DOCSLIB.ORG

Planetary Geology in the Outer Solar System: the Search for Materials and the Research of Astrobiology Anezina Solomonidou Caltech – NASA/JPL Giant Planet Systems 1

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Planetary Geology in the Outer Solar System: the Search for Materials and the Research of Astrobiology Anezina Solomonidou Caltech – NASA/JPL Giant Planet Systems 1 Planetary Geology in the outer solar system: the search for materials and the research of astrobiology Anezina Solomonidou Caltech – NASA/JPL Giant Planet Systems 1. Why is Ganymede an habitable world Habitability in our Solar System: Extension of the zone *Water Surface habitats Deep habitats *Stable environment *Organics *Energy Deep habitats The habitable zone is not restricted to the Earth’s orbit… ESA’s Cosmic Vision 2015-2025: Ocean Worlds Planets and Life The NASA ‘Explore in situ the surface and Roadmap to subsurface of solid bodies in the Ocean Worlds Solar System most likely to host or have hosted life’ NASA (OPAG/ROW): ‘identify ocean worlds, characterize their oceans, evaluate their habitability, search for life, and ultimately understand any life we find.’ Dragonfly - NASA …vast oceans beneath thick ice crusts 4 Hendrix et al. 2019 Why does this matter? Geology - Habitability Understand the geology Unveil the connection between interior-surface-atmosphere Full interpretation Full interpretation of of composition composition Detection of cryovolcanism and internal activity ESA/ATG Medialab 5 Coustenis, Raulin, Bampasidis, Solomonidou (2012). Springer Solomonidou et al. (2011). J of Cos., Vol. 13, pp. 4191-4211 A. Karagiotas/NAI/JPL Titan Icy moons: The Dragonfly mission Titan Dragonfly: a rotocraft mission to Titan Mission type: Astrobiology Launch: 2027 Landing: 2036 7 CASSINI (2004-2017) HUYGENS (2005) A SPACECRAFT WITH 'HUMAN ABILITIES’ 12 instruments on Cassini 6 instruments on Huygens Huygens (01/2005): The descend and landing of Huygens 110-0 km 3d Parachute (2h13min) 156 km 1st Parachute (2 sec) 155-110 km 2nd Parachute (15 min) PHOEBE IAPETUS HYPERION Atlas Daphnis Pan Pandora Buratti et al., Science 2019 CASSINI (2004 - 2017): Highlights Titan and the Cassini mission Atmosphere: • N2 (Voyager, 1980) (98.4%)+CH4 (Kuiper, 1944) (1.5%)+H2 • Hydrocarbons, nitriles and oxygen compounds (traces) • Intense ionospheric chemistry in the upper levels (INMS) Surface: • Complex surface with multivariable geological expressions • Surface – atmosphere interaction • Active methane cycle Cassini 1979 1980 1981 2004-2017 Huygens 2005 15 Surface units Mountains Dunes Volcanoes? Drainage networks Lakes Jaumann et al. 2009; Lopes & Solomonidou, 2014 Lacustrine Lakes and Seas The mystery of Titan The methane cycle and the interior CH photolysis = Ethane + organics Process: Irreversible 4 like Earth’s hydrological cycle Various complex hydrocarbons, which form Titan’s haze layer Methane on Titan plays the role of water on Earth Mystery of the surface: what is the composition? Methane replenishment: where is the reservoir? Liquid hydrocarbon reservoir? Cryovolcanism? Tobie et al. 2005 18 Raulin, 2008 Titan: Surface – Subsurface – Habitability Habitability of Hydrocarbon Worlds: Titan and Beyond The single compelling question for this research is: What habitable environments exist on Titan and what resulting potential biosignatures should we look for? How are molecules transported across the surface and deposited/modified? How would we detect biosignatures that reach the surface and atmosphere? Titan’s surface from 3 Cassini instruments ✓Surface can only be imaged with IR and radar ✓We used a multi-swath mosaic from Cassini’s RADAR as a basemap ✓Synthetic Aperture Radar (SAR) gives best resolution of 300 meters per pixel ✓SAR swaths provide 65% coverage of the moon RADAR: RADAR: Radiometry SAR mode mode ISS SARTopo VIMS 20 Geomorphological types SAR Malaska et al., Lopes et al. 2016, Solomonidou et al. 2018 Undifferentiated Plains Streak-like Plains Variable Plains Scalloped Plains Hummocky Labyrinth Dunes Alluvial fans Maculae Radebaugh et al. 2016 Impact craters EvaporitesEvaporites Cryovolcanics Solomonidou et al. 2016 21 Barnes et al. 2013 Lopes et al. 2013 The 1st global geomorphological map of Titan 2400 km Titan is dominated by plain (65%) and dune fields (17%) (Lopes et al., 2020, Nature Geosciences) The mystery of Titan Map to it! (or finalizing the Titan Global map) 23 The VIMS data How to extract meaningful surface info from VIMS ‘Methane windows’ centered at 0.93, 1.08, 1.27, Titan spectrum 1.59, 2.03, 2.69-2.79 and 5.00 μm from VIMS However The haze extinction in the near-IR decreases with w/v, and methane absorption is not marginal Extracting information on the lower atmosphere and the surface from near-IR spectra requires a good understanding of the methane and haze contributions to the opacity. Our approach 1. Study Titan’s surface with specific tools 2. Use of theoretical and experimental data in a modular Radiative Transfer model Results Haze effect + Surface albedo 24 Surface albedo retrieval from VIMS A Radiative transfer code (RT) for Titan Code Plane-parallel (1D) Temperature profile HASI (Fulchignoni et al. 2005) CH4 mixing ratio GCMS (Neimann et al. 2010) Haze parameters DISR (Tomasko et al. 2008, de Bergh et al. 2011) 12 13 12 Atmospheric gases CH4, CH4, CH3D, CO, and collisions N2-N2 & N2-H2 (de Kok et al. 2007; Lafferty et al. 1996, McKellar et al. 1989) CH4 NEW UPDATED absorption (Boudon et al., 2006; Campargue et al. 2012, 2015 & Rey et al., 2017, HITRAN, coefficients GEISA, etc) Surface component candidates ices and tholins (Bernard et al. 2006; Coll et al. 2006; Brassie et al. 2015; B. Schmitt & S. Philippe private communications) ✓Test simulations with various haze opacities ✓Correlation between simulations and data ✓Best fit between VIMS and simulation Solomonidou et al. 2014, JGR 25 Hirtzig et al. 2013, Icarus; Solomonidou et al. 2014, JGR; Solomonidou et al. 2016, 2018 ,2019 Icarus 2020 A&A; Lopes et al. 2016, Icarus; Bonnefoy et al. 2016, Icarus Candidate materials for the surface of Titan New library of ices Work from B. Schmitt, S. Philippe & P. Coll GhoSST database H2O with a series of 15 grains sizes: 10, 20, 30, 40, 50, 75, 100, 150, 200, 250, 300, 400, 500, 750, and 1000 µm. We try to fit the albedos with the most adequate selection among 4 constituents x various grain sizes= When the best fit is obtained we identify the major constituent The solution is not unique but we can retrieve the most probable major constituents current work includes CH4, C2H2, C2H4, C2H6, C2H8, CO2, NH3, H2O, HC3N 26 4 projects on Titan’s key areas Solomonidou et al. (2014, 2016, 2018, 2020) 9 distinct geomorphological units +HLS Significant differences in albedo among various areas / 3 distinct albedo groups Project 2: Retrieval of pure surface albedo: Surface processing and weathering The fact that the spectral behavior is different for each of these areas, is indicative of diverse chemical compositions and origins. The wind transfers dune material to equatorial plains Lopes et al. Icarus, 2016 Solomonidou et al. JGR, 2018 75-120% haze contribution Solomonidou et al. JGR, 2018 wrt DISR Funded by NASA CDAP Project 2: Major constituent on various geomorphological types ✓ Very good correlation in the classification between SAR and VIMS ✓ 3 main types of surface albedo – 3 main types of major constituents: water ice: at latitudes higher than 30ºN and 30ºS tholin-like material, and an unknown very dark material: at equator ✓ Titan’s surface composition has a significant latitudinal dependence Project 3: Retrieval of pure surface albedo = Surface processing and interior The albedo differences and similarities among the various geomorphological units give insights on the geological processes affecting Titan’s surface and, by implication, its interior. Global amplitude pattern of maximum diurnal tidal stresses, Strongest cryovolcanic 휎tidē , overlaid onto an ISS map of candidate (Lopes et al. 2013) Possible cryovolcanic candidate Titan’s surface (Sohl et al. 2014). (Solomonidou et al. 2014) Reported temporal spectral changes (Nelson et al. 2009) Solomonidou et al. JGR, 2016 Funded by CDAP Surface changes on Titan Tui Regio through time 2005-2009 / Sotra Patera 2005-2006 Haze evolution Haze evolution Haze evolution Haze evolution 50% 50% factor of 2 factor of 2 20-50% decrease in surface albedo Increase in albedo up to a factor of 2 at all wavelengths at all wavelengths Tui Regio is getting darker Sotra Patera is getting brighter Solomonidou et al. 2016, Icarus Project 3: Spectral & emissivity of raised lake ramparts Solomonidou et al. 2019, Icarus Funded by CDAP & NAI Lakes with ramparts seem to be the youngest feature on Titan Project 4: The chemical composition of impact craters (Solomonidou et al. 2020, A&A) Titan, like Earth, has the limited number Why are they important? of impact craters Rare opportunity to understand the unlike the heavily cratered surfaces of the subsurface composition of Titan other Saturnian satellites Dragonfly’s landing site: the Selk crater So… what we know so far • Dunes are the youngest feature on Titan, along with lakes • Plains are the next youngest, act as a fill unit • Mountains are likely the oldest unit • Mapping results (1 meter of crust) suggest the equatorial and mid-latitudes of Titan are dominated by organic materials being deposited and emplaced by aeolian activity VIMS results (few μm of the surface) show a latitudinal dependence of Titan’s surface composition, with water ice at latitudes beyond 30°N -30°S, while Titan’s 2.23 % 14.98 % equatorial region appears to be dominated by organics. 0.71 % 2.11 % The poles are dominated by fluvial and 18.60 % 61.37 % lacustrine processes (Lopes et al., 2020, Nature Geosciences) Ongoing work Organics & Water-ice dark + tholinwater-like- ice water-ice + tholin- Tholin-like + like water-ice dark + waterorganics-ice water-ice +
Load more

Recommended publications
  • Cassini RADAR Images at Hotei Arcus and Western Xanadu, Titan: Evidence for Geologically Recent Cryovolcanic Activity S
    GEOPHYSICAL RESEARCH LETTERS, VOL. 36, L04203, doi:10.1029/2008GL036415, 2009 Click Here for Full Article Cassini RADAR images at Hotei Arcus and western Xanadu, Titan: Evidence for geologically recent cryovolcanic activity S. D. Wall,1 R. M. Lopes,1 E. R. Stofan,2 C. A. Wood,3 J. L. Radebaugh,4 S. M. Ho¨rst,5 B. W. Stiles,1 R. M. Nelson,1 L. W. Kamp,1 M. A. Janssen,1 R. D. Lorenz,6 J. I. Lunine,5 T. G. Farr,1 G. Mitri,1 P. Paillou,7 F. Paganelli,2 and K. L. Mitchell1 Received 21 October 2008; revised 5 January 2009; accepted 8 January 2009; published 24 February 2009. [1] Images obtained by the Cassini Titan Radar Mapper retention age comparable with Earth or Venus (500 Myr) (RADAR) reveal lobate, flowlike features in the Hotei [Lorenz et al., 2007]). Arcus region that embay and cover surrounding terrains and [4] Most putative cryovolcanic features are located at mid channels. We conclude that they are cryovolcanic lava flows to high northern latitudes [Elachi et al., 2005; Lopes et al., younger than surrounding terrain, although we cannot reject 2007]. They are characterized by lobate boundaries and the sedimentary alternative. Their appearance is grossly relatively uniform radar properties, with flow features similar to another region in western Xanadu and unlike most brighter than their surroundings. Cryovolcanic flows are of the other volcanic regions on Titan. Both regions quite limited in area compared to the more extensive dune correspond to those identified by Cassini’s Visual and fields [Radebaugh et al., 2008] or lakes [Hayes et al., Infrared Mapping Spectrometer (VIMS) as having variable 2008].
    [Show full text]
  • Titan's Near Infrared Atmospheric Transmission and Surface
    40th Lunar and Planetary Science Conference (2009) 1863.pdf TITAN’S NEAR INFRARED ATMOSPHERIC TRANSMISSION AND SURFACE REFLECTANCE FROM THE CASSINI VISUAL AND INFRARED MAPPING SPECTROMETER. P. Hayne1,2 and T. B. McCord2, J. W. Barnes3, 1University of California, Los Angeles (595 Charles Young Drive East, Los Angeles, CA 90095; [email protected]), 2The Bear Fight Center (Winthrop, WA), 3University of Idaho (Moscow, ID). 1. Introduction: Titan’s near infrared spectrum is At the top of the atmosphere, the outgoing intensity is dominated by absorption by atmospheric methane. then Direct transmission of radiation from the surface ⎛ A 1 ⎞ (1) I↑ / I= A ⋅ e −τ(1/ μ1 + 1/ μ 2 ) +β ⋅ ⎜ e −τ/ μ1 + ⎟ through the full atmosphere is nearly zero, except in top 0 ⎜ μ μ ⎟ several methane “windows”. In these narrow spectral ⎝ 1 2 ⎠ regions, Titan’s surface is visible, but our view is akin where A is the (monochromatic) surface albedo, β ≡ to peering through a dirty window pane, due to both Γ/I0 is the ratio of the diffuse emergent intensity to the direct incident intensity at the top of the atmosphere, N2-induced pressure broadening of adjacent CH4 lines and multiple scattering by stratospheric haze particles. and μ2 is the cosine of the emergence angle. To solve Measured reflectance values in the methane windows Equation (1), we make an initial guess τ for the total are therefore only partially representative of true sur- optical depth, so that face albedo. ⎡ ⎛ A 1 ⎞⎤ (2) τ≈ − μ′lnII / −β ⋅⎜ ⋅e −τ/ μ1 + ⎟ + μ′ln A Using a simple radia- ⎢ 0 ⎜ ⎟⎥ ⎣ ⎝ μ1 μ 2 ⎠⎦ tive transfer model, we where μ′ ≡ /1 ( 1+ 1 ).
    [Show full text]
  • The Lakes and Seas of Titan • Explore Related Articles • Search Keywords Alexander G
    EA44CH04-Hayes ARI 17 May 2016 14:59 ANNUAL REVIEWS Further Click here to view this article's online features: • Download figures as PPT slides • Navigate linked references • Download citations The Lakes and Seas of Titan • Explore related articles • Search keywords Alexander G. Hayes Department of Astronomy and Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, New York 14853; email: [email protected] Annu. Rev. Earth Planet. Sci. 2016. 44:57–83 Keywords First published online as a Review in Advance on Cassini, Saturn, icy satellites, hydrology, hydrocarbons, climate April 27, 2016 The Annual Review of Earth and Planetary Sciences is Abstract online at earth.annualreviews.org Analogous to Earth’s water cycle, Titan’s methane-based hydrologic cycle This article’s doi: supports standing bodies of liquid and drives processes that result in common 10.1146/annurev-earth-060115-012247 Annu. Rev. Earth Planet. Sci. 2016.44:57-83. Downloaded from annualreviews.org morphologic features including dunes, channels, lakes, and seas. Like lakes Access provided by University of Chicago Libraries on 03/07/17. For personal use only. Copyright c 2016 by Annual Reviews. on Earth and early Mars, Titan’s lakes and seas preserve a record of its All rights reserved climate and surface evolution. Unlike on Earth, the volume of liquid exposed on Titan’s surface is only a small fraction of the atmospheric reservoir. The volume and bulk composition of the seas can constrain the age and nature of atmospheric methane, as well as its interaction with surface reservoirs. Similarly, the morphology of lacustrine basins chronicles the history of the polar landscape over multiple temporal and spatial scales.
    [Show full text]
  • The Exploration of Titan with an Orbiter and a Lake Probe
    Planetary and Space Science ∎ (∎∎∎∎) ∎∎∎–∎∎∎ Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss The exploration of Titan with an orbiter and a lake probe Giuseppe Mitri a,n, Athena Coustenis b, Gilbert Fanchini c, Alex G. Hayes d, Luciano Iess e, Krishan Khurana f, Jean-Pierre Lebreton g, Rosaly M. Lopes h, Ralph D. Lorenz i, Rachele Meriggiola e, Maria Luisa Moriconi j, Roberto Orosei k, Christophe Sotin h, Ellen Stofan l, Gabriel Tobie a,m, Tetsuya Tokano n, Federico Tosi o a Université de Nantes, LPGNantes, UMR 6112, 2 rue de la Houssinière, F-44322 Nantes, France b Laboratoire d’Etudes Spatiales et d’Instrumentation en Astrophysique (LESIA), Observatoire de Paris, CNRS, UPMC University Paris 06, University Paris-Diderot, Meudon, France c Smart Structures Solutions S.r.l., Rome, Italy d Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, United States e Dipartimento di Ingegneria Meccanica e Aerospaziale, Università La Sapienza, 00184 Rome, Italy f Institute of Geophysics and Planetary Physics, Department of Earth and Space Sciences, Los Angeles, CA, United States g LPC2E-CNRS & LESIA-Obs., Paris, France h Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States i Johns Hopkins University, Applied Physics Laboratory, Laurel, MD, United States j Istituto di Scienze dell‘Atmosfera e del Clima (ISAC), Consiglio Nazionale delle Ricerche (CNR), Rome, Italy k Istituto di Radioastronomia (IRA), Istituto Nazionale
    [Show full text]
  • AVIATR—Aerial Vehicle for In-Situ and Airborne Titan Reconnaissance a Titan Airplane Mission Concept
    Exp Astron DOI 10.1007/s10686-011-9275-9 ORIGINAL ARTICLE AVIATR—Aerial Vehicle for In-situ and Airborne Titan Reconnaissance A Titan airplane mission concept Jason W. Barnes · Lawrence Lemke · Rick Foch · Christopher P. McKay · Ross A. Beyer · Jani Radebaugh · David H. Atkinson · Ralph D. Lorenz · Stéphane Le Mouélic · Sebastien Rodriguez · Jay Gundlach · Francesco Giannini · Sean Bain · F. Michael Flasar · Terry Hurford · Carrie M. Anderson · Jon Merrison · Máté Ádámkovics · Simon A. Kattenhorn · Jonathan Mitchell · Devon M. Burr · Anthony Colaprete · Emily Schaller · A. James Friedson · Kenneth S. Edgett · Angioletta Coradini · Alberto Adriani · Kunio M. Sayanagi · Michael J. Malaska · David Morabito · Kim Reh Received: 22 June 2011 / Accepted: 10 November 2011 © The Author(s) 2011. This article is published with open access at Springerlink.com J. W. Barnes (B) · D. H. Atkinson · S. A. Kattenhorn University of Idaho, Moscow, ID 83844-0903, USA e-mail: [email protected] L. Lemke · C. P. McKay · R. A. Beyer · A. Colaprete NASA Ames Research Center, Moffett Field, CA, USA R. Foch · Sean Bain Naval Research Laboratory, Washington, DC, USA R. A. Beyer Carl Sagan Center at the SETI Institute, Mountain View, CA, USA J. Radebaugh Brigham Young University, Provo, UT, USA R. D. Lorenz Johns Hopkins University Applied Physics Laboratory, Silver Spring, MD, USA S. Le Mouélic Laboratoire de Planétologie et Géodynamique, CNRS, UMR6112, Université de Nantes, Nantes, France S. Rodriguez Université de Paris Diderot, Paris, France Exp Astron Abstract We describe a mission concept for a stand-alone Titan airplane mission: Aerial Vehicle for In-situ and Airborne Titan Reconnaissance (AVI- ATR). With independent delivery and direct-to-Earth communications, AVI- ATR could contribute to Titan science either alone or as part of a sustained Titan Exploration Program.
    [Show full text]
  • Cassini Observations of Flow-Like Features in Western Tui Regio, Titan, J.W
    Cassini observations of flow-like features in western Tui Regio, Titan, J.W. Barnes, R.H. Brown, J. Radebaugh, Buratti B. J., C. Sotin, Le Mouelic S., S. Rodriguez, Turtle E. P., J. Perry, R. Clark, et al. To cite this version: J.W. Barnes, R.H. Brown, J. Radebaugh, Buratti B. J., C. Sotin, et al.. Cassini observations of flow-like features in western Tui Regio, Titan,. Geophysical Research Letters, American Geophysical Union, 2006, 33, pp.l16204. 10.1029/2006gl026843. hal-00112109 HAL Id: hal-00112109 https://hal.archives-ouvertes.fr/hal-00112109 Submitted on 3 May 2021 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. GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L16204, doi:10.1029/2006GL026843, 2006 Cassini observations of flow-like features in western Tui Regio, Titan Jason W. Barnes,1 Robert H. Brown,1 Jani Radebaugh,1 Bonnie J. Buratti,2 Christophe Sotin,3 Stephane Le Mouelic,3 Sebastien Rodriguez,3 Elizabeth P. Turtle,1 Jason Perry,1 Roger Clark,4 Kevin H. Baines,2 and Phillip D. Nicholson5 Received 8 May 2006; revised 19 July 2006; accepted 24 July 2006; published 30 August 2006.
    [Show full text]
  • Production and Global Transport of Titan's Sand Particles
    Barnes et al. Planetary Science (2015) 4:1 DOI 10.1186/s13535-015-0004-y ORIGINAL RESEARCH Open Access Production and global transport of Titan’s sand particles Jason W Barnes1*,RalphDLorenz2, Jani Radebaugh3, Alexander G Hayes4,KarlArnold3 and Clayton Chandler3 *Correspondence: [email protected] Abstract 1Department of Physics, University Previous authors have suggested that Titan’s individual sand particles form by either of Idaho, Moscow, Idaho, 83844-0903 USA sintering or by lithification and erosion. We suggest two new mechanisms for the Full list of author information is production of Titan’s organic sand particles that would occur within bodies of liquid: available at the end of the article flocculation and evaporitic precipitation. Such production mechanisms would suggest discrete sand sources in dry lakebeds. We search for such sources, but find no convincing candidates with the present Cassini Visual and Infrared Mapping Spectrometer coverage. As a result we propose that Titan’s equatorial dunes may represent a single, global sand sea with west-to-east transport providing sources and sinks for sand in each interconnected basin. The sand might then be transported around Xanadu by fast-moving Barchan dune chains and/or fluvial transport in transient riverbeds. A river at the Xanadu/Shangri-La border could explain the sharp edge of the sand sea there, much like the Kuiseb River stops the Namib Sand Sea in southwest Africa on Earth. Future missions could use the composition of Titan’s sands to constrain the global hydrocarbon cycle. We chose to follow an unconventional format with respect to our choice of section head- ings compared to more conventional practice because the multifaceted nature of our work did not naturally lend itself to a logical progression within the precribed system.
    [Show full text]
  • Regional Geomorphology and History of Titan's Xanadu Province
    Icarus 211 (2011) 672–685 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Regional geomorphology and history of Titan’s Xanadu province J. Radebaugh a,, R.D. Lorenz b, S.D. Wall c, R.L. Kirk d, C.A. Wood e, J.I. Lunine f, E.R. Stofan g, R.M.C. Lopes c, P. Valora a, T.G. Farr c, A. Hayes h, B. Stiles c, G. Mitri c, H. Zebker i, M. Janssen c, L. Wye i, A. LeGall c, K.L. Mitchell c, F. Paganelli g, R.D. West c, E.L. Schaller j, The Cassini Radar Team a Department of Geological Sciences, Brigham Young University, S-389 ESC Provo, UT 84602, United States b Johns Hopkins Applied Physics Laboratory, Laurel, MD 20723, United States c Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, United States d US Geological Survey, Branch of Astrogeology, Flagstaff, AZ 86001, United States e Wheeling Jesuit University, Wheeling, WV 26003, United States f Department of Physics, University of Rome ‘‘Tor Vergata”, Rome 00133, Italy g Proxemy Research, P.O. Box 338, Rectortown, VA 20140, USA h Department of Geological Sciences, California Institute of Technology, Pasadena, CA 91125, USA i Department of Electrical Engineering, Stanford University, 350 Serra Mall, Stanford, CA 94305, USA j Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA article info abstract Article history: Titan’s enigmatic Xanadu province has been seen in some detail with instruments from the Cassini space- Received 20 March 2009 craft.
    [Show full text]
  • Implications for Titan's Surface Properties
    Icarus 208 (2010) 366–384 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Correlations between VIMS and RADAR data over the surface of Titan: Implications for Titan’s surface properties F. Tosi a,*, R. Orosei a, R. Seu b, A. Coradini a, J.I. Lunine a,c, G. Filacchione d, A.I. Gavrishin e, F. Capaccioni d, P. Cerroni d, A. Adriani a, M.L. Moriconi f, A. Negrão g, E. Flamini h, R.H. Brown i, L.C. Wye j, M. Janssen k, R.D. West k, J.W. Barnes l, S.D. Wall k, R.N. Clark m, D.P. Cruikshank n, T.B. McCord o, P.D. Nicholson p, J.M. Soderblom i, The Cassini VIMS and RADAR Teams a INAF-IFSI Istituto di Fisica dello Spazio Interplanetario, Via del Fosso del Cavaliere, 100, I-00133 Roma, Italy b Università degli Studi di Roma ‘‘La Sapienza”, Facoltà di Ingegneria, Dipartimento INFOCOM, Via Eudossiana 18, I-00184 Roma, Italy c Università degli Studi di Roma ‘‘Tor Vergata”, Dipartimento di Fisica, Via della Ricerca Scientifica 1, I-00133 Roma, Italy d INAF-IASF Istituto di Astrofisica Spaziale e Fisica Cosmica, Via del Fosso del Cavaliere 100, I-00133 Roma, Italy e South-Russian State Technical University, Prosveschenia 132, Novocherkassk 346428, Russia f CNR-ISAC Istituto di Scienze dell’Atmosfera e del Clima, Via del Fosso del Cavaliere 100, I-00133 Roma, Italy g Escola Superior de Tecnologia e Gestão do Instituto Politécnico de Leiria (ESTG-IPL), Campus 2 Morro do Lena – Alto do Vieiro, 2411-901 Leiria, Portugal h Agenzia Spaziale Italiana, Viale Liegi 26, I-00198 Roma, Italy i Lunar and Planetary Lab and Steward Observatory, University of Arizona, 1629 E.
    [Show full text]
  • Structural and Tidal Models of Titan and Inferences on Cryovolcanism
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Institute of Transport Research:Publications JournalofGeophysicalResearch: Planets RESEARCH ARTICLE Structural and tidal models of Titan and inferences 10.1002/2013JE004512 on cryovolcanism Key Points: F. Sohl1, A. Solomonidou2,3,4, F. W. Wagner1,5, A. Coustenis2, H. Hussmann1, and D. Schulze-Makuch6,7 • Interior models and amplitude patterns of diurnal tidal stresses 1DLR, Institute of Planetary Research, Berlin, Germany, 2LESIA, Observatoire de Paris, CNRS, UPMC University Paris 06, are calculated University Paris-Diderot-Meudon, Paris, France, 3Department of Geology and Geoenvironment, National and Kapodistrian • The diurnal tidal stress pattern 4 is compliant with cryovolcanic University of Athens, Athens, Greece, Now at Jet Propulsion Laboratory, California Institute of Technology, Pasadena, 5 6 candidate areas California, USA, Westphalian Wilhelms-University, Institute for Planetology, Münster, Germany, School of Earth and • A warm, low-ammonia ocean could Environmental Sciences, Washington State University, Pullman, Washington, USA, 7Center for Astronomy and increase Titan’s habitable potential Astrophysics, Technical University of Berlin, Berlin, Germany Correspondence to: F. Sohl, Abstract Titan, Saturn’s largest satellite, is subject to solid body tides exerted by Saturn on the timescale [email protected] of its orbital period. The tide-induced internal redistribution of mass results in tidal stress variations, which could play a major role for Titan’s geologic surface record. We construct models of Titan’s interior that are Citation: consistent with the satellite’s mean density, polar moment-of-inertia factor, obliquity, and tidal potential Sohl, F., A. Solomonidou, F. W.
    [Show full text]
  • Distribution and Intensity of Water Ice Signature in South Xanadu and Tui Regio
    EPSC Abstracts Vol. 14, EPSC2020-188, 2020 https://doi.org/10.5194/epsc2020-188 Europlanet Science Congress 2020 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Distribution and intensity of water ice signature in South Xanadu and Tui Regio Maélie Coutelier1, Daniel Cordier1, Pascal Rannou1, and Benoît Seignovert2 1Groupe de Spectroscopie Moléclaire et Atmosphérique - UMR CNRS 7331, Université de Reims Champagne-Ardenne, Reims, France ([email protected]) 2Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA Titan is a complexe moon of Saturn, with dense atmosphere, hydrocarbon cycle, and water-ice crust. Titan was targeted by two major space missions: Voyager and Cassini, and has been the subject of many studies. Lakes and seas of liquid hydrocarbons were discovered by Cassini's RADAR in Titan's polar regions [15, 14]. This instrument also detected on equatorial regions geomorphological structures related to the presence of liquid, like fluvial valleys incised in the bedrock, and alluvial fans [8, 3]. The existence of evaporitic terrains where also suggested [1, 4, 9], often in place of paleo-sea [12]. Water ice signal is not present everywhere on Titan, contrary to other icy moon of Saturn and Jupiter. It was detected with Cassini's VIMS instrument in Titan's dark region, often at the transition between a dark and bright unit, and mixed with a darkening material [11, 13]. Ref. [6] also highlighted an equatorial corridor of exposed water-ice using a principal component analysis (PCA) with VIMS, showing on a large scale terrains with low and high water ice content.
    [Show full text]
  • Bulletin of the Geological Society of Greece
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by National Documentation Centre - EKT journals Bulletin of the Geological Society of Greece Vol. 43, 2010 MODELLING OF VOLCANIC ERUPTIONS ON TITAN Solomonidou A. Fortes A.D. Kyriakopoulos K. https://doi.org/10.12681/bgsg.11679 Copyright © 2017 A. Solomonidou, A.D. Fortes, K. Kyriakopoulos To cite this article: Solomonidou, A., Fortes, A., & Kyriakopoulos, K. (2010). MODELLING OF VOLCANIC ERUPTIONS ON TITAN. Bulletin of the Geological Society of Greece, 43(5), 2726-2738. doi:https://doi.org/10.12681/bgsg.11679 http://epublishing.ekt.gr | e-Publisher: EKT | Downloaded at 20/02/2020 22:04:53 | Δελτίο της Ελληνικής Γεωλογικής Εταιρίας, 2010 Bulletin of the Geological Society of Greece, 2010 Πρακτικά 12ου Διεθνούς Συνεδρίου Proceedings of the 12th International Congress Πάτρα, Μάιος 2010 Patras, May, 2010 MODELLING OF VOLCANIC ERUPTIONS ON TITAN Solomonidou A. 1,2,3, Fortes A.D.3, Kyriakopoulos K.1 1 National & Kapodistrian University of Athens, Department of Geology and Geoenvironment, Athens, Greece ([email protected])., 2 LESIA, Observatoire de Paris – Meudon, Meudon Cedex, France ([email protected])., 3 University College London, Department of Earth Sciences, London, UK. Abstract Observations by the Visual Infrared Spectrometer instrument (VIMS) aboard the Cassini mission have indicated the possible presence of CO2 ice on the surface on Titan, in areas which exhibit high reflectance in specific spectral windows (McCord et al., 2008). Two of the bright spots of significance are located within the Xanadu region – Tui Regio (located at 20°S, 130°W) and Hotei Regio (located at 26°S, 78°W), and there is a further spot situated in proximity to Omacatl Macula (Hayne et al., 2008).
    [Show full text]