Moons in Comparison
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The Geology of the Rocky Bodies Inside Enceladus, Europa, Titan, and Ganymede
49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083) 2905.pdf THE GEOLOGY OF THE ROCKY BODIES INSIDE ENCELADUS, EUROPA, TITAN, AND GANYMEDE. Paul K. Byrne1, Paul V. Regensburger1, Christian Klimczak2, DelWayne R. Bohnenstiehl1, Steven A. Hauck, II3, Andrew J. Dombard4, and Douglas J. Hemingway5, 1Planetary Research Group, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USA ([email protected]), 2Department of Geology, University of Georgia, Athens, GA 30602, USA, 3Department of Earth, Environmental, and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106, USA, 4Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA, 5Department of Earth & Planetary Science, University of California Berkeley, Berkeley, CA 94720, USA. Introduction: The icy satellites of Jupiter and horizontal stresses, respectively, Pp is pore fluid Saturn have been the subjects of substantial geological pressure (found from (3)), and μ is the coefficient of study. Much of this work has focused on their outer friction [12]. Finally, because equations (4) and (5) shells [e.g., 1–3], because that is the part most readily assess failure in the brittle domain, we also considered amenable to analysis. Yet many of these satellites ductile deformation with the relation n –E/RT feature known or suspected subsurface oceans [e.g., 4– ε̇ = C1σ exp , (6) 6], likely situated atop rocky interiors [e.g., 7], and where ε̇ is strain rate, C1 is a constant, σ is deviatoric several are of considerable astrobiological significance. stress, n is the stress exponent, E is activation energy, R For example, chemical reactions at the rock–water is the universal gas constant, and T is temperature [13]. -
Astronomy 330 HW 2 Presentations Outline
Astronomy 330 HW 2 •! Stanley Swat This class (Lecture 12): http://www.ufohowto.com/ Life in the Solar System •! Lucas Guthrie Next Class: http://www.crystalinks.com/abduction.html Life in the Solar System HW 5 is due Wednesday Music: We Are All Made of Stars– Moby Presentations Outline •! Daniel Borup •! Life on Venus? Futurama •! Life on Mars? Life in the Solar System? Earth – Venus comparison •! We want to examine in more detail the backyard of humans. •! What we find may change our estimates of ne. Radius 0.95 Earth Surface gravity 0.91 Earth Venus is the hottest Mass 0.81 Earth planet, the closest in Distance from Sun 0.72 AU size to Earth, the closest Average Temp 475 C in distance to Earth, and Year 224.7 Earth days the planet with the Length of Day 116.8 Earth days longest day. Atmosphere 96% CO2 What We Used to Think Turns Out that Venus is Hell Venus must be hotter, as it is closer the Sun, but the cloud •! The surface is hot enough to melt lead cover must reflect back a large amount of the heat. •! There is a runaway greenhouse effect •! There is almost no water In 1918, a Swedish chemist and Nobel laureate concluded: •! There is sulfuric acid rain •! Everything on Venus is dripping wet. •! Most of the surface is no doubt covered with swamps. •! Not a place to visit for Spring Break. •! The constantly uniform climatic conditions result in an entire absence of adaptation to changing exterior conditions. •! Only low forms of life are therefore represented, mostly no doubt, belonging to the vegetable kingdom; and the organisms are nearly of the same kind all over the planet. -
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. -
JUICE Red Book
ESA/SRE(2014)1 September 2014 JUICE JUpiter ICy moons Explorer Exploring the emergence of habitable worlds around gas giants Definition Study Report European Space Agency 1 This page left intentionally blank 2 Mission Description Jupiter Icy Moons Explorer Key science goals The emergence of habitable worlds around gas giants Characterise Ganymede, Europa and Callisto as planetary objects and potential habitats Explore the Jupiter system as an archetype for gas giants Payload Ten instruments Laser Altimeter Radio Science Experiment Ice Penetrating Radar Visible-Infrared Hyperspectral Imaging Spectrometer Ultraviolet Imaging Spectrograph Imaging System Magnetometer Particle Package Submillimetre Wave Instrument Radio and Plasma Wave Instrument Overall mission profile 06/2022 - Launch by Ariane-5 ECA + EVEE Cruise 01/2030 - Jupiter orbit insertion Jupiter tour Transfer to Callisto (11 months) Europa phase: 2 Europa and 3 Callisto flybys (1 month) Jupiter High Latitude Phase: 9 Callisto flybys (9 months) Transfer to Ganymede (11 months) 09/2032 – Ganymede orbit insertion Ganymede tour Elliptical and high altitude circular phases (5 months) Low altitude (500 km) circular orbit (4 months) 06/2033 – End of nominal mission Spacecraft 3-axis stabilised Power: solar panels: ~900 W HGA: ~3 m, body fixed X and Ka bands Downlink ≥ 1.4 Gbit/day High Δv capability (2700 m/s) Radiation tolerance: 50 krad at equipment level Dry mass: ~1800 kg Ground TM stations ESTRAC network Key mission drivers Radiation tolerance and technology Power budget and solar arrays challenges Mass budget Responsibilities ESA: manufacturing, launch, operations of the spacecraft and data archiving PI Teams: science payload provision, operations, and data analysis 3 Foreword The JUICE (JUpiter ICy moon Explorer) mission, selected by ESA in May 2012 to be the first large mission within the Cosmic Vision Program 2015–2025, will provide the most comprehensive exploration to date of the Jovian system in all its complexity, with particular emphasis on Ganymede as a planetary body and potential habitat. -
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. -
An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter
An Impacting Descent Probe for Europa and the other Galilean Moons of Jupiter P. Wurz1,*, D. Lasi1, N. Thomas1, D. Piazza1, A. Galli1, M. Jutzi1, S. Barabash2, M. Wieser2, W. Magnes3, H. Lammer3, U. Auster4, L.I. Gurvits5,6, and W. Hajdas7 1) Physikalisches Institut, University of Bern, Bern, Switzerland, 2) Swedish Institute of Space Physics, Kiruna, Sweden, 3) Space Research Institute, Austrian Academy of Sciences, Graz, Austria, 4) Institut f. Geophysik u. Extraterrestrische Physik, Technische Universität, Braunschweig, Germany, 5) Joint Institute for VLBI ERIC, Dwingelo, The Netherlands, 6) Department of Astrodynamics and Space Missions, Delft University of Technology, The Netherlands 7) Paul Scherrer Institute, Villigen, Switzerland. *) Corresponding author, [email protected], Tel.: +41 31 631 44 26, FAX: +41 31 631 44 05 1 Abstract We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (< 100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe’s fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. -
Mars, Phobos, and Deimos Sample Return Enabled by ARRM Alternative Trade Study Spacecraft
Mars, Phobos, and Deimos Sample Return Enabled by ARRM Alternative Trade Study Spacecraft Jacob A. Englander,∗ Matthew A. Vavrina,† Bo Naasz ,‡ Raymond G. Merill,MinQu§ ¶ The Asteroid Robotic Redirect Mission (ARRM) has been the topic of many mission design studies since 2011.1 The reference ARRM spacecraft uses a powerful solar electric propulsion (SEP) system and a bag device to capture a small asteroid from an Earth-like orbit and redirect it to a distant retrograde orbit (DRO) around the moon. The ARRM Option B spacecraft uses the same propulsion system and multi-Degree of Freedom (DoF) manipulators device to retrieve a very large sample (thousands of kilograms) from a 100+ meter diameter farther-away Near Earth Asteroid (NEA). This study will demonstrate that the ARRM Option B spacecraft design can also be used to return samples from Mars and its moons - either by acquiring a large rock from the surface of Phobos or Deimos, and/or by rendezvousing with a sample-return spacecraft launched from the surface of Mars. I. Introduction The Asteroid Robotic Redirect Mission (ARRM) Option A concept, first introduced in 2011,1 is a mission design to capture and return a small near-Earth asteroid (NEA) to cislunar space. The ARRM Option B concept is a similar spacecraft, but designed to return a very large sample from a more difficult to reach NEA.2 In this work we show that the spacecraft designed for ARRM Option B is also well-suited to sample return from Mars and its moons. This work presents low-thrust interplanetary trajectories from cislunar space to Mars and back, including descent from the Martian sphere of influence (SOI) to the desired orbit altitude and ascent to the SOI after the sample retrieval is complete. -
Deimos and Phobos As Destinations for Human Exploration
Deimos and Phobos as Destinations for Human Exploration Josh Hopkins Space Exploration Architect Lockheed Martin Caltech Space Challenge March 2013 © 2013 Lockheed Martin Corporation. All Rights Reserved 1 Topics • Related Lockheed Martin mission studies • Orbital mechanics vs solar cycles • Relevant characteristics of Phobos and Deimos • Locations to land • Considerations for designing your mission • Suggested trades 2 Stepping Stones Stepping Stones is a series of exploration 2023 missions building incrementally towards Deimos Scout the long term goal of exploring Mars. Each mission addresses science objectives relating to the formation of the solar 2031-2035 system and the origins of life. Red Rocks: explore Mars from Deimos 2024, 2025, 2029 2017 Plymouth Rock: Humans explore asteroids like Asteroid scout 1999 AO10 and 2000 SG344 2018-2023 Fastnet: Explore the Moon’s far side from Earth-Moon L2 region 2016 Asteroid survey 2017 SLS test flight 2013-2020 Human systems tests on ISS Lockheed Martin Notional Concept Dates subject to change 3 Deimos photo courtesy of NASA-JPL, University of Arizona Summary • A human mission to one of the two moons of Mars would be an easier precursor to a mission to land on Mars itself. • Astronauts would explore the moon in person and teleoperate rovers on the surface of Mars with minimal lag time, with the goal of returning samples to Earth. • “Red Rocks” mission to land on a Martian moon would follow “Plymouth Rock” missions to a Near Earth Asteroid. • Comparison of Deimos and Phobos revealed Deimos is the preferred destination for this mission. • We identified specific areas on Deimos and Phobos as optimal landing sites for an early mission focused on teleoperation. -
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. -