weaker than Jupiter. This could suggest, in principle, that planetary capture and operation using tethers, which involve B effects twice, might be much less effective at Saturn, in particular, than at Jupiter. It was recently found, however, that the very high Jovian B itself strongly limits conditions for tether use, maximum captured spacecraft-to-tether mass ratio only reaching to about 3.5. Further, it is here shown that planetary parameters and low magnetic field might make tether operation at Saturn more effective than at Jupiter. Operation analysis involves electron plasma density in a limited radial range, about 1-1.5 times Saturn radius, and is weakly requiring as regards density modeling. 1. Introduction All Giant Outer planets have magnetic field B and corotating plasma, allowing nonconventional exploration. Electrodynamic tethers, which are thermodynamic (dissipative) in character, can 1. provide propellantless drag both for deorbiting spacecraft in Low Earth Orbit at end of mission and for planetary spacecraft capture and operation down the gravitational well, and 2. generate accompanying, useful electrical power, or store it to later invert tether current (Sanmartin et al., 1993; Sanmartin & Estes, 1999). At Jupiter, tethers could be effective because its field B is high (Sanmartin et al., 2008). Tethers would allow a variety of science applications (Sanchez-Torres & Sanmartin, 2011). The Saturn field is 20 times smaller, however, and tether operation involves field B twice, which makes that thermodynamic character manifest: 1.
    [Show full text]
  • Monday, November 13, 2017 WHAT DOES IT MEAN to BE HABITABLE? 8:15 A.M. MHRGC Salons ABCD 8:15 A.M. Jang-Condell H. * Welcome C
    Monday, November 13, 2017 WHAT DOES IT MEAN TO BE HABITABLE? 8:15 a.m. MHRGC Salons ABCD 8:15 a.m. Jang-Condell H. * Welcome Chair: Stephen Kane 8:30 a.m. Forget F. * Turbet M. Selsis F. Leconte J. Definition and Characterization of the Habitable Zone [#4057] We review the concept of habitable zone (HZ), why it is useful, and how to characterize it. The HZ could be nicknamed the “Hunting Zone” because its primary objective is now to help astronomers plan observations. This has interesting consequences. 9:00 a.m. Rushby A. J. Johnson M. Mills B. J. W. Watson A. J. Claire M. W. Long Term Planetary Habitability and the Carbonate-Silicate Cycle [#4026] We develop a coupled carbonate-silicate and stellar evolution model to investigate the effect of planet size on the operation of the long-term carbon cycle, and determine that larger planets are generally warmer for a given incident flux. 9:20 a.m. Dong C. F. * Huang Z. G. Jin M. Lingam M. Ma Y. J. Toth G. van der Holst B. Airapetian V. Cohen O. Gombosi T. Are “Habitable” Exoplanets Really Habitable? A Perspective from Atmospheric Loss [#4021] We will discuss the impact of exoplanetary space weather on the climate and habitability, which offers fresh insights concerning the habitability of exoplanets, especially those orbiting M-dwarfs, such as Proxima b and the TRAPPIST-1 system. 9:40 a.m. Fisher T. M. * Walker S. I. Desch S. J. Hartnett H. E. Glaser S. Limitations of Primary Productivity on “Aqua Planets:” Implications for Detectability [#4109] While ocean-covered planets have been considered a strong candidate for the search for life, the lack of surface weathering may lead to phosphorus scarcity and low primary productivity, making aqua planet biospheres difficult to detect.
    [Show full text]
  • The Europa and Enceladus Explorer Mission Designs. K
    Workshop on the Habitability of Icy Worlds (2014) 4043.pdf TOWARDS AN ASTROBIOLOGICAL VISION FOR THE OUTER SOLAR SYSTEM: THE EUROPA AND ENCELADUS EXPLORER MISSION DESIGNS. K. Konstantinidis1, C. L. Flores Martinez2, M. Hildebrandt3, and R. Förstner1, 1Bundeswehr University Munich, Institute for Space Technology and Space Applications, Werner-Heisenberg-Weg 39, 85579 Neubiberg, Bavaria, Germany, e-mail:[email protected] 2University of Heidelberg, Centre for Organismal Studies, Im Neuenheimer Feld 234, 69120 Heidelberg, Baden- Wurttemberg, Germany, e-mail: [email protected], 3German Research Institute for Artificial Intelligence (DFKI), Robert-Hooke-Straße 5, 28359, Bremen, Germany, e-mail: [email protected] Introduction: The firmly astrobiologically in-situ analysis of ice and subglacial liquids. The EnEx oriented exploration of the Solar System promises to mission concept under development at the Institute for revolutionize our understanding of how and where life Space Technology and Space Applications (ISTA) of in the Universe can originate, evolve and develop. In the Bundeswehr University Munich is comprised of a case organisms, which arose independently from Lander carrying a nuclear reactor providing 5 kW of terrestrial life, can be discovered beyond Earth, general electrical power, and the IceMole, and an Orbiter with notions of evolutionary biology, planetary science and the main function to act as a communications relay even cosmology will undergo revision in light of more between the Lander and Earth. After launch, the widespread biological activity throughout the Cosmos. combined spacecraft uses the on-board nuclear reactor In more practical terms the great hypothesis of a living to power electric thrusters and eventually capture Universe can only be verified, or falsified, via around Enceladus.
    [Show full text]
  • Dienstag, 15. März 2016 Vorträge/Poster
    Dienstag, 15. März 2016 Vorträge/Poster 45 DIENSTAG, 15.03.2016 15.03.2016, DIENSTAG 09:30–09:45 3-B.003 6-B Geophysical Methods – Oral Session 2 – Seismik Seismotectonics of the Pamir and the 1911/2015 M7 Sarez earthquake doublet Schurr, B., Kulikova, G., Krüger, F., Metzger, S., Zhang, Y., Ratschbacher, L., Yuan, X. Dienstag, 15. März 2016 | 09:00–10:30 | Raum: HS1 Moderation: Stefanie Donner 09:45–10:00 3-B.004 Imaging the deep structure of the northeastern and eastern margins of the Tibet 09:00–09:15 6-B.001 plateau Data-driven near-surface velocity analysis Mechie, J., Qian, H., Karplus, M., Feng, M., Li, H., Zhao, W. Guntern, C., Schwarz, B., Gajewski, D. 10:00–10:15 3-B.005 09:15–09:30 6-B.002 Seismische Streuung und Dämpfung am Vulkan Ätna Wavefront-based joint passive source location and velocity inversion Zieger, T., Sens-Schönfelder, C., Ritter, J.R.R. Schwarz, B., Bauer, A., Gajewski, D. 10:15–10:30 3-B.006 09:30–09:45 6-B.003 1-D and 3-D velocity analysis of the West Bohemia seismic zone A new filter function for diffraction separation with finite-offset CRS Kieslich, A., Alexandrakis, C., Calò, M., Vavryčuk, V., Buske, S. Wissmath, S., Vanelle, C., Schwarz, B., Gajewski, D. 09:45–10:00 6-B.004 Improved stacking workflow for diffraction imaging Walda, J., Schwarz, B., Gajewski, D. 2-B Exploration and Monitoring – Oral Session 2 – Monitoring/Geothermal 10:00–10:15 6-B.005 Utilizing diffractions: wavefront-based tomography revisited Dienstag, 15.
    [Show full text]
  • Bare-Tether Missions Paradigm for Exploration of Oceanworlds in Plumes of Icy Moons Enceladus, Europa, and Triton
    Bare-Tether Missions Paradigm for Exploration of OceanWorlds in Plumes of Icy Moons Enceladus, Europa, and Triton Juan R. Sanmartin 34 + 910675922 Universidad Politécnica de Madrid / Emerito Real Academia de Ingeniería [email protected] I.- Introduction The case of Ice Giants, which only received flyby missions, is of particular interest as regards exploration. There are multiple issues of interest in exploring Uranus and Neptune as different from Gas Giants: Composition is definitely different; rocky mass-percent is much larger; both planetary dynamics and magnetic structures present striking differences (quite relevant for tether interaction); exoplanet statistics suggests Ice types are well more abundant than Gas types. This raises questions about exomoons and exomagnetics… As regards considering tethers for a Neptune mission, beyond just a flyby, there would seem to exist a basic problem with standard methods. The Introduction section of NASA’s “Ice Giants” Pre-Decadal Mission Study Report, JPL D-100520, June 2017 (529 pp), in Sec.2.3.3, recalls the multiple studies, over the last half-century, on mission design options for exploration of Uranus and Neptune, ranging from just chemical propulsion to electric propulsion, both with and without gravity assists, and a variety of mission architectural concepts. First, such faraway missions appear quite costly. In the Report the estimated cost of a Flagship Neptune mission was $1.972B, $300M less for Uranus, whereas total budget for both planets was $2B. Secondly, available solar power is practically nil in a large part of the trip, spacecraft capture by chemical propulsion leading to high wet-mass, with scientific load limited to a small mass fraction, and orbital maneuvers quite reduced after capture.
    [Show full text]
  • Enceladus -Home of Extraterrestrial Life? Pia Friend*, Alex Kyriacou
    Enceladus -home of extraterrestrial life? Pia Friend*, Alex Kyriacou Astroparticle School 2018 Obertrubach-Bärnfels October 3rd -11th 1 Just one of Saturn’s icy moons? Credit: John Spencer With a position at 10 AU, Enceladus is far outside the habitable zone! [email protected] Enceladus 09.10.2018 2 …but as we all know, aliens must exist.... Credit: John Spencer Credit: Image.google.de [email protected] Enceladus 09.10.2018 3 So, let’s have a closer look: §Diameter of about 500 km §Surface temperature of about -200 °C §Very high albedo -> Due to young icy surface -> Geologically active body §Moment of inertia = 0.335 (0.4 for homogenous rocks) -> Enceladus is a differentiated body Enhanced colour image from Cassini. Credit: NASA [email protected] Enceladus 09.10.2018 4 Differentiation of planetary bodies §Accretion of “random” material in young solar system §Heating after accretion due to decay of short-lived (now distinct) isotopes - e.g. 26Al -> Bodies large and old enough to inherited sufficient short-lived isotopes got melted and have separated Crust lighter Mantle elements heavier Core elements Undifferentiated body Redistribution of elements Differentiated body Increasing temperature [email protected] Enceladus 09.10.2018 5 Differentiation of planetary bodies Earth: bulk density of ~5.5 g/cm3 Enceladus: bulk density of ~1.6 g/cm3 Mantle: Crust: H O (liquid and solid) O, Si, Al, Ca, Na 2 Core: metals and Mantle: silicates Si, Fe, Mg Core: Fe, Ni No crust Credit: ubisafe.org Credit: hagablog.co.uk [email protected] Enceladus 09.10.2018 6 Cassini’s discoveries I 2005: south polar plume (cryovulcanism) on Enceladus discovered by distant high phase imaging -> Enceladus unite liquid water with thermal energy Enhanced pseudocolour image from Cassini.
    [Show full text]
  • J. R. Sanmartin, J. Pelaez, H. B. Garrett, & I. Carrera
    On Use of Electrodynamic Tethers for Saturn Missions II J. R. Sanmartin1 , J. Pelaez1, H. B. Garrett,2 & I. Carrera1 (1) E. T. S. I. A. E. , Universidad Politécnica de Madrid. (2) J. P. L./ California Institute of Technology. 1. Saturn versus Jupiter in Tether Operations 2. Can a tether at Saturn capture a S/C with mass ratio of 3? All Giant Planets have plasma & magnetic field B allowing non-conventional explorations: For aluminum, ≈ 0.0083 for Saturn and 2.11 for Jupiter. A gravity-assist from Jupiter in a Hohmann route to Saturn could shorten the trip and reduce v∞, increasing by a 4.8 factor. Electrodynamic tethers (thermodynamic in character) can a) provide propellant-less drag for planetary capture and operation down the gravitational well, 1) Averaging over angle between tether and Em in wd, arises from tether spin introduced for Jupiter to and b) generate accompanying power, or store it to later invert tether current limit tether bowing [2]. For the Saturn weak-field no spin is required, wd increasing by about 2. Tethers are effective at Jupiter because its field B is high, 2) Work wd involves length-averaged tether current Iav, normalized with the short-circuit value but the Saturn field is 20 times smaller and tether operation involves field B twice: iav (L/L*) ≡ Iav / σtEmwh Length L* gauges ohmic & 1. The S/C velocity v’ relative to the magnetized planetary plasma induces in it a motional electric OML-collection impedances: iav field Em = v’B, in the S/C reference frame (a XIX century, Faraday effect) 2.
    [Show full text]
  • Microbial Morphology and Motility As Biosignatures for Outer Planet Missions
    Microbial Morphology and Motility as Biosignatures for Outer Planet Missions The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Nadeau, Jay; Lindensmith, Chris; Deming, Jody W.; Fernandez, Vicente I. and Stocker, Roman. “Microbial Morphology and Motility as Biosignatures for Outer Planet Missions.” Astrobiology 16, no. 10 (October 2016): 755–774 ©2012 Mary Ann Liebert, Inc. publishers As Published http://dx.doi.org/10.1089/ast.2015.1376 Publisher Mary Ann Liebert, Inc. Version Final published version Citable link http://hdl.handle.net/1721.1/109941 Terms of Use Creative Commons Attribution 4.0 International License Detailed Terms http://creativecommons.org/licenses/by/4.0/ ASTROBIOLOGY Volume 16, Number 10, 2016 Research Article Mary Ann Liebert, Inc. DOI: 10.1089/ast.2015.1376 Microbial Morphology and Motility as Biosignatures for Outer Planet Missions Jay Nadeau,1 Chris Lindensmith,2 Jody W. Deming,3 Vicente I. Fernandez,4 and Roman Stocker4 Abstract Meaningful motion is an unambiguous biosignature, but because life in the Solar System is most likely to be microbial, the question is whether such motion may be detected effectively on the micrometer scale. Recent results on microbial motility in various Earth environments have provided insight into the physics and biology that determine whether and how microorganisms as small as bacteria and archaea swim, under which condi- tions, and at which speeds. These discoveries have not yet been reviewed in an astrobiological context. This paper discusses these findings in the context of Earth analog environments and environments expected to be encountered in the outer Solar System, particularly the jovian and saturnian moons.
    [Show full text]
  • Advances in the Search for Life Hearing Committee On
    ADVANCES IN THE SEARCH FOR LIFE HEARING BEFORE THE COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY HOUSE OF REPRESENTATIVES ONE HUNDRED FIFTEENTH CONGRESS FIRST SESSION APRIL 26, 2017 Serial No. 115–11 Printed for the use of the Committee on Science, Space, and Technology ( Available via the World Wide Web: http://science.house.gov U.S. GOVERNMENT PUBLISHING OFFICE 25–467PDF WASHINGTON : 2017 For sale by the Superintendent of Documents, U.S. Government Publishing Office Internet: bookstore.gpo.gov Phone: toll free (866) 512–1800; DC area (202) 512–1800 Fax: (202) 512–2104 Mail: Stop IDCC, Washington, DC 20402–0001 COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY HON. LAMAR S. SMITH, Texas, Chair FRANK D. LUCAS, Oklahoma EDDIE BERNICE JOHNSON, Texas DANA ROHRABACHER, California ZOE LOFGREN, California MO BROOKS, Alabama DANIEL LIPINSKI, Illinois RANDY HULTGREN, Illinois SUZANNE BONAMICI, Oregon BILL POSEY, Florida ALAN GRAYSON, Florida THOMAS MASSIE, Kentucky AMI BERA, California JIM BRIDENSTINE, Oklahoma ELIZABETH H. ESTY, Connecticut RANDY K. WEBER, Texas MARC A. VEASEY, Texas STEPHEN KNIGHT, California DONALD S. BEYER, JR., Virginia BRIAN BABIN, Texas JACKY ROSEN, Nevada BARBARA COMSTOCK, Virginia JERRY MCNERNEY, California GARY PALMER, Alabama ED PERLMUTTER, Colorado BARRY LOUDERMILK, Georgia PAUL TONKO, New York RALPH LEE ABRAHAM, Louisiana BILL FOSTER, Illinois DRAIN LAHOOD, Illinois MARK TAKANO, California DANIEL WEBSTER, Florida COLLEEN HANABUSA, Hawaii JIM BANKS, Indiana CHARLIE CRIST, Florida ANDY BIGGS, Arizona ROGER W. MARSHALL, Kansas NEAL P. DUNN, Florida CLAY HIGGINS, Louisiana (II) C O N T E N T S April 26, 2017 Page Witness List ............................................................................................................. 2 Hearing Charter ...................................................................................................... 3 Opening Statements Statement by Representative Lamar S.
    [Show full text]
  • Friday, July 29, 2016 ASTROBIOLOGY and the FUTURE 9:00 A.M
    Enceladus and the Icy Moons of Saturn (2016) sess501.pdf Friday, July 29, 2016 ASTROBIOLOGY AND THE FUTURE 9:00 a.m. Boulderado Ballroom Chairs: Christopher Glein Amanda Stockton 9:00 a.m. McKay C. * Astrobiology of Enceladus 9:20 a.m. Duca Z. Tan G. Cantrell T. Van Enige M. Dorn M. Cato M. Putman P. Kim J. Mathies R. A. Stockton A. * Development of an Extraterrestrial Organic Analyzer (EOA) for Highly Sensitive Organic Detection on a Kinetic Penetrator [#3087] We show the development of an EOA for future planetary impact penetrator missions. EOA can survive a 50,000 g impact, making it the only current optical instrument with this capability. 9:35 a.m. Fujishima K. * Dziomba S. Takahagi W. Shibuya T. Takano Y. Guerrouache M. Carbonnier B. Takai K. Rothschild L. Yano H. A Fly-Through Mission Strategy Targeting Peptide as a Signature of Chemical Evolution and Possible Life in Enceladus Plumes [#3085] We present a combination of two latest and unpublished experiments that enable us to realize in situ life signature detection and chemical evolution for deep habitats of the “Ocean World.”. 9:50 a.m. Kowalski J. * Schüller K. Zimmermann A. Towards Simulation-Based Mission Support for Subsurface Exploration of the Icy Moons [#3077] Advanced subsurface mission scenarios for the icy moons suggest to deploy a robotic probe. In our contribution, we will present an integrated computational model for a probe migrating through ice, as well as its ambient cryospheric state. 10:05 a.m. Break 10:20 a.m. Baader F. * Dachwald B. Espe C.
    [Show full text]
  • 65Th International Astronautical Congress 2014 (IAC 2014)
    65th International Astronautical Congress 2014 (IAC 2014) Our World Needs Space Toronto, Canada 29 September - 3 October 2014 Volume 1 of 14 ISBN: 978-1-63439-986-9 Printed from e-media with permission by: Curran Associates, Inc. 57 Morehouse Lane Red Hook, NY 12571 Some format issues inherent in the e-media version may also appear in this print version. Copyright© (2014) by the International Astronautical Federation All rights reserved. Printed by Curran Associates, Inc. (2015) For permission requests, please contact the International Astronautical Federation at the address below. International Astronautical Federation 94 bis, Avenue de Suffren 75015 PARIS - France Phone: +33 1 45 67 42 60 Fax: +33 1 42 73 21 20 [email protected] Additional copies of this publication are available from: Curran Associates, Inc. 57 Morehouse Lane Red Hook, NY 12571 USA Phone: 845-758-0400 Fax: 845-758-2634 Email: [email protected] Web: www.proceedings.com TABLE OF CONTENTS VOLUME 1 A1.IAA/IAF SPACE LIFE SCIENCES A1.1. BEHAVIOUR, PERFORMANCE AND PSYCHOSOCIAL ISSUES IN SPACE IAC-14.A1.1.1 CORRELATION OF ETHO-SOCIAL AND PSYCHO-SOCIAL DATA FROM "MARS-5OO" INTERPLANETARY SIMULATION .............................................................................................................................................................1 Carole Tafforin IAC-14.A1.1.2 PSYCHOSOCIAL INTERACTION DURING A 9O-DAY ISOLATION MISSION IN LUNAR PALACE 1...........................................................................................................................................................................................................3
    [Show full text]
  • Aas 08-235 Integration of Orbit Trajectories in The
    AAS 08-235 INTEGRATION OF ORBIT TRAJECTORIES IN THE PRESENCE OF MULTIPLE FULL GRAVITATIONAL FIELDS * Matthew M. Berry † Vincent T. Coppola In this paper we demonstrate the effect of including multiple full gravitational fields in numerical orbit propagation, compared to only including one gravitational field and modeling the other bodies as point masses. Several test cases are examined in the Earth-Moon and the Jovian and Saturn systems. The tests show the increased accuracy gained by modeling multiple gravity fields. The tests also show the effect of changing the reference frame of the integration on the integrated trajectory. INTRODUCTION High-fidelity orbit propagation and orbit determination require accurate force modeling. For some missions, particularly lunar and interplanetary missions, modeling third bodies as point masses may not be sufficient to meet accuracy requirements. Higher-order gravity field terms can be included; however, including these terms increases the runtime of the orbit propagation. A study showing the increase in accuracy that including multiple full gravitational fields provides is required so mission analysts can decide whether including multiple gravity fields is necessary to meet their accuracy requirements. In this paper, we present such studies, in the Earth-Moon system as well as in the Jovian and Saturnian systems. In the first study, orbits around Earth at various altitudes are considered. The orbits are propagated once with the Moon's gravity modeled as a point mass, and then propagated using a lunar gravity field that includes J2 and higher terms. The ephemeris from the different propagations is compared to show the effect that the lunar gravity field has on the final position.
    [Show full text]