Exploring Planetary Moons
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Lab 7: Gravity and Jupiter's Moons
Lab 7: Gravity and Jupiter's Moons Image of Galileo Spacecraft Gravity is the force that binds all astronomical structures. Clusters of galaxies are gravitationally bound into the largest structures in the Universe, Galactic Superclusters. The galaxies themselves are held together by gravity, as are all of the star systems within them. Our own Solar System is a collection of bodies gravitationally bound to our star, Sol. Cutting edge science requires the use of Einstein's General Theory of Relativity to explain gravity. But the interactions of the bodies in our Solar System were understood long before Einstein's time. In chapter two of Chaisson McMillan's Astronomy Today, you went over Kepler's Laws. These laws of gravity were made to describe the interactions in our Solar System. P2=a3/M Where 'P' is the orbital period in Earth years, the time for the body to make one full orbit. 'a' is the length of the orbit's semi-major axis, for nearly circular orbits the orbital radius. 'M' is the total mass of the system in units of Solar Masses. Jupiter System Montage picture from NASA ID = PIA01481 Jupiter has over 60 moons at the last count, most of which are asteroids and comets captured from Written by Meagan White and Paul Lewis Page 1 the Asteroid Belt. When Galileo viewed Jupiter through his early telescope, he noticed only four moons: Io, Europa, Ganymede, and Callisto. The Jupiter System can be thought of as a miniature Solar System, with Jupiter in place of the Sun, and the Galilean moons like planets. -
A Wunda-Full World? Carbon Dioxide Ice Deposits on Umbriel and Other Uranian Moons
Icarus 290 (2017) 1–13 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus A Wunda-full world? Carbon dioxide ice deposits on Umbriel and other Uranian moons ∗ Michael M. Sori , Jonathan Bapst, Ali M. Bramson, Shane Byrne, Margaret E. Landis Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA a r t i c l e i n f o a b s t r a c t Article history: Carbon dioxide has been detected on the trailing hemispheres of several Uranian satellites, but the exact Received 22 June 2016 nature and distribution of the molecules remain unknown. One such satellite, Umbriel, has a prominent Revised 28 January 2017 high albedo annulus-shaped feature within the 131-km-diameter impact crater Wunda. We hypothesize Accepted 28 February 2017 that this feature is a solid deposit of CO ice. We combine thermal and ballistic transport modeling to Available online 2 March 2017 2 study the evolution of CO 2 molecules on the surface of Umbriel, a high-obliquity ( ∼98 °) body. Consid- ering processes such as sublimation and Jeans escape, we find that CO 2 ice migrates to low latitudes on geologically short (100s–1000 s of years) timescales. Crater morphology and location create a local cold trap inside Wunda, and the slopes of crater walls and a central peak explain the deposit’s annular shape. The high albedo and thermal inertia of CO 2 ice relative to regolith allows deposits 15-m-thick or greater to be stable over the age of the solar system. -
Exomoon Habitability Constrained by Illumination and Tidal Heating
submitted to Astrobiology: April 6, 2012 accepted by Astrobiology: September 8, 2012 published in Astrobiology: January 24, 2013 this updated draft: October 30, 2013 doi:10.1089/ast.2012.0859 Exomoon habitability constrained by illumination and tidal heating René HellerI , Rory BarnesII,III I Leibniz-Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany, [email protected] II Astronomy Department, University of Washington, Box 951580, Seattle, WA 98195, [email protected] III NASA Astrobiology Institute – Virtual Planetary Laboratory Lead Team, USA Abstract The detection of moons orbiting extrasolar planets (“exomoons”) has now become feasible. Once they are discovered in the circumstellar habitable zone, questions about their habitability will emerge. Exomoons are likely to be tidally locked to their planet and hence experience days much shorter than their orbital period around the star and have seasons, all of which works in favor of habitability. These satellites can receive more illumination per area than their host planets, as the planet reflects stellar light and emits thermal photons. On the contrary, eclipses can significantly alter local climates on exomoons by reducing stellar illumination. In addition to radiative heating, tidal heating can be very large on exomoons, possibly even large enough for sterilization. We identify combinations of physical and orbital parameters for which radiative and tidal heating are strong enough to trigger a runaway greenhouse. By analogy with the circumstellar habitable zone, these constraints define a circumplanetary “habitable edge”. We apply our model to hypothetical moons around the recently discovered exoplanet Kepler-22b and the giant planet candidate KOI211.01 and describe, for the first time, the orbits of habitable exomoons. -
Phobos, Deimos: Formation and Evolution Alex Soumbatov-Gur
Phobos, Deimos: Formation and Evolution Alex Soumbatov-Gur To cite this version: Alex Soumbatov-Gur. Phobos, Deimos: Formation and Evolution. [Research Report] Karpov institute of physical chemistry. 2019. hal-02147461 HAL Id: hal-02147461 https://hal.archives-ouvertes.fr/hal-02147461 Submitted on 4 Jun 2019 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. Phobos, Deimos: Formation and Evolution Alex Soumbatov-Gur The moons are confirmed to be ejected parts of Mars’ crust. After explosive throwing out as cone-like rocks they plastically evolved with density decays and materials transformations. Their expansion evolutions were accompanied by global ruptures and small scale rock ejections with concurrent crater formations. The scenario reconciles orbital and physical parameters of the moons. It coherently explains dozens of their properties including spectra, appearances, size differences, crater locations, fracture symmetries, orbits, evolution trends, geologic activity, Phobos’ grooves, mechanism of their origin, etc. The ejective approach is also discussed in the context of observational data on near-Earth asteroids, main belt asteroids Steins, Vesta, and Mars. The approach incorporates known fission mechanism of formation of miniature asteroids, logically accounts for its outliers, and naturally explains formations of small celestial bodies of various sizes. -
Planetary Nomenclature: an Overview and Update
3rd Planetary Data Workshop 2017 (LPI Contrib. No. 1986) 7119.pdf PLANETARY NOMENCLATURE: AN OVERVIEW AND UPDATE. T. Gaither1, R. K. Hayward1, J. Blue1, L. Gaddis1, R. Schulz2, K. Aksnes3, G. Burba4, G. Consolmagno5, R. M. C. Lopes6, P. Masson7, W. Sheehan8, B.A. Smith9, G. Williams10, C. Wood11, 1USGS Astrogeology Science Center, Flagstaff, Ar- izona ([email protected]); 2ESA Scientific Support Office, Noordwijk, The Netherlands; 3Institute for Theoretical Astrophysics, Oslo, Norway; 4Vernadsky Institute, Moscow, Russia; 5Specola Vaticana, Vati- can City State; 6Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California; 7Uni- versite de Paris-Sud, Orsay, France; 8Lowell Observatory, Flagstaff, Arizona; 9Santa Fe, New Mexico; 10Minor Planet Center, Cambridge, Massachusetts; 11Planetary Science Institute, Tucson, Arizona. Introduction: The task of naming planetary Asteroids surface features, rings, and natural satellites is Ceres 113 managed by the International Astronomical Un- Dactyl 2 ion’s (IAU) Working Group for Planetary System Eros 41 Nomenclature (WGPSN). The members of the Gaspra 34 WGPSN and its task groups have worked since the Ida 25 early 1970s to provide a clear, unambiguous sys- Itokawa 17 tem of planetary nomenclature that represents cul- Lutetia 37 tures and countries from all regions of Earth. Mathilde 23 WGPSN members include Rita Schulz (chair) and Steins 24 9 other members representing countries around the Vesta 106 globe (see author list). In 2013, Blue et al. [1] pre- Jupiter sented an overview of planetary nomenclature, and Amalthea 4 in 2016 Hayward et al. [2] provided an update to Thebe 1 this overview. Given the extensive planetary ex- Io 224 ploration and research that has taken place since Europa 111 2013, it is time to update the community on the sta- Ganymede 195 tus of planetary nomenclature, the purpose and Callisto 153 rules, the process for submitting name requests, and the IAU approval process. -
Terrestrial Impact Structures Provide the Only Ground Truth Against Which Computational and Experimental Results Can Be Com Pared
Ann. Rev. Earth Planet. Sci. 1987. 15:245-70 Copyright([;; /987 by Annual Reviews Inc. All rights reserved TERRESTRIAL IMI!ACT STRUCTURES ··- Richard A. F. Grieve Geophysics Division, Geological Survey of Canada, Ottawa, Ontario KIA OY3, Canada INTRODUCTION Impact structures are the dominant landform on planets that have retained portions of their earliest crust. The present surface of the Earth, however, has comparatively few recognized impact structures. This is due to its relative youthfulness and the dynamic nature of the terrestrial geosphere, both of which serve to obscure and remove the impact record. Although not generally viewed as an important terrestrial (as opposed to planetary) geologic process, the role of impact in Earth evolution is now receiving mounting consideration. For example, large-scale impact events may hav~~ been responsible for such phenomena as the formation of the Earth's moon and certain mass extinctions in the biologic record. The importance of the terrestrial impact record is greater than the relatively small number of known structures would indicate. Impact is a highly transient, high-energy event. It is inherently difficult to study through experimentation because of the problem of scale. In addition, sophisticated finite-element code calculations of impact cratering are gen erally limited to relatively early-time phenomena as a result of high com putational costs. Terrestrial impact structures provide the only ground truth against which computational and experimental results can be com pared. These structures provide information on aspects of the third dimen sion, the pre- and postimpact distribution of target lithologies, and the nature of the lithologic and mineralogic changes produced by the passage of a shock wave. -
Transit Timing Analysis of the Hot Jupiters WASP-43B and WASP-46B and the Super Earth Gj1214b
Transit timing analysis of the hot Jupiters WASP-43b and WASP-46b and the super Earth GJ1214b Mathias Polfliet Promotors: Michaël Gillon, Maarten Baes 1 Abstract Transit timing analysis is proving to be a promising method to detect new planetary partners in systems which already have known transiting planets, particularly in the orbital resonances of the system. In these resonances we might be able to detect Earth-mass objects well below the current detection and even theoretical (due to stellar variability) thresholds of the radial velocity method. We present four new transits for WASP-46b, four new transits for WASP-43b and eight new transits for GJ1214b observed with the robotic telescope TRAPPIST located at ESO La Silla Observatory, Chile. Modelling the data was done using several Markov Chain Monte Carlo (MCMC) simulations of the new transits with old data and a collection of transit timings for GJ1214b from published papers. For the hot Jupiters this lead to a general increase in accuracy for the physical parameters of the system (for the mass and period we found: 2.034±0.052 MJup and 0.81347460±0.00000048 days and 2.03±0.13 MJup and 1.4303723±0.0000011 days for WASP-43b and WASP-46b respectively). For GJ1214b this was not the case given the limited photometric precision of TRAPPIST. The additional timings however allowed us to constrain the period to 1.580404695±0.000000084 days and the RMS of the TTVs to 16 seconds. We investigated given systems for Transit Timing Variations (TTVs) and variations in the other transit parameters and found no significant (3sv) deviations. -
The Minor Planet Bulletin
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 36, NUMBER 3, A.D. 2009 JULY-SEPTEMBER 77. PHOTOMETRIC MEASUREMENTS OF 343 OSTARA Our data can be obtained from http://www.uwec.edu/physics/ AND OTHER ASTEROIDS AT HOBBS OBSERVATORY asteroid/. Lyle Ford, George Stecher, Kayla Lorenzen, and Cole Cook Acknowledgements Department of Physics and Astronomy University of Wisconsin-Eau Claire We thank the Theodore Dunham Fund for Astrophysics, the Eau Claire, WI 54702-4004 National Science Foundation (award number 0519006), the [email protected] University of Wisconsin-Eau Claire Office of Research and Sponsored Programs, and the University of Wisconsin-Eau Claire (Received: 2009 Feb 11) Blugold Fellow and McNair programs for financial support. References We observed 343 Ostara on 2008 October 4 and obtained R and V standard magnitudes. The period was Binzel, R.P. (1987). “A Photoelectric Survey of 130 Asteroids”, found to be significantly greater than the previously Icarus 72, 135-208. reported value of 6.42 hours. Measurements of 2660 Wasserman and (17010) 1999 CQ72 made on 2008 Stecher, G.J., Ford, L.A., and Elbert, J.D. (1999). “Equipping a March 25 are also reported. 0.6 Meter Alt-Azimuth Telescope for Photometry”, IAPPP Comm, 76, 68-74. We made R band and V band photometric measurements of 343 Warner, B.D. (2006). A Practical Guide to Lightcurve Photometry Ostara on 2008 October 4 using the 0.6 m “Air Force” Telescope and Analysis. Springer, New York, NY. located at Hobbs Observatory (MPC code 750) near Fall Creek, Wisconsin. -
Warfare in a Fragile World: Military Impact on the Human Environment
Recent Slprt•• books World Armaments and Disarmament: SIPRI Yearbook 1979 World Armaments and Disarmament: SIPRI Yearbooks 1968-1979, Cumulative Index Nuclear Energy and Nuclear Weapon Proliferation Other related •• 8lprt books Ecological Consequences of the Second Ihdochina War Weapons of Mass Destruction and the Environment Publish~d on behalf of SIPRI by Taylor & Francis Ltd 10-14 Macklin Street London WC2B 5NF Distributed in the USA by Crane, Russak & Company Inc 3 East 44th Street New York NY 10017 USA and in Scandinavia by Almqvist & WikseH International PO Box 62 S-101 20 Stockholm Sweden For a complete list of SIPRI publications write to SIPRI Sveavagen 166 , S-113 46 Stockholm Sweden Stoekholol International Peace Research Institute Warfare in a Fragile World Military Impact onthe Human Environment Stockholm International Peace Research Institute SIPRI is an independent institute for research into problems of peace and conflict, especially those of disarmament and arms regulation. It was established in 1966 to commemorate Sweden's 150 years of unbroken peace. The Institute is financed by the Swedish Parliament. The staff, the Governing Board and the Scientific Council are international. As a consultative body, the Scientific Council is not responsible for the views expressed in the publications of the Institute. Governing Board Dr Rolf Bjornerstedt, Chairman (Sweden) Professor Robert Neild, Vice-Chairman (United Kingdom) Mr Tim Greve (Norway) Academician Ivan M£ilek (Czechoslovakia) Professor Leo Mates (Yugoslavia) Professor -
The Moon (~1700Km) an Asteroid (~50Km)
1) inventory Solar System 2) spin/orbit/shape 3) heated by the Sun overview 4) how do we fnd out Inventory 1 star (99.9% of M) 8 planets (99.9% of L) - Terrestrial: Mercury Venus Earth Mars - Giant: Jupiter Saturn Uranus Neptune Lots of small bodies incl. dwarf planets Ceres Pluto Eris Maybe a 9th planet? Moons of Jupiter Inventory (cont'd) 4 Galilean satellites (Ganymede, Callisto, Io & Europa), 3 Many moons & rings ~10 km (close to Jupiter, likely primordial) Mercury: 0 Venus: 0 Earth: 1 (1700km) Mars: 2 (~10km) Jupiter: 69 + rings Saturn: 62 + rings Uranus: 27 + rings Neptune: 14 + rings 2001J3: 4km Even among dwarf planets, asteroids, Kuiper belt objects, and comets. E.g., Pluto: 5 Eris: 1 Moons of Mars: Deimos & Phobos, ~10km Atmosphere no thick thick little thick Inventory (cont'd) ~105 known small objects in the - Asteroid belt (Ceres ~300 km) - Kuiper belt (Eris, Pluto, Sedna, Quaoar, ~1000 km) Estimated: ~1012 comets in the - Oort cloud (~ 104 AU) Associated: - zodiacal dust (fre-works on the sky: comets & meteorites) What are planets? IAU (for solar system): Orbits Sun, massive enough to be round and to have cleared its neighbourhood. More general: 6 1) no nuclear fusion (not even deuterium): Tc < 10 K 2) pressure provided by electron degeneracy and/or Coulomb force (l ~ h/p ~ d) (d ~ atomic radius) 3) can be solid or gaseous (with solid cores) --- similar density Mass & Mean r M [g/cm3] R~M J Jupiter 1.0 1.33 R R~M1/3 Saturn 0.3 0.77 R~M-1/3 Neptune 0.05 1.67 Uranus 0.04 1.24 Earth 0.003 5.52 Venus 0.002 5.25 planets brown dwarfs stars Mars 0.0003 3.93 Mercury 0.0002 5.43 3 MJ 13 MJ 80 MJ M Orbits inclination: largely coplanar (history) direction: all the same eccentricity: a few percent (except for Mercury) Titus-Bode (ftting) law (1766) planetary orbits appear to (almost) satisfy a single relation 'Predict' the existence of the asteroid belt (1801: Ceres discovered) coincidence or something deeper? other systems? Computer simulations indicate that planets are as maximally packed as allowed by stability. -
Lecture 12 the Rings and Moons of the Outer Planets October 15, 2018
Lecture 12 The Rings and Moons of the Outer Planets October 15, 2018 1 2 Rings of Outer Planets • Rings are not solid but are fragments of material – Saturn: Ice and ice-coated rock (bright) – Others: Dusty ice, rocky material (dark) • Very thin – Saturn rings ~0.05 km thick! • Rings can have many gaps due to small satellites – Saturn and Uranus 3 Rings of Jupiter •Very thin and made of small, dark particles. 4 Rings of Saturn Flash movie 5 Saturn’s Rings Ring structure in natural color, photographed by Cassini probe July 23, 2004. Click on image for Astronomy Picture of the Day site, or here for JPL information 6 Saturn’s Rings (false color) Photo taken by Voyager 2 on August 17, 1981. Click on image for more information 7 Saturn’s Ring System (Cassini) Mars Mimas Janus Venus Prometheus A B C D F G E Pandora Enceladus Epimetheus Earth Tethys Moon Wikipedia image with annotations On July 19, 2013, in an event celebrated the world over, NASA's Cassini spacecraft slipped into Saturn's shadow and turned to image the planet, seven of its moons, its inner rings -- and, in the background, our home planet, Earth. 8 Newly Discovered Saturnian Ring • Nearly invisible ring in the plane of the moon Pheobe’s orbit, tilted 27° from Saturn’s equatorial plane • Discovered by the infrared Spitzer Space Telescope and announced 6 October 2009 • Extends from 128 to 207 Saturnian radii and is about 40 radii thick • Contributes to the two-tone coloring of the moon Iapetus • Click here for more info about the artist’s rendering 9 Rings of Uranus • Uranus -- rings discovered through stellar occultation – Rings block light from star as Uranus moves by. -
The Rings and Inner Moons of Uranus and Neptune: Recent Advances and Open Questions
Workshop on the Study of the Ice Giant Planets (2014) 2031.pdf THE RINGS AND INNER MOONS OF URANUS AND NEPTUNE: RECENT ADVANCES AND OPEN QUESTIONS. Mark R. Showalter1, 1SETI Institute (189 Bernardo Avenue, Mountain View, CA 94043, mshowal- [email protected]! ). The legacy of the Voyager mission still dominates patterns or “modes” seem to require ongoing perturba- our knowledge of the Uranus and Neptune ring-moon tions. It has long been hypothesized that numerous systems. That legacy includes the first clear images of small, unseen ring-moons are responsible, just as the nine narrow, dense Uranian rings and of the ring- Ophelia and Cordelia “shepherd” ring ε. However, arcs of Neptune. Voyager’s cameras also first revealed none of the missing moons were seen by Voyager, sug- eleven small, inner moons at Uranus and six at Nep- gesting that they must be quite small. Furthermore, the tune. The interplay between these rings and moons absence of moons in most of the gaps of Saturn’s rings, continues to raise fundamental dynamical questions; after a decade-long search by Cassini’s cameras, sug- each moon and each ring contributes a piece of the gests that confinement mechanisms other than shep- story of how these systems formed and evolved. herding might be viable. However, the details of these Nevertheless, Earth-based observations have pro- processes are unknown. vided and continue to provide invaluable new insights The outermost µ ring of Uranus shares its orbit into the behavior of these systems. Our most detailed with the tiny moon Mab. Keck and Hubble images knowledge of the rings’ geometry has come from spanning the visual and near-infrared reveal that this Earth-based stellar occultations; one fortuitous stellar ring is distinctly blue, unlike any other ring in the solar alignment revealed the moon Larissa well before Voy- system except one—Saturn’s E ring.