DOCSLIB.ORG

COPYRIGHT NOTICE: Ralph Lorenz and Jacqueline Mitton: Titan Unveiled Is Published by Princeton University Press and Copyrighted, © 2008, by Princeton University Press

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
COPYRIGHT NOTICE: Ralph Lorenz and Jacqueline Mitton: Titan Unveiled Is Published by Princeton University Press and Copyrighted, © 2008, by Princeton University Press COPYRIGHT NOTICE: Ralph Lorenz and Jacqueline Mitton: Titan Unveiled is published by Princeton University Press and copyrighted, © 2008, by Princeton University Press. All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher, except for reading and browsing via the World Wide Web. Users are not permitted to mount this file on any network servers. Follow links for Class Use and other Permissions. For more information send email to: [email protected] 1. The Lure of Titan On July 1, 2004, the Cassini spacecraft arrived at Saturn after a journey from Earth lasting almost seven years. At 6.8 m in length, this monstrous robotic explorer was the largest western spacecraft ever to be dispatched on an interplanetary mission. Its battery of scientific instruments was designed to return images and data not only from the giant planet itself and its spectacular ring system, but also from members of Saturn’s family of over fifty moons. Foremost in interest among the diverse collection of icy worlds in orbit around Saturn was Titan, a body so special, so intri­ guing in its own right that Cassini carried with it a detachable package of instruments—named the Huygens probe—that would parachute through Titan’s atmosphere to observe its surface. By any reckoning, Titan is an unusual moon. It is 5,150 km across— nearly 50 percent bigger than our own Moon and 6 percent larger than Mercury. If it happened to orbit around the Sun, its size and character would easily make it as much a planet as Mercury, Venus, Earth, and Mars. But the landscape of this extraordinary world remained hidden to us throughout the first decades of the space age, partially because of Ti­ tan’s remote location and partially because it is swathed in a thick and visually impenetrable blanket of haze. Thanks to Cassini–Huygens and the technological advances that have vastly extended the reach of ground- based telescopes, the situation has now changed dramatically. Titan is undergoing an all-out scientific assault both by the most powerful tele­ scopes on Earth and from the cameras and radar aboard Cassini, the flag­ ship international space mission. This observational barrage, topped off by the Huygens probe’s daring drop down to the surface of Titan, is 1 2 CHAPTER 1 serving to unveil this enigmatic moon, revealing more of its intriguing features than we have ever seen before. THE IMPERATIVE TO EXPLORE When the two Voyager craft sped past Jupiter and Saturn between 1979 and 1981, they returned a wealth of new information about the two giant planets and their moons. But the images and data received from these missions were essentially snapshots—fleeting opportunistic glances at worlds demanding more serious and systematic attention. And as far as Titan was concerned, the results of these flybys were especially disappointing. Observing Titan was a high priority for the planners of the Voyager missions, and in November 1980, Voyager 1 passed Titan at a distance of 4,394 km. The encounter sent the spacecraft hurtling out of the plane of the solar system and prevented it from exploring any more moons or planets. However, curiosity about Titan was so great that the sacrifice was considered worth making. A principal reason for the great interest in Titan was the fact that it possesses a significant atmosphere. Astronomers had been aware of Ti­ tan’s atmosphere since 1944, when Gerard Kuiper announced that spec­ tra he had taken of Titan revealed the presence of methane gas. There­ fore, planetary scientists were not going to be surprised to find haze or clouds in the atmosphere, but at the very least, they hoped that parts of Titan’s surface would be visible when Voyager arrived. Unfortunately, those hopes were completely dashed. The whole of Titan proved to be shrouded from pole to pole in opaque orange haze. Voyager’s camera was sensitive only to visible light, and the spacecraft carried no instruments (such as an infrared camera or imaging radar) capable of probing below the haze. Voyager was able to return some important new data about the atmosphere but virtually nothing about the surface. The exploration of the Jupiter and Saturn systems continued to beckon, however, and the next logical step was to send orbiters to make close and detailed observations over a sustained period of time. Between the two of them, Jupiter and Saturn possess five of the seven largest moons of the solar system, and they both have far more known THE LURE OF TITAN 3 Figure 1.01. A Voyager-era montage of the Saturnian system. The sizes reflect the quality of imaging obtained on each object, rather than their actual size. Because little detail could be seen on Titan, it was perhaps unfairly portrayed small, at the upper right. (NASA) moons than any of the other major planets. With such a variety of plane­ tary bodies to observe from close quarters, not to mention Saturn’s iconic ring system, the urge to send orbiters was very compelling. As the nearer of the two, Jupiter was the first to be targeted. The Galileo spacecraft was launched on its six-year journey to Jupiter from the space shuttle in 1989. It operated successfully between 1995 and 2003 and was deliberately crashed into Jupiter at the end of its useful life. An orbiter for Saturn was scheduled to follow, and Titan was firmly in the sights of the Saturn mission planners. The Voyager experience gen­ erated an overwhelming incentive to design a mission to the Saturnian system capable of discovering what lay below Titan’s haze. Both the Na­ tional Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) were involved from early on with the conception and development of the mission; the idea from the beginning was to send an orbiter carrying a Titan probe. In what turned out to be a highly successful international collaboration, NASA provided the orbiter and ESA built the probe. The orbiter was named in honor of Giovanni Do­ 4 CHAPTER 1 menico Cassini, the French-Italian astronomer who discovered four of Saturn’s moons and the gap separating the two main rings. The probe was named after Christiaan Huygens, the Dutch astronomer who discov­ ered Titan. Cassini would be equipped with radar and infrared imaging capabilities for penetrating the haze; the independent probe was to para­ chute through the haze and radio back via Cassini the data collected by its instruments and camera. No mission as complex as Cassini–Huygens had ever before been un­ dertaken at such an immense distance from Earth. Even when Earth and Saturn are at their closest, the gulf between them is around 1.3 billion km. By the time Cassini was launched in 1997, Galileo had been per­ forming well at Jupiter for nearly two years, even though its main com­ munications dish had failed to unfurl correctly. But Saturn is roughly twice as far away as Jupiter. Light and radio signals take over an hour to make the one-way trip between Saturn and Earth, and even getting to Saturn at all would be less than straightforward. Cassini’s route was necessarily a convoluted one. The 5.5-ton spacecraft was launched by a powerful rocket but could not make the journey in a reasonable time without extra impetus. To get some additional kicks, the mission design relied on “gravity assist”—a maneuvering technique whereby spacecraft pick up speed from close encounters with planets. Before it could set out properly on the main leg of its journey to Saturn, Cassini made two loops around the inner solar system. To gather enough speed, it skimmed close to Venus on two separate passes and then swung by Earth. Some two years after it had been launched on October 15, 1997, Cassini was finally catapulted away from the vicinity of Earth and toward the outer solar system. It received a final boost at Jupiter, about the half­ way point. After being maneuvered into orbit around Saturn in July 2004, it embarked on a long series of loops, carefully planned to allow scrutiny of the planet, rings, and moons by its eleven instruments. If all went well, it would keep going for at least four more years. On December 25, 2004, Huygens parted company with Cassini and for twenty days followed an independent orbit that would bring it close to Titan. Then, on January 14, 2005, Huygens plunged into Titan’s atmo­ sphere. As it descended to the surface, it transmitted data for two hours and twenty-eight minutes and conducted operations for over three hours after landing, until its batteries were dead. Unfortunately, after one hour and twelve minutes, Cassini was below the horizon and could no longer THE LURE OF TITAN 5 relay the probe's data back to Earth; also, a technical glitch caused the loss of some information for one experiment (though it was largely recov­ ered by radio telescopes observing from Earth). Otherwise, to the delight of the triumphant science teams who anxiously monitored its progress, the probe worked almost entirely according to plan. Even before Huygens reached Titan, the Cassini orbiter had begun its own program of mapping and remote sensing that would take it on dozens of close encounters with Titan. All eleven of its instruments were to be used to collect data on Titan; the expected deluge of information began to arrive on cue in the second half of 2004.
Load more

Recommended publications
  • Titan and Enceladus $1 B Mission
    JPL D-37401 B January 30, 2007 Titan and Enceladus $1B Mission Feasibility Study Report Prepared for NASA’s Planetary Science Division Prepared By: Kim Reh Contributing Authors: John Elliott Tom Spilker Ed Jorgensen John Spencer (Southwest Research Institute) Ralph Lorenz (The Johns Hopkins University, Applied Physics Laboratory) KSC GSFC ARC Approved By: _________________________________ Kim Reh Dr. Ralph Lorenz Jet Propulsion Laboratory The Johns Hopkins University, Applied Study Manager Physics Laboratory Titan Science Lead _________________________________ Dr. John Spencer Southwest Research Institute Enceladus Science Lead Pre-decisional — For Planning and Discussion Purposes Only Titan and Enceladus Feasibility Study Report Table of Contents JPL D-37401 B The following members of an Expert Advisory and Review Board contributed to ensuring the consistency and quality of the study results through a comprehensive review and advisory process and concur with the results herein. Name Title/Organization Concurrence Chief Engineer/JPL Planetary Flight Projects Gentry Lee Office Duncan MacPherson JPL Review Fellow Glen Fountain NH Project Manager/JHU-APL John Niehoff Sr. Research Engineer/SAIC Bob Pappalardo Planetary Scientist/JPL Torrence Johnson Chief Scientist/JPL i Pre-decisional — For Planning and Discussion Purposes Only Titan and Enceladus Feasibility Study Report Table of Contents JPL D-37401 B This page intentionally left blank ii Pre-decisional — For Planning and Discussion Purposes Only Titan and Enceladus Feasibility Study Report Table of Contents JPL D-37401 B Table of Contents 1. EXECUTIVE SUMMARY.................................................................................................. 1-1 1.1 Study Objectives and Guidelines............................................................................ 1-1 1.2 Relation to Cassini-Huygens, New Horizons and Juno.......................................... 1-1 1.3 Technical Approach...............................................................................................
    [Show full text]
  • Ralph Lorenz Johns Hopkins – Applied Physics Lab
    Space phySicS Seminar Ralph Lorenz Johns Hopkins – Applied Physics Lab Sailing the Seas of Titan, Saturn's Earth-Like Moon Thursday, September 19, 2013 725 Commonwealth Ave. Refreshments at 3:30pm in CAS 500 Talk begins at 4:00pm in CAS 502 Abstract: Oceanography is no longer just an Earth Science. The ongoing NASA/ESA Cassini mission - still making exciting discoveries 10 years after its arrival in the rich Saturnian system - has found that three seas of liquid hydrocarbons adorn Saturn’s giant, frigid moon Titan. Titan was already exotic, having a thick, organic-rich atmosphere, and a diverse landscape with mountains, craters, river channels and vast fields of sand dunes, but these seas, and hundreds of lakes, present a new environment (low gravity, dense atmosphere, hydrocarbon liquid) in which to explore familiar and important physical processes such as air:sea heat and moisture exchange, wind- driven currents and waves, etc. Moreover, Titan’s seas (notably the two largest ones, Kraken Mare and Ligiea Mare, about 1000km and 400km across, respectively) offer an appealing and accessible target for future Titan exploration. This talk will review the latest findings from Cassini, and its prospects for new discoveries as we move towards Titan’s northern summer solstice in 2017, and the opportunities for future exploration which might include (as at Mars) orbiters and landers, but also vehicles that can exploit Titan’s environment such as balloons or airplanes. The most affordable near-term prospect for in-situ exploration is a capsule to float in the seas of Titan, where after splashdown it would drift in the winds to make a traverse across the sea, measuring the liquid composition and turbidity, studying conditions with cameras and meteorological instruments, and exploring the seabed with a depth sounder.
    [Show full text]
  • Titan a Moon with an Atmosphere
    TITAN A MOON WITH AN ATMOSPHERE Ashley Gilliam Earth 450 – Satellites of Jupiter and Saturn 4/29/13 SATURN HAS > 60 SATELLITES, WHY TITAN? Is the only satellite with a dense atmosphere Has a nitrogen-rich atmosphere resembles Earth’s Is the only world besides Earth with a liquid on its surface • Possible habitable world Based on its size… Titan " a planet in its o# $ght! R = 6371 km R = 2576 km R = 1737 km Ch$%iaan Huy&ns (1629-1695) DISCOVERY OF TITAN Around 1650, Huygens began building telescopes with his brother Constantijn On March 25, 1655 Huygens discovered Titan in an attempt to study Saturn’s rings Named the moon Saturni Luna (“Saturns Moon”) Not properly named until the mid-1800’s THE DISCOVERY OF TITAN’S ATMOSPHERE Not much more was learned about Titan until the early 20th century In 1903, Catalan astronomer José Comas Solà claimed to have observed limb darkening on Titan, which requires the presence of an atmosphere Gerard P. Kuiper (1905-1973) José Comas Solà (1868-1937) This was confirmed by Gerard Kuiper in 1944 Image Credit: Ralph Lorenz Voyager 1 Launched September 5, 1977 M"sions to Titan Pioneer 11 Launched April 6, 1973 Cassini-Huygens Images: NASA Launched October 15, 1997 Pioneer 11 Could not penetrate Titan’s Atmosphere! Image Credit: NASA Vo y a &r 1 Image Credit: NASA Vo y a &r 1 What did we learn about the Atmosphere? • Composition (N2, CH4, & H2) • Variation with latitude (homogeneously mixed) • Temperature profile Mesosphere • Pressure profile Stratosphere Troposphere Image Credit: Fulchignoni, et al., 2005 Image Credit: Conway et al.
    [Show full text]
  • DAVINCI: Deep Atmosphere Venus Investigation of Noble Gases, Chemistry, and Imaging Lori S
    DAVINCI: Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging Lori S. Glaze, James B. Garvin, Brent Robertson, Natasha M. Johnson, Michael J. Amato, Jessica Thompson, Colby Goodloe, Dave Everett and the DAVINCI Team NASA Goddard Space Flight Center, Code 690 8800 Greenbelt Road Greenbelt, MD 20771 301-614-6466 Lori.S.Glaze@ nasa.gov Abstract—DAVINCI is one of five Discovery-class missions questions as framed by the NRC Planetary Decadal Survey selected by NASA in October 2015 for Phase A studies. and VEXAG, without the need to repeat them in future New Launching in November 2021 and arriving at Venus in June of Frontiers or other Venus missions. 2023, DAVINCI would be the first U.S. entry probe to target Venus’ atmosphere in 45 years. DAVINCI is designed to study The three major DAVINCI science objectives are: the chemical and isotopic composition of a complete cross- section of Venus’ atmosphere at a level of detail that has not • Atmospheric origin and evolution: Understand the been possible on earlier missions and to image the surface at origin of the Venus atmosphere, how it has evolved, optical wavelengths and process-relevant scales. and how and why it is different from the atmospheres of Earth and Mars. TABLE OF CONTENTS • Atmospheric composition and surface interaction: Understand the history of water on Venus and the 1. INTRODUCTION ....................................................... 1 chemical processes at work in the lower atmosphere. 2. MISSION DESIGN ..................................................... 2 • Surface properties: Provide insights into tectonic, 3. PAYLOAD ................................................................. 2 volcanic, and weathering history of a typical tessera 4. SUMMARY ................................................................ 3 (highlands) terrain.
    [Show full text]
  • Scientific Observations with the Insight Solar Arrays: Dust, Clouds
    Scientific Observations With the InSight Solar Arrays: Dust, Clouds, and Eclipses on Mars Ralph Lorenz, Mark Lemmon, Justin Maki, Donald Banfield, Aymeric Spiga, Constantinos Charalambous, Elizabeth Barrett, Jennifer Herman, Brett White, Samuel Pasco, et al. To cite this version: Ralph Lorenz, Mark Lemmon, Justin Maki, Donald Banfield, Aymeric Spiga, et al.. Scientific Obser- vations With the InSight Solar Arrays: Dust, Clouds, and Eclipses on Mars. Earth and Space Science, American Geophysical Union/Wiley, 2020, 7 (5), 10.1029/2019EA000992. hal-02872154 HAL Id: hal-02872154 https://hal.sorbonne-universite.fr/hal-02872154 Submitted on 17 Jun 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives| 4.0 International License RESEARCH ARTICLE Scientific Observations With the InSight Solar Arrays: 10.1029/2019EA000992 Dust, Clouds, and Eclipses on Mars Special Section: Ralph D. Lorenz1 , Mark T. Lemmon2 , Justin Maki3 , Donald Banfield4 , InSight at Mars 5,6 7 3 3 Aymeric Spiga
    [Show full text]
  • EGU2018-19456-1, 2018 EGU General Assembly 2018 © Author(S) 2018
    Geophysical Research Abstracts Vol. 20, EGU2018-19456-1, 2018 EGU General Assembly 2018 © Author(s) 2018. CC Attribution 4.0 license. DRAGONFLY: in situ exploration of Titan’s meteorology Scot Rafkin (1), Ralph Lorenz (2), Elizabeth Turtle (2), Jason Barnes (3), Melissa Trainer (4), Alice Le Gall (5), Juan Lora (6), Chris McKay (7), Claire Newman (8), Mark Panning (9), Kristin Sotzen (2), Tetsuya Tokano (10), Colin Wilson (11), and the Dragonfly Team (1) Southwest Research Institute, Boulder, CO, USA, (2) Johns Hopkins Applied Physics Lab., Laurel, MD, USA, (3) Univ. Idaho, Moscow, ID, USA, (4) NASA Goddard Space Flight Center, Greenbelt, MD, USA, (5) Laboratoire Atmosphères, Milieux, Observations Spatiales, Guyancourt, France, (6) Univ. California, Los Angeles, CA, USA, (7) NASA Ames Research Center, Moffett Field, CA, USA, (8) Aeolis Research, Pasadena, CA, USA, (9) Jet Propulsion Laboratory California Institute of Technology, Pasadena, CA, USA, (10) Inst. fur Geophysik und Meteorologie, Univ. Koln, Koln, Germany, (11) Oxford Univ., Oxford, UK Dragonfly is a rotorcraft lander mission currently in a Phase A study under NASA’s New Frontiers Program that would take advantage of Titan’s dense atmosphere and low gravity to visit a number of surface locations to study how far chemistry can progress in environments that provide key ingredients for life. This mission architecture also permits and demands investigation of Titan’s atmosphere. First, Dragonfly is a lander that will spend >2 Earth years on Titan’s surface, long enough to observe many diurnal cycles, atmospheric waves, and perhaps even some seasonal change. The DraGMet (Dragonfly Geophysics and Meteorology) instrument package includes measurement of wind speed and direction (using sensors on each of the four rotor pylons, to assure that one or more sensors are upwind of and thus unperturbed by the vehicle), temperature and pressure, and methane humidity.
    [Show full text]
  • Titan Mare Explorer
    TiME Titan Mare Explorer Titan Mare Explorer (TiME): Proxemy Research First Exploration of an Extraterrestrial Sea Ellen Stofan TiME Science . Discovery of lakes and seas in Titan’s northern hemisphere confirmed the expectation that liquid hydrocarbons exist . Detection of the presence of ethane in Ontario Lacus near the South Pole (Brown et al., 2008) . 2 distinct types of features- lakes and seas, likely 10’s, >100 m deep . Post-Cassini, major questions will remain on the chemistry of sea liquids, their role in the overall methane cycle, the origin of sea basins, and seasonal processes and variability TiME Proprietary Information/Competition Sensitive Titan’s methane cycle • Titan’s methane cycle is analogous to Earth’s hydrologic cycle, with meteorological working fluid existing in condensed phase on surface and within crust, cycling through the surface atmosphere system and transporting mass and energy TiME Proprietary Information/Competition Sensitive TiME Science Target •Target: Ligeia Mare (78°N, 250°W) –One of the largest seas identified to date on Titan, surface area ~100,000 km2 –Backup target- Kraken Mare TiME Proprietary Information/Competition Sensitive TiME Science Team .PI: Ellen Stofan (Proxemy Research) .Co-Is: .Jonathan Lunine (Univ. of Az.) - Deputy PI .Ralph Lorenz (APL)- Project Scientist .Oded Aharonson (CalTech) .Beau Bierhaus (LM) .Ben Clark (SSI) .Caitlin Griffith (Univ. Arizona) .Ari-Matti Harri (FMI) .Erich Karkoschka (Univ. Arizona) .Randy Kirk (USGS) .Paul Mahaffy (Goddard) .Claire Newman (Ashima Research) .Mike Ravine (MSSS) .Melissa Trainer (GSFC) .Elizabeth Turtle (APL) .Hunter Waite (SWRI) .Margaret Yelland (Univ. Southampton) .John Zarnecki (Open University) TiME Proprietary Information/Competition Sensitive TiME Science Goals and Objectives .
    [Show full text]
  • Proquest Dissertations
    Characterizing transiting extrasolar giant planets: On companions, rings, and love handles Item Type text; Dissertation-Reproduction (electronic) Authors Barnes, Jason Wayne Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 01/10/2021 05:33:59 Link to Item http://hdl.handle.net/10150/290019 NOTE TO USERS This reproduction is the best copy available. UMI CHARACTERIZING TRANSITING EXTRASOLAR GIANT PLANETS: ON COMPANIONS, RINGS, AND LOVE HANDLES by Jason Wayne Barnes A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2 0 0 4 UMI Number: 3131584 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. UMI UMI Microform 3131584 Copyright 2004 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O.
    [Show full text]
  • Mars Insight Landing Press Kit
    Introduction National Aeronautics and Space Administration Mars InSight Landing Press Kit NOVEMBER 2018 www.nasa.gov 1 Table of Contents Introduction 3 Media Services 6 Quick Facts: Landing Facts 11 Quick Facts: Mars at a Glance 15 Mission: Overview 17 Mission: Spacecraft 29 Mission: Science 40 Mission: Landing Site 54 Program & Project Management 56 Appendix: Mars Cube One Tech Demo 58 Appendix: Gallery 62 Appendix: Science Objectives, Quantified 64 Appendix: Historical Mars Missions 65 Appendix: NASA’s Discovery Program 67 2 Introduction Mars InSight Landing Press Kit Introduction NASA’s next mission to Mars -- InSight -- is expected to land on the Red Planet on Nov. 26, 2018. InSight is a mission to Mars, but it is also more than a Mars mission. It will help scientists understand the formation and early evolution of all rocky planets, including Earth. In addition to InSight, a technology demonstration called Mars Cube One (MarCO) is flying separately to the Red Planet. It will test a new kind of data relay from another InSight will help us learn about the formation of Mars -- as well planet for the first time, though InSight’s success is not as all rocky planets. Credit: NASA/JPL-Caltech dependent on MarCO. Five Things to Know About Landing 1. Landing on Mars is difficult Only about 40 percent of the missions ever sent to Mars -- by any space agency -- have been successful. The U.S. is the only nation whose missions have survived a Mars landing. The thin atmosphere -- just 1 percent of Earth’s -- means that there’s little friction to slow down a spacecraft.
    [Show full text]
  • Planetary Penetrators: Their Origins, History and Future
    Author's personal copy Available online at www.sciencedirect.com Advances in Space Research 48 (2011) 403–431 www.elsevier.com/locate/asr Planetary penetrators: Their origins, history and future Ralph D. Lorenz ⇑ Johns Hopkins University, Applied Physics Laboratory, Laurel, MD 20723, USA Received 6 January 2011; received in revised form 19 March 2011; accepted 24 March 2011 Available online 30 March 2011 Abstract Penetrators, which emplace scientific instrumentation by high-speed impact into a planetary surface, have been advocated as an alter- native to soft-landers for some four decades. However, such vehicles have yet to fly successfully. This paper reviews in detail, the origins of penetrators in the military arena, and the various planetary penetrator mission concepts that have been proposed, built and flown. From the very limited data available, penetrator developments alone (without delivery to the planet) have required $30M: extensive analytical instrumentation may easily double this. Because the success of emplacement and operation depends inevitably on uncontrol- lable aspects of the target environment, unattractive failure probabilities for individual vehicles must be tolerated that are higher than the typical ‘3-sigma’ (99.5%) values typical for spacecraft. The two pathways to programmatic success, neither of which are likely in an aus- tere financial environment, are a lucky flight as a ‘piggyback’ mission or technology demonstration, or with a substantial and unprec- edented investment to launch a scientific (e.g. seismic) network mission with a large number of vehicles such that a number of terrain- induced failures can be tolerated. Ó 2011 COSPAR. Published by Elsevier Ltd. All rights reserved.
    [Show full text]
  • The Dragonfly Entry and Descent System IPPW 2019; Oxford, UK July 12, 2019
    The Dragonfly Entry and Descent System IPPW 2019; Oxford, UK July 12, 2019 Michael Wright (Dragonfly EDL Phase Lead) Jeff Herath, Helen Hwang, Jim Corliss, Aaron Brandis, Dave Buecher, Doug Adams, Ralph Lorenz New Frontiers 4 Site Visit | April 24, 2019 Proprietary Information/Competition Sensitive Michael Wright Introduction • As of June 27, we are going to Titan! - launch 2026, arrival 2034 • This talk will focus on the Entry and Descent system that will deliver the rotorcraft safely to its release point - see talks by Ken Hibbard (Tuesday) and Doug Adams (tomorrow morning) at this workshop for more details how we get from there to the ground! • Dragonfly EDL team combines expertise from NASA Ames/Langley and Lockheed Martin - Aeroshell hardware provider (LM) has extensive hardware expertise for all relevant EDL missions since Pathfinder • Titan EDL is well understood with robust performance margins across the subsystems - Extensive heritage exists that can be adapted to this mission application - Prior work for Huygens risk review (2004) and In-Space Propulsion Program lay the foundation for current EDL models - Titan EDL is more straightforward than Mars in several important ways InternationalNew Frontiers Planetary 4 Site Visit Probe | April Workshop 24, 2019 2019 Proprietary Information/Competition Sensitive Michael Wright 2 EDL Video Not included at the moment in the interest of file size for editing InternationalNew Frontiers Planetary 4 Site Visit Probe | April Workshop 24, 2019 2019 Proprietary Information/Competition Sensitive Michael Wright 3 EDL Concept of Operations • Entry Interface 1270 km - Spin stabilized to 2 RPM • Entry heat pulse: 250 sec. - Peak heat flux 250 W/cm2 margined • Drogue deploy E+6 min, ~Mach 1.5.
    [Show full text]
  • Silence on Shangri-La: Attenuation of Huygens Acoustic Signals Suggests Surface Volatiles
    This is a repository copy of Silence on Shangri-La: attenuation of Huygens acoustic signals suggests surface volatiles. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/80312/ Version: Accepted Version Article: Lorenz, RD, Leese, MR, Hathi, B et al. (6 more authors) (2014) Silence on Shangri-La: attenuation of Huygens acoustic signals suggests surface volatiles. Planetary and Space Science, 90. 72 - 80. ISSN 0032-0633 https://doi.org/10.1016/j.pss.2013.11.003 Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. [email protected] https://eprints.whiterose.ac.uk/ *(Revised) Manuscript, clean version Click here to download (Revised) Manuscript, clean version: HuygensSurfaceAcoustics_submit_Newabstract.docClick here to view linked References 1 1 2 3 4 5 6 7 8 9 10 Silence on Shangri-La : Detection of Titan Surface Volatiles by Acoustic 11 12 13 14 Absorption in Huygens Probe Measurements 15 16 17 18 19 20 21 22 23 24 25 Ralph D.
    [Show full text]