24. Satellites of the Giants

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Astronomy 241: Foundations of Astrophysics I 24. Satellites of the Giants White House Astronomy Night: IfA Events McCarthy Mall (near Hamilton): 11 am — 1 pm Solar Viewing Kapiolani Park (Zoo entrance): 7 pm — 10 pm Stargazing (Moon, Saturn) + 59 more Inventory of Moons • 6 large moons (D>1500 km) + 53 more — most internally active • 12 medium (D>300 km) — some activity in past? + 22 more • 145+ small (D>1 km) — no internal activity + 11 more Large & Medium Moons • spherical due to self-gravity • composed of ices & rock • most* formed in disks around parent planets • most* orbit in same direction as planets spin Triton is exception! The Jupiter Satellite Page Activity: Galilean Satellites IO EUROPA GANYMEDE CALLISTO Wide range of geological activity: — Io is most volcanic object in solar system! — Callisto exhibits very little activity. Ganymede and Callisto Global Callisto in Color Ganymede has a mixture of Callisto has a old and very old and new terrain, and hints heavily cratered terrain, with of tectonic activity. a possible subsurface ocean. Europa: an Ice-Covered Ocean? Fractures in crust Pwyll: Natural and False Impact Color Views of Europa crater Exaggerated colors “Natural” colors Europa: Rafts of Ice Europa - Ice Rafting View Europa: Internal Structure What warms Europa’s subsurface ocean? Io: Volcanic Moon Loki Patera: active center Pele: Io’s largest volcanic pluume Topography and Volcanos on Io Io: Volcanic Moon Ongoing Volcanic Eruption at Tvashtar Catena Tvashtar’s Plume Why so active? Tidal Heating of Io Jupiter Io is alternately stretched and squeezed in its elliptical orbit around Jupiter, creating heat through friction. Over time, this friction should make Io’s orbit more and more circular; what keeps Io’s orbit elliptical? 2:1 Mean-Motion Resonance m1 m2 M 2:1 Mean-Motion Resonance m1 = 0.001 M m2 = 0 P1:P2 = 2:1 2:1 Mean-Motion Resonance Laplace Resonance: Io, Europa, & Ganymede 4:2:1 Mean-Motion Resonance.

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Appendix 1: Io's Hot Spots Rosaly M
Appendix 1: Io's hot spots Rosaly M. C. Lopes,Jani Radebaugh,Melissa Meiner,Jason Perry,and Franck Marchis Detections of plumes and hot spots by Galileo, Voyager, HST, and ground-based observations. Notes and sources . (N) NICMOS hot spots detected by Goguen etal . (1998). (D) Hot spots detected by C. Dumas etal . in 1997 and/or 1998 (pers. commun.). Keck are hot spots detected by de Pater etal . (2004) and Marchis etal . (2001) from the Keck telescope using Adaptive Optics. (V, G, C) indicate Voyager, Galileo,orCassini detection. Other ground-based hot spots detected by Spencer etal . (1997a). Galileo PPR detections from Spencer etal . (2000) and Rathbun etal . (2004). Galileo SSIdetections of hot spots, plumes, and surface changes from McEwen etal . (1998, 2000), Geissler etal . (1999, 2004), Kezthelyi etal. (2001), and Turtle etal . (2004). Galileo NIMS detections prior to orbit C30 from Lopes-Gautier etal . (1997, 1999, 2000), Lopes etal . (2001, 2004), and Williams etal . (2004). Locations of surface features are approximate center of caldera or feature. References de Pater, I., F. Marchis, B. A. Macintosh, H. G. Rose, D. Le Mignant, J. R. Graham, and A. G. Davies. 2004. Keck AO observations of Io in and out of eclipse. Icarus, 169, 250±263. 308 Appendix 1: Io's hot spots Goguen, J., A. Lubenow, and A. Storrs. 1998. HST NICMOS images of Io in Jupiter's shadow. Bull. Am. Astron. Assoc., 30, 1120. Geissler, P. E., A. S. McEwen, L. Keszthelyi, R. Lopes-Gautier, J. Granahan, and D. P. Simonelli. 1999. Global color variations on Io. Icarus, 140(2), 265±281.
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Io Observer SDT to Steer a Comprehensive Mission Concept Study for the Next Decadal Survey
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A New Stereo Topographic Map of Io: Implications for Geology from Global
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ALMA Observations of Io Going Into and Coming out of Eclipse
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Loki Patera As a Magma Sea Dennis L
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EPSC2015-351, 2015 European Planetary Science Congress 2015 Eeuropeapn Planetarsy Science Ccongress C Author(S) 2015
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Keck AO Survey of Io Global Volcanic Activity Between 2 and 5 Mu M
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Planetary Geological Processes
See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/301371064 Planetary geological processes Conference Paper · November 2014 DOI: 10.1063/1.4902843 CITATIONS READS 0 2,860 2 authors: Rosaly M. Lopes Anezina Solomonidou NASA European Space Agency 405 PUBLICATIONS 7,240 CITATIONS 103 PUBLICATIONS 399 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Thermophysical, Rheological, and Mechanical, Property Measurements on Icy Compositions with Application to Solar System Ices View project Titan alluvial and fluvial fans View project All content following this page was uploaded by Rosaly M. Lopes on 22 June 2016. The user has requested enhancement of the downloaded file. Planetary Geological Processes Rosaly M.C. Lopesa and Anezina Solomonidoua,b aJet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 bLESIA - Observatoire de Paris, CNRS, UPMC Univ. Paris 06, Univ. Paris-Diderot – Meudon, 92195 Meudon Cedex, France Abstract. In this introduction to planetary geology, we review the major geologic processes affecting the solid bodies of the solar system, namely volcanism, tectonism, impact cratering, and erosion. We illustrate the interplay of these processes in different worlds, briefly reviewing how they affect the surfaces of the Earth’s Moon, Mercury, Venus and Mars, then focusing on two very different worlds: Jupiter’s moon Io, the most volcanically active object in the solar system, and Saturn’s moon Titan, where the interaction between a dense atmosphere and the surface make for remarkably earth-like landscapes despite the great differences in surface temperature and composition.
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Loki, Io: New Groundbased Observations and a Model Describing the Change from Periodic Overturn J. A. Rathbun – Department Of
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