Endogenic and Exogenic Contributions to Visible-Wavelength Spectra of Europa’S Trailing Hemisphere
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Mission to Jupiter
This book attempts to convey the creativity, Project A History of the Galileo Jupiter: To Mission The Galileo mission to Jupiter explored leadership, and vision that were necessary for the an exciting new frontier, had a major impact mission’s success. It is a book about dedicated people on planetary science, and provided invaluable and their scientific and engineering achievements. lessons for the design of spacecraft. This The Galileo mission faced many significant problems. mission amassed so many scientific firsts and Some of the most brilliant accomplishments and key discoveries that it can truly be called one of “work-arounds” of the Galileo staff occurred the most impressive feats of exploration of the precisely when these challenges arose. Throughout 20th century. In the words of John Casani, the the mission, engineers and scientists found ways to original project manager of the mission, “Galileo keep the spacecraft operational from a distance of was a way of demonstrating . just what U.S. nearly half a billion miles, enabling one of the most technology was capable of doing.” An engineer impressive voyages of scientific discovery. on the Galileo team expressed more personal * * * * * sentiments when she said, “I had never been a Michael Meltzer is an environmental part of something with such great scope . To scientist who has been writing about science know that the whole world was watching and and technology for nearly 30 years. His books hoping with us that this would work. We were and articles have investigated topics that include doing something for all mankind.” designing solar houses, preventing pollution in When Galileo lifted off from Kennedy electroplating shops, catching salmon with sonar and Space Center on 18 October 1989, it began an radar, and developing a sensor for examining Space interplanetary voyage that took it to Venus, to Michael Meltzer Michael Shuttle engines. -
EJSM-Laplace Why Are Ganymede and Europa Habitable Worlds ?
Exploring icy satellites for their Astrobiological potential from an astronomical point of view Athena Coustenis LESIA, Paris-Meudon Observatory France Galileo Cassini-Huygens Quelques points de considération Aspects astrobiologiques: chimie organique, eau liquide (en surface ou à l’intérieur), sources d’énergie (activité interne), stabilité Les satellites de glace avec organiques : Titan, Encelade, Triton. avec une activité évidente : Encelade, Triton, Io, (Titan?) avec de l’eau liquide à l’intérieur (à confirmer): Europe, Ganymède, Encelade, Titan A l’exception de Titan, les satellites de glace avec des océans subsurfaciques possibles (Europe, Ganymède, Callisto) ou une activité cryovolcanique évidente (Encelade, Triton) résident à l’intérieur des magnétosphères des planètes géantes, mais les deux derniers ne sont pas dans la partie avec l’irradiation surfacique extrême et destructive pour les organiques. Quel est le potentiel astrobiologique de chacun de ces satellites? Exploring the Habitability of Icy Worlds: The Europa Jupiter System Mission (JUICE) The EJSM Science Study Team 2009 All rights reserved. EJSM Theme: The Emergence of Habitable Worlds Around Gas Giants • Goal 1: Determine if the Jupiter system harbors habitable worlds • Goal 2: Characterize Jupiter system processes – Ocean characteristics (for Europa and Ganymede and perhaps other satellites) – Satellite system – Ice shells and subsurface water – Jupiter atmosphere – Deep internal structure, and (for – Magnetodisk/magnetosphere Ganymede) intrinsic magnetic field – Jovian system Interactions – External environments – Jovian system origin – Global surface compositions – Surface features and future landing sites Emphasis on icy moon habitability and Jupiter system processes 5 JGO Science: Overview • Key JGO science phases – Ganymede: Detailed orbital study . Elliptical orbit first, then circular orbit – Jupiter system: In-depth exploration . -
Arxiv:2003.06680V2 [Astro-Ph.EP] 1 Apr 2021 Ations in Tidal Forces Alone
Europa's Hemispheric Color Dichotomy as a Constraint on Non-Synchronous Rotation Ethan R. Burnett∗1 and Paul O. Hayne2,3 1Aerospace Engineering Sciences, University of Colorado Boulder 2Astrophysical and Planetary Sciences, University of Colorado Boulder 3Laboratory for Atmospheric and Space Physics, University of Colorado Boulder Europa's surface reflectance exhibits a pronounced hemispheric dichotomy, which is hypoth- esized to form due to enhanced irradiation of the trailing hemisphere by energetic particles entrained in the jovian magnetosphere. We propose that this pattern can only persist if the timescale for discoloration is much shorter than that of Europa's rotation relative to the syn- chronous state, and provide a means for constraining the rotation rate using the observed color pattern. By decomposing the longitudinal ultraviolet and visible color variations from Voyager data into sine and cosine terms, we find no detectable signature of non-synchronous rotation (NSR). This same conclusion is reached with two observational models of discoloration: one representing an actively discoloring surface, and the other assuming that the present-day exo- genic discoloration on the surface is in steady-state. Magnitudes of the expected signature are presented as functions of the age of the crater Pwyll, which is used to constrain the timescale of discoloration. Furthermore, we develop a physical model of discoloration to validate the ge- ometric models, producing consistent results. The failure to identify a signature of NSR using Europa's hemispheric color dichotomy magnifies the outstanding problem of the origin of the stress to explain Europa's pervasive tectonic features. 1 Introduction and Background The present-day icy surface of Europa is covered with large ridges and cracks, which are generally the result of tidal stresses during Europa's eccentric 3.55-day orbit about Jupiter. -
Uncorrected Proof
Planetary and Space Science xxx (xxxx) xxx-xxx Contents lists available at ScienceDirect Planetary and Space Science journal homepage: http://ees.elsevier.com Joint Europa Mission (JEM) a multi-scale study of Europa to characterize its habitability and search for extant life Michel Blanc a,∗, Nicolas André a, Olga Prieto-Ballesteros b, Javier Gomez-Elvira b, Geraint Jones c, Veerle Sterken d,e, William Desprats a,f, Leonid I. Gurvits g,p,ak, Krishan Khurana h, Aljona Blöcker i, Renaud Broquet j, Emma Bunce k, Cyril Cavel j, Gaël Choblet l, Geoffrey Colins m, Marcello Coradini n, John Cooper o, Dominic Dirkx p, Philippe Garnier a, David Gaudin f, Paul Hartogh q, Luciano Iess r, Adrian Jäggi d, Sascha Kempf s, Norbert Krupp q, Luisa Lara t, Jérémie LasuePROOFa, Valéry Lainey u, François Leblanc v, Jean-Pierre Lebreton w, Andrea Longobardo x, Ralph Lorenz y, Philippe Martins z, Zita Martins aa, Adam Masters ab,al, David Mimoun f, Ernesto Palumba x, Pascal Regnier j, Joachim Saur ac, Adriaan Schutte ad, Edward C. Sittler o, Tilman Spohn ae, Katrin Stephan ae, Károly Szegő af, Federico Tosi x, Steve Vance ag, Roland Wagner ae, Tim Van Hoolst ah, Martin Volwerk ai, Frances Westall aj a IRAP, France b INTA-CAB, Spain c MSSL/UCL, UK d University of Bern, Switzerland e ETH Zürich, Switzerland f ISAE, France g Joint Institute for VLBI ERIC, Dwingeloo, the Netherlands h UCLA, USA i Royal Institute of Technology KTH, Sweden j Airbus D&S, France k Univ. Leicester, UK l LPG, Univ. Nantes, France mWheaton College, USA n CSEO, USA o GSFC, USA p TU Delft, the Netherlands q MPS, Germany r Univ. -
Schmidt Et Al
Earth and Planetary Science Letters 384 (2013) 37–41 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Detectability of thermal signatures associated with active formation of ‘chaos terrain’ on Europa ∗ Oleg Abramov a, , Julie A. Rathbun b, Britney E. Schmidt c,JohnR.Spencerd a U.S. Geological Survey, Astrogeology Science Center, 2255 N. Gemini Dr., Flagstaff, AZ 86001, USA b Planetary Science Institute, 1700 E. Fort Lowell Rd., Suite 106, Tucson, AZ 85719-2395, USA c Georgia Institute of Technology, School of Earth and Atmospheric Sciences, 311 Ferst Dr., Atlanta, GA 30312, USA d Southwest Research Institute, 1050 Walnut St., Suite 300, Boulder, CO 80302, USA article info abstract Article history: A recent study by Schmidt et al. (2011) suggests that Thera Macula, one of the “chaos regions” on Europa, Received 21 February 2013 may be actively forming over a large liquid water lens. Such a process could conceivably produce a Received in revised form 12 September thermal anomaly detectable by a future Europa orbiter or flyby mission, allowing for a direct verification 2013 of this finding. Here, we present a set of models that quantitatively assess the surface and subsurface Accepted 20 September 2013 temperatures associated with an actively resurfacing chaos region using constraints from Thera Macula. Available online 26 October 2013 Editor: C. Sotin The results of this numerical study suggest that the surface temperature over an active chaos region can be as high as ∼200 K. However, low-resolution Galileo Photo-Polarimeter Radiometer (PPR) observations Keywords: indicate temperatures below 120 K over Thera Macula. -
Galileo Reveals Best-Yet Europa Close-Ups Stone Projects A
II Stone projects a prom1s1ng• • future for Lab By MARK WHALEN Vol. 28, No. 5 March 6, 1998 JPL's future has never been stronger and its Pasadena, California variety of challenges never broader, JPL Director Dr. Edward Stone told Laboratory staff last week in his annual State of the Laboratory address. The Laboratory's transition from an organi zation focused on one large, innovative mission Galileo reveals best-yet Europa close-ups a decade to one that delivers several smaller, innovative missions every year "has not been easy, and it won't be in the future," Stone acknowledged. "But if it were easy, we would n't be asked to do it. We are asked to do these things because they are hard. That's the reason the nation, and NASA, need a place like JPL. ''That's what attracts and keeps most of us here," he added. "Most of us can work elsewhere, and perhaps earn P49631 more doing so. What keeps us New images taken by JPL's The Conamara Chaos region on Europa, here is the chal with cliffs along the edges of high-standing Galileo spacecraft during its clos lenge and the ice plates, is shown in the above photo. For est-ever flyby of Jupiter's moon scale, the height of the cliffs and size of the opportunity to do what no one has done before Europa were unveiled March 2. indentations are comparable to the famous to search for life elsewhere." Europa holds great fascination cliff face of South Dakota's Mount To help achieve success in its series of pro for scientists because of the Rushmore. -
Rapid Single Image-Based DTM Estimation from Exomars TGO Cassis Images Using Generative Adversarial U-Nets
remote sensing Article Rapid Single Image-Based DTM Estimation from ExoMars TGO CaSSIS Images Using Generative Adversarial U-Nets Yu Tao 1,* , Siting Xiong 2, Susan J. Conway 3, Jan-Peter Muller 1 , Anthony Guimpier 3, Peter Fawdon 4, Nicolas Thomas 5 and Gabriele Cremonese 6 1 Mullard Space Science Laboratory, Imaging Group, Department of Space and Climate Physics, University College London, Holmbury St Mary, Surrey RH5 6NT, UK; [email protected] 2 College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China; [email protected] 3 Laboratoire de Planétologie et Géodynamique, CNRS, UMR 6112, Universités de Nantes, 44300 Nantes, France; [email protected] (S.J.C.); [email protected] (A.G.) 4 School of Physical Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, UK; [email protected] 5 Physikalisches Institut, Universität Bern, Sidlerstrasse 5, 3012 Bern, Switzerland; [email protected] 6 INAF, Osservatorio Astronomico di Padova, 35122 Padova, Italy; [email protected] * Correspondence: [email protected] Abstract: The lack of adequate stereo coverage and where available, lengthy processing time, various artefacts, and unsatisfactory quality and complexity of automating the selection of the best set of processing parameters, have long been big barriers for large-area planetary 3D mapping. In this paper, Citation: Tao, Y.; Xiong, S.; Conway, we propose a deep learning-based solution, called MADNet (Multi-scale generative Adversarial S.J.; Muller, J.-P.; Guimpier, A.; u-net with Dense convolutional and up-projection blocks), that avoids or resolves all of the above Fawdon, P.; Thomas, N.; Cremonese, G. -
Paleoflooding in the Solar System: Comparison Among Mechanisms For
Paleoflooding in the Solar System: comparison among mechanisms for flood generation on Earth, Mars, and Titan Devon Burr Earth and Planetary Sciences Department EPS 306 University of Tennessee Knoxville 1412 Circle Dr. Knoxville TN 39776-1410 USA [email protected] ABSTRACT Conditions allow surficial liquid flow on three bodies in the Solar System, Earth, Mars, and Titan. Evidence for surficial liquid flood flow has been observed on Earth and Mars. The mechanisms for generating flood flow vary according to the surficial conditions on each body. The most common flood-generating mechanism on Earth is wide-spread glaciation, which requires an atmospheric cycle of a volatile that can assume the solid phase. Volcanism is also a prevalent cause for terrestrial flooding, which other mechanisms producing smaller, though more frequent, floods. On Mars, the mechanism for flood generation has changed over the planet’s history. Surface storage of floodwater early in Mars’ history gave way to subsurface storage as Mars’ climate deteriorated. As on Earth, Mars’ flooding is an effect of the ability of the operative volatile to assume the solid phase, although on Mars, this has occurred in the subsurface. According to this paradigm, Titan conditions preclude extreme flooding because the operative volatile, which is methane, cannot assume the solid phase. Mechanisms that produce smaller but more frequent floods on Earth, namely extreme precipitation events, are likely the most important flood generators on Titan. 1. Introduction The historical flow of paleoflood science has risen and fallen largely in concert with prevailing scientific paradigms (Baker 1998). The paradigm in the 17 th century was catastrophism, the idea that geology is the product of sudden, short, violent events. -
Europa Deep Dive 2: Chemical Composition of Europa and State of Laboratory Data
Program Europa Deep Dive 2: Chemical Composition of Europa and State of Laboratory Data October 9–11, 2018 • Houston, Texas Institutional Support Lunar and Planetary Institute Universities Space Research Association Conveners Louise M. Prockter USRA/Lunar and Planetary Institute Jonathan Kay USRA/Lunar and Planetary Institute Science Organizing Committee Murthy S. Gudipati NASA Jet Propulsion Laboratory Reggie L. Hudson NASA Goddard Space Flight Center Lynnae C. Quick Smithsonian Institution/Air and Space Museum Abigal M. Rymer Johns Hopkins University/Applied Physics Laboratory Jason M. Soderblom Massachusetts Institute of Technology Lunar and Planetary Institute • 3600 Bay Area Boulevard • Houston TX 77058-1113 Abstracts for this workshop are available via the workshop website at https://www.hou.usra.edu/meetings/europadeepdive2018/ Abstracts can be cited as Author A. B. and Author C. D. (2018) Title of abstract. In Europa Deep Dive 2: Chemical Composition of Europa and State of Laboratory Data, Abstract #XXXX. LPI Contribution No. 2100, Lunar and Planetary Institute, Houston. Guide to Sessions Tuesday, October 9, 2018 8:30 a.m. Great Room Registration 9:30 a.m. Lecture Hall Terrestrial Based Observation 1:20 p.m. Lecture Hall Observations and Lab Work 5:00 p.m. Great Room Europa Deep Dive Poster Session Wednesday, October 10, 2018 9:00 a.m. Lecture Hall Effects of Radiation 12:40 p.m. Lecture Hall Lab Work and Modeling Thursday, October 11, 2018 9:00 a.m. Lecture Hall Lab Work and Analogues Program Tuesday, October 9, 2018 TERRESTRIAL BASED OBSERVATION 9:30 a.m. Lecture Hall Chair: Bryana Henderson 9:30 a.m. -
Active Formation of 'Chaos Terrain' Over Shallow Subsurface Water on Europa
LETTER doi:10.1038/nature10608 Active formation of ‘chaos terrain’ over shallow subsurface water on Europa B. E. Schmidt1, D. D. Blankenship1, G. W. Patterson2 & P. M. Schenk3 Europa, the innermost icy satellite of Jupiter, has a tortured young topography differs. Conamara Chaos is raised and contains raised surface1–4 and sustains a liquid water ocean1–6 below an ice shell of matrix ‘domes’. Thera Macula, however, is sunken below the sur- highly debated thickness1–5,7–10. Quasi-circular areas of ice disrup- rounding surface. These observations, informed by the environments tion called chaos terrains are unique to Europa, and both their on Earth described above, suggest a four-phase ‘lens-collapse model’ formation and the ice-shell thickness depend on Europa’s thermal for chaos terrain formation (Fig. 3). (1) Ascending thermal plumes of state1–5,7–17. No model so far has been able to explain why features relatively pure ice13 cross the eutectic point of overlying impure ice, such as Conamara Chaos stand above surrounding terrain and producing surface deflection in response to volume change associated contain matrix domes10,18. Melt-through of a thin (few-kilometre) with pressure melting of the ice (Fig. 3a). (2) Resulting hydraulic shell3,7,8 is thermodynamically improbable and cannot raise the gradients and driving forces produce a sealed, pressurized melt lens ice10,18. The buoyancy of material rising as either plumes of warm, (Fig. 3b). (3) Extension of the sinking brittle ice ‘lid’ over the lens pure ice called diapirs1,9–15 or convective cells16,17 in a thick (.10 ultimately generates deep fractures from below, allowing brine to both kilometres) shell is insufficient to produce the observed chaos be injected into and percolate through overlying ice, forming a fluidized heights, and no single plume can create matrix domes10,18. -
Intro to Solar System Jovian Planets and Moons 1 Jovian Planets
Jovian Planets and Moons Intro to Solar System Jovian Planets and Moons 1 Jovian Planets primitive, look much as they did at time of formation gas giants, completely different than the terrestrial planets Intro to Solar System Jovian Planets and Moons 2 Jupiter • largest most massive of all • size 140,00 km 11 Earths across • mass - 300 times Voyager Project, JPL, NASA that of Earth 3 • density 1300 kg/m Intro to Solar System Jovian Planets and Moons 3 Jupiter - Composition hydrogen, helium - liquid and gaseous gases that have been there since formation temperature: 130 K escape speed: 60 km/sec even hydrogen can’t get away! Intro to Solar System Jovian Planets and Moons 4 Jupiter - “Surface” there is NO surface !! convective flow in the atmosphere light regions: zones - tops of high pressure regions dark regions: belts - descending areas of low pressure convective flow tells us the interior is HOT! Intro to Solar System Jovian Planets and Moons 5 Jupiter - “Surface” rotation: 10 hours differential rotation => a fluid cloud speed: 43,00 km/hr Intro to Solar System Jovian Planets and Moons 6 Great Red Spot NASA permanent storm: observed in 1630 cooler than surrounding zone, is raised a few km above it rotates counterclockwise, 7 day period Intro to Solar System Jovian Planets and Moons 7 Jupiter - Atmosphere 82% Hydrogen 18% Helium ammonia ice crystals, liquid ammonia, water ice Galileo - Probe Entry Point 1000 km thick Intro to Solar System Jovian Planets and Moons 8 Jupiter - Internal Structure • low density and atmospheric composition -
Europa Quad Echo (EQE)
Europa Quad Echo (EQE) Sub-cryospheric investigation into the habitability of Europa Editors: - Kolja Hanke - Micha Nebel - Benjamin Heikki Redmond Roche December 2017 Contents Page Chapter 1 - Introduction To The Exploration Of Europa (Page 2) Chapter 2 - The Structure Of Europa (Page 3) Chapter 3 - The Required Parameters For Life (Page 5) Chapter 4 - The Zones Of Europa (Page 8) Chapter 5 - Indicators For Life (Page 10) 5.1 - Indicators of Astrobiology & Instrumentation (Page 10) 5.2 - Sensitivity of Instruments (Page 12) 5.3 - Amino-Acids as potential Indicator of Life (Page 13) 5.4 - Sterilisation (Page 15) Chapter 6 - Target Zones For Exploration (Page 17) 6.1 - Cryogenic Morphology Of Europa (Page 17) 6.2 - Target Zones Of Europa (Page 24) Chapter 7 - Discussion & Mission Options (Page 29) Chapter 8 - Reference List (Page 33) 1 December 2017 1. Introduction On the 8th of January 1610, Galileo Galilei pointed his telescope at Jupiter and made a ground- breaking discovery; changing humanity’s perspective of the Earth, the universe and its own place within it. He had discovered the four moons of Jupiter: Io, Ganymede, Callisto and Europa. In the following few centuries Europa, the smallest Galilean moon, was disregarded until exploration occurred in the 1970s with the Pioneer (10 & 11) and Voyager (1 & 2) flybys; and subsequently the Galileo Mission (1995-2003), which undertook detailed analyses of the Galilean network for the first time. The data collected by these missions revealed the Europan surface consists of water ice and seems to be very young, according to the small number of visible craters (Carlson et al., 2009).