DOCSLIB.ORG

Design of a Multi-Moon Orbiter

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Design of a Multi-Moon Orbiter C A L T E C H ¢¡¤£¦¥§ ©¨ £¦ C Dynamical S Design of a Multi-Moon Orbiter Shane D. Ross Control and Dynamical Systems and JPL, Caltech W.S. Koon, M.W. Lo, J.E. Marsden AAS/AIAA Space Flight Mechanics Meeting Ponce, Puerto Rico February 9-13, 2003 Interplanetary Mission Design Use natural dynamics for fuel efficiency Dynamical channels connect planets and moons. Trajectory generation using invariant manifolds in the 3-body problem suggests new numerical algorithms for interplanetary missions Current research importance Design fuel efficient interplanetary trajectories (1) Multi-Moon Orbiter to multiple Jovian moons (2) Earth orbit to lunar orbit 2 Mission to Europa Motivation: Oceans and life on Europa? There is international interest in sending a scientific spacecraft to orbit and study Europa. 3 Multi-Moon Orbiter Orbit each moon in a single mission Other Jovian moons are also worthy of study • All may have oceans, evidence from Galileo suggests 5 Multi-Moon Orbiter We propose a trajectory design procedure which uses lit- tle fuel and allows a single spacecraft to orbit mul- tiple moons Orbit each moon for much longer than the quick flybys of previous missions Using a standard “patched-conics” approach, the ∆V necessary would be prohibitively high By decomposing the N-body problem into 3-body prob- lems and using the natural dynamics of the 3-body prob- lem, the ∆V can be lowered significantly 6 Multi-Moon Orbiter First attempt: A Ganymede-Europa Orbiter was constructed • ∆V of 1400 m/s was half the Hohmann transfer • G´omez,Koon, Lo, Marsden, Masdemont, and Ross [2001] Ganymede's orbit Maneuver Jupiter performed Europa's orbit z 1.5 1 0.5 0 1.5 y 1 -0. 5 0.5 0 -1 -0. 5 -1 x -1. 5 -1. 5 Injection into (a) high inclination Close approach orbit around Europa to Ganymede 0.02 0.01 0.015 0.01 0.005 0.005 0 z z 0 -0.005 -0.01 -0.005 -0.015 -0.02 -0.01 0.02 1.02 0.01 1.01 0.01 0.99 0.005 0 1 0.995 0 1 x -0.005 y y -0.01 0.99 1.005 x 1.01 -0.01 -0.02 0.98 (b) (c) 7 Multi-Moon Orbiter—Refinement • Preceding ∆V of 1400 m/s for the Ganymede-Europa or- biter was half the Hohmann transfer (that is, using patched conics, as in manned moon missions) • Desirable to decrease ∆V further—one now does not di- rectly “tube-hop”, but rather makes more refined use of the phase space structure • New things: resonant gravity assists with the moons • Interesting: still fits well with the tube-hopping method 32 Multi-Moon Orbiter Second attempt: Desirable to decrease ∆V further One can consider using resonant gravity assists with the moons, leading to ballistic captures Consider the following tour of Jupiter’s moons • Begin in an eccentric orbit with perijove at Callisto’s orbit, achievable using a patched-conics trajectory from the Earth to Jupiter • Orbit Callisto, Ganymede, and Europa 8 Multi-Moon Orbiter ∆V = 22 m/s, but flight time is a few years Low Energy Tour of Jupiter's Moons Seen in Jovicentric Inertial Frame Callisto Ganymede Europa Jupiter 9 Multi-Moon Orbiter Results are promising This result is preliminary • Model is a restricted bicircular 5-body problem • A user-assisted algorithm was necessary to produce it • An automated algorithm is a future goal Future challenges • The flight time is too long; should be reduced below 18 months • Evidence to be presented later in this talk suggests that a significant decrease in flight time can be gained for a modest increase in ∆V • Radiation dose is not accounted for; will be included in future models 10 Construction Procedure Building blocks Patched three-body model: linking two adjacent three-body systems Inter-moon transfer: decreasing Jovian energy via resonant gravity assists Orbiting each moon: ballistic capture and escape Small impulsive manuevers: to steer spacecraft in sensitive phase space We will give some background on these issues 11 Inter-Moon Transfer Spacecraft gets a gravity assist from outer moon M1 when it passes through apoapse if near a resonance When periapse close to inner moon M2’s orbit is reached, it takes “control”; this occurs for ellipse E Leaving moon M1 Approaching moon M2 Apoapse A fixed Periapse P fixed 15 Inter-Moon Transfer Small impulsive maneuvers are performed at opposition Exterior Realm Semimajor Axis vs. Time Forbidden Realm ∆a+ S/C J L1 M L2 Interior Realm ∆a- Spacecraft Maneuvers Performed When Opposite Moon ∆a- Moon Realm ∆a+ 16 Inter-Moon Transfer The transfer between three-body systems occurs when energy surfaces intersect; can be seen on semimajor axis vs. eccentricity diagram (similar to Tisserand curves of Longuski et al.) Spacecraft jumping between resonances on the way to Europa 0.3 Spacecraft path 0.25 0.2 0.15 eccentricity 0.1 Curves of Constant 0.05 3−Body Energy within each system 0 E G C 1 1.5 2 2.5 3 3.5 4 semimajor axis (a = 1) Europa 17 Ballistic Capture An L2 orbit manifold tube leading to ballistic capture around a moon is shown schematically Escape is the time reverse of ballistic capture 18 Why Does It Work? Recall the planar circular restricted three-body problem: motion of a spacecraft in the gravitational field of two larger bodies in circular motion. • View in rotating frame =⇒ constant energy E Forbidden Realm (at a particular energy level) Exterior Realm L1 L2 Poincare section Interior (Jupiter) Realm spacecraft Moon Realm Rotating frame: different realms of motion at energy E. 19 Poincar´eSurface of Section Study Poincar´esurface of section at fixed energy E, reducing system to a 2-dimensional area preserving map. z P(z) Poincar´esurface of section 20 Poincar´eSurface of Section Poincar´esection reveals mixed phase space structure: KAM tori and a “chaotic sea” are visible. Identify ) 1 = ne u t p e N s ( i x or A j ma i m e S Argument of Periapse (radians) Poincar´esurface of section 21 Transport in Poincar´eSection Phase space divided into regions Ri, i = 1, ..., NR bounded by segments of stable and unstable manifolds of unstable fixed points. p1 R2 q4 q1 R3 q2 R1 q3 B12 = U [p2 ,q2] U S [p1 ,q2] p2 q5 p3 R4 R5 q6 22 Lobe Dynamics Transport btwn regions computed via lobe dynamics. L2,1(1) R2 q0 f (L1,2(1)) q1 -1 f (q0) L1,2(1) pj pi f (L2,1(1)) R1 23 Movement btwn Resonances We can compute manifolds which naturally divide the phase space into resonance regions. Identify s i x or A j ma i m e S Argument of Periapse Unstable and stable manifolds in red and green, resp. 24 Movement btwn Resonances Transport and mixing between regions can be computed. Identify R3 s i x or A j R2 ma i m e S R1 Argument of Periapse Four sequences of color coded lobes are shown. 25 Movement btwn Resonances Navigation from one resonance to another, essential for the Multi-Moon Orbiter, can be performed. Identify Resonance R Region B 3 is x } A r o j a m i R 2 m e S } Resonance R Region A } 1 Argument of Periapse 26 Resonances and Tubes Resonances and tubes are linked It has been observed that the tubes of capture (resp., escape) orbits are coming from (resp., going to) cer- tain resonances. Resonances are a function of energy E and the mass parameter µ Koon, Lo, Marsden, Ross [2001] 27 Earth to Moon Trajectories Similar methods can be applied to near-Earth space to study the ∆V verses time trade-off 68 Earth to Moon Trajectories Results: much shorter transfer times than previous authors for only slightly more ∆V Trajectories from a circular Earth orbit (r=59669 km) to a stable lunar orbit 1300 Hohmann transfer ∆V = 1220 m/s 1200 TOF = 6.6 days 1100 1000 V (m/s) ∆ 900 Present Work 800 Bollt & Meiss [1995] Schroer & Ott [1997] 700 0 100 200 300 400 500 600 700 800 Time of Flight (days) 39 Earth to Moon Trajectories Compare with Bollt and Meiss [1995] • A tenth of the time for only 100 m/s more Current Result Bollt and Meiss [1995] 65 days, ∆V = 860 m/s 748 days, ∆V = 750 m/s TOF = 65 days ∆V = 860 m/s 1 Day Tick Marks Earth Moon 40 e.g., GEO to Lunar Orbit GEO to Moon Orbit Transfer Seen in Geocentric Inertial Frame TOF = 63 days ∆V = 1211 m/s 1 Day Tick Marks Moon's Earth Orbit 41 References • Trade-Off Between Fuel and Time Optimization, in preparation. • Koon, W.S., M.W. Lo, J.E. Marsden and S.D. Ross [2002] Constructing a low energy transfer between Jovian moons. Contemporary Mathematics 292, 129–145. • G´omez,G., W.S. Koon, M.W. Lo, J.E. Marsden, J. Masdemont and S.D. Ross [2001] Invariant manifolds, the spatial three-body problem and space mission design. AAS/AIAA Astrodynamics Specialist Conference. • Koon, W.S., M.W. Lo, J.E. Marsden & S.D. Ross [2001] Resonance and capture of Jupiter comets. Celestial Mechanics & Dynamical Astronomy 81(1-2), 27–38. • Koon, W.S., M.W. Lo, J.E. Marsden and S.D. Ross [2000] Heteroclinic con- nections between periodic orbits and resonance transitions in celes- tial mechanics. Chaos 10(2), 427–469. For papers, movies, etc., visit the websites: http://www.cds.caltech.edu/∼marsden http://www.cds.caltech.edu/∼shane 27.
Load more

Recommended publications
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • Predictable Patterns in Planetary Transit Timing Variations and Transit Duration Variations Due to Exomoons
    Astronomy & Astrophysics manuscript no. ms c ESO 2016 June 21, 2016 Predictable patterns in planetary transit timing variations and transit duration variations due to exomoons René Heller1, Michael Hippke2, Ben Placek3, Daniel Angerhausen4, 5, and Eric Agol6, 7 1 Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany; [email protected] 2 Luiter Straße 21b, 47506 Neukirchen-Vluyn, Germany; [email protected] 3 Center for Science and Technology, Schenectady County Community College, Schenectady, NY 12305, USA; [email protected] 4 NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; [email protected] 5 USRA NASA Postdoctoral Program Fellow, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA 6 Astronomy Department, University of Washington, Seattle, WA 98195, USA; [email protected] 7 NASA Astrobiology Institute’s Virtual Planetary Laboratory, Seattle, WA 98195, USA Received 22 March 2016; Accepted 12 April 2016 ABSTRACT We present new ways to identify single and multiple moons around extrasolar planets using planetary transit timing variations (TTVs) and transit duration variations (TDVs). For planets with one moon, measurements from successive transits exhibit a hitherto unde- scribed pattern in the TTV-TDV diagram, originating from the stroboscopic sampling of the planet’s orbit around the planet–moon barycenter. This pattern is fully determined and analytically predictable after three consecutive transits. The more measurements become available, the more the TTV-TDV diagram approaches an ellipse. For planets with multi-moons in orbital mean motion reso- nance (MMR), like the Galilean moon system, the pattern is much more complex and addressed numerically in this report.
    [Show full text]
  • Abstracts of the 50Th DDA Meeting (Boulder, CO)
    Abstracts of the 50th DDA Meeting (Boulder, CO) American Astronomical Society June, 2019 100 — Dynamics on Asteroids break-up event around a Lagrange point. 100.01 — Simulations of a Synthetic Eurybates 100.02 — High-Fidelity Testing of Binary Asteroid Collisional Family Formation with Applications to 1999 KW4 Timothy Holt1; David Nesvorny2; Jonathan Horner1; Alex B. Davis1; Daniel Scheeres1 Rachel King1; Brad Carter1; Leigh Brookshaw1 1 Aerospace Engineering Sciences, University of Colorado Boulder 1 Centre for Astrophysics, University of Southern Queensland (Boulder, Colorado, United States) (Longmont, Colorado, United States) 2 Southwest Research Institute (Boulder, Connecticut, United The commonly accepted formation process for asym- States) metric binary asteroids is the spin up and eventual fission of rubble pile asteroids as proposed by Walsh, Of the six recognized collisional families in the Jo- Richardson and Michel (Walsh et al., Nature 2008) vian Trojan swarms, the Eurybates family is the and Scheeres (Scheeres, Icarus 2007). In this theory largest, with over 200 recognized members. Located a rubble pile asteroid is spun up by YORP until it around the Jovian L4 Lagrange point, librations of reaches a critical spin rate and experiences a mass the members make this family an interesting study shedding event forming a close, low-eccentricity in orbital dynamics. The Jovian Trojans are thought satellite. Further work by Jacobson and Scheeres to have been captured during an early period of in- used a planar, two-ellipsoid model to analyze the stability in the Solar system. The parent body of the evolutionary pathways of such a formation event family, 3548 Eurybates is one of the targets for the from the moment the bodies initially fission (Jacob- LUCY spacecraft, and our work will provide a dy- son and Scheeres, Icarus 2011).
    [Show full text]
  • The Asteroid Florence 3122
    The Asteroid Florence 3122 By Mohammad Hassan BACKGROUND • Asteroid 3122 Florence is a stony trinary asteroid of the Amor group. • It was discovered on March 2nd 1981 by Astronomer Schelte J. ”Bobby” Bus at Siding Spring Observatory. It was named in honor of Florence Nightingdale, the founder of modern nursing. • It has an approximate diameter of 5 kilometers. It also orbits the Sun at a distance of 1.0-2.5 astronomical unit once every 2 years and 4 months (859 days). • Florence rotates once every 2.4 hours, a result that was determined previously from optical measurements of the asteroid’s brightness variations. • THE MOST FASINATING THING IS THAT IT HAS TWO MOONS, HENCE WHY IT IS A PART OF THE AMOR GROUP. • The reason why this Asteroid 3122 Florence is important is because it is a near-earth object with the potential of hitting the earth in the future time. Concerns? • Florence 3122 was classified as a potentially hazardous object because of its minimum orbit intersection distance (less than 0.05 AU). This means that Florence 3122 has the potential to make close approaches to the Earth. • Another thing to keep in mind was that Florence 3122 minimum distance from us was 7 millions of km, about 20 times farthest than our moon. What actually happened? • On September 1st, 2017, Florence passed 0.047237 AU from Earth. That is about 7,000 km or 4,400 miles. • From Earth’s perspective, it brightened to apparent magnitude 8.5. It was also visible in small telescopes for several nights as it moved from south to north through the constellations.
    [Show full text]
  • Exploration of the Planets – 1971
    Video Transcript for Archival Research Catalog (ARC) Identifier 649404 Exploration of the Planets – 1971 Narrator: For thousands of years, man observed the rising and setting Sun, the cycle of seasons, the fixed stars, and those he called wanderers, or planets. And from these observations evolved his notions of the universe. The naked eye extended its vision through instruments that saw the craters on the Moon, the changing colors of Mars, and the rings of Saturn. The fantasies, dreams, and visions of space travel became the reality of Apollo. Early in 1970, President Nixon announced the objectives of a balanced space program for the United States that would include the scientific investigation of all the planets in the solar system. Of the nine planets circling the Sun, only the Earth is known to us at firsthand. But observational techniques on Earth and in space have given us some idea of the appearance and movement of the planets. And enable us to depict their physical characteristics in some detail. Mercury, only slightly larger than the Moon, is so close to the Sun that it is difficult to observe by telescope. It is believed to be one large cinder, with no atmosphere and a day-night temperature range of nearly 1,000 degrees. Venus is perpetually cloud-covered. Spacecraft report a surface temperature of 900 degrees Fahrenheit and an atmospheric pressure 100 times greater than Earth’s. We can only guess what the surface is like, possibly a seething netherworld beneath a crushing, poisonous carbon dioxide atmosphere. Of Mars, the Red Planet, we have evidence of its cratered surface, photographed by the Mariner spacecraft.
    [Show full text]
  • Low Velocity Impacts Mars's Inner Moon, Phobos, Is Located Deep In
    Phobos: Low Velocity Impacts Mars’s inner moon, Phobos, is located deep in the planet’s gravity well and orbits far below the planet’s synchronous orbit. Images of the surface of Phobos, in particular from Viking Orbiter 1, MGS, MRO, and MEX, reveal a rich collisional history, including fresh‐looking impact craters and subdued older ones, very large impact structures (compared to the size of Phobos), such as Stickney, and much smaller ones. Sources of impactors colliding with Phobos include a priori: A) Impactors from outside the martian system (asteroids, comets, and fragments thereof); B) Impactors from Mars itself (ejecta from large impacts on Mars); and C) Impactors from Mars orbit, including impact ejecta launched from Deimos and ejecta launched from, and reintercepted by, Phobos. In addition to individual craters on Phobos, the networks of grooves on this moon have also been attributed in part or in whole to impactors from some of these sources, particularly B. We report the preliminary results of a systematic survey of the distribution, morphology, albedo, and color characteristics of fresh impact craters and associated ejecta deposits on Phobos. Considering that the different potential impactor sources listed above are expected to display distinct dominant compositions and different characteristic impact velocity regimes, we identify specific craters on Phobos that are more likely the result of low velocity impacts by impactors derived from Mars orbit than from any alternative sources. Our finding supports the hypothesis that the spectrally “Redder Unit” on Phobos may be a superficial veneer of accreted ejecta from Deimos, and that Phobos’s bulk might be distinct in composition from Deimos.
    [Show full text]
  • Possibilities for Life in the Inner Solar System We Will Now Begin Going
    Possibilities for Life in the Inner Solar System We will now begin going systematically through other possible locations for life (not necessarily intelligent life) in the Solar System. Some possibilities are obvious: Mars and Jupiter’s moon Europa are examples. However, in the interest of continuing open-mindedness, in this lecture we will discuss our Moon, Mercury, the moons of Mars, and Venus. Next lec- ture will focus on Mars, which has a real possibility of having had life at one point, or even having it now below the surface. As we discuss each object, we will keep in mind our basic requirements for life: chemical building blocks, liquids in some place, energy, and stability. Our Moon The Moon is the closest astronomical object to the Earth, and the only one on which we can see significant surface features with our naked eyes (the Sun is too bright, and everything else is pointlike or, like the Andromeda galaxy, too dim). As a result, it has from time immemorial inspired many fanciful notions, including that the Moon is inhabited. In fact, life on the Moon was the subject of one of the most famous hoaxes ever perpetrated. On August 25, 1835 the New York Sun, a small newspaper with a daily circulation of about 4,000, printed a remarkable story on page 2. According to them Sir John Herschel (son of the discoverer of Uranus) had been observing the Moon with a new telescope based in South Africa. The results were astounding. He had seen herds of bison, many beavers, a rich variety of plants, and, most intriguingly, traces of artificial features with smoke coming out of them.
    [Show full text]
  • Martian Moon's Orbit Hints at an Ancient Ring of Mars
    Martian Moon’s Orbit Hints at an Ancient Ring of Mars PRESS RELEASE DATE June 2, 2020 CONTACT Rebecca McDonald Director of Communications SETI Institute [email protected] +1 650-960-4526 Photo credit: https://solarsystem.nasa.gov/moons/mars-moons/deimos/in-depth/ June 2, 2020, Mountain View, CA – Scientists from the SETI Institute and Purdue University have found that the only way to produce Deimos’s unusually tilted orbit is for Mars to have had a ring billions of years ago. While some of the more massive planets in our solar system have giant rings and numerous big moons, Mars only has two small, misshapen moons, Phobos and Deimos. Although these moons are small, their peculiar orbits hide important secrets about their past. For a long time, scientists believed that Mars’s two moons, discovered in 1877, were captured asteroids. However, since their orbits are almost in the same plane as Mars’s equator, that the moons must have formed at the same time as Mars. But the orbit of the smaller, more distant moon Deimos is tilted by two degrees. “The fact that Deimos’s orbit is not exactly in plane with Mars’s equator was considered unimportant, and nobody cared to try to explain it,” says lead author Matija Ćuk, a research scientist at the SETI Institute. “But once we had a big new idea and we looked at it with new eyes, Deimos’s orbital tilt revealed its big secret.” This significant new idea was put forward in 2017 byĆ uk’s co-author David Minton, professor at Purdue University and his then-graduate student Andrew Hesselbrock.
    [Show full text]
  • Accretion of Saturn's Mid-Sized Moons During the Viscous
    Accretion of Saturn’s mid-sized moons during the viscous spreading of young massive rings: solving the paradox of silicate-poor rings versus silicate-rich moons. Sébastien CHARNOZ *,1 Aurélien CRIDA 2 Julie C. CASTILLO-ROGEZ 3 Valery LAINEY 4 Luke DONES 5 Özgür KARATEKIN 6 Gabriel TOBIE 7 Stephane MATHIS 1 Christophe LE PONCIN-LAFITTE 8 Julien SALMON 5,1 (1) Laboratoire AIM, UMR 7158, Université Paris Diderot /CEA IRFU /CNRS, Centre de l’Orme les Merisiers, 91191, Gif sur Yvette Cedex France (2) Université de Nice Sophia-antipolis / C.N.R.S. / Observatoire de la Côte d'Azur Laboratoire Cassiopée UMR6202, BP4229, 06304 NICE cedex 4, France (3) Jet Propulsion Laboratory, California Institute of Technology, M/S 79-24, 4800 Oak Drive Pasadena, CA 91109 USA (4) IMCCE, Observatoire de Paris, UMR 8028 CNRS / UPMC, 77 Av. Denfert-Rochereau, 75014, Paris, France (5) Department of Space Studies, Southwest Research Institute, Boulder, Colorado 80302, USA (6) Royal Observatory of Belgium, Avenue Circulaire 3, 1180 Uccle, Bruxelles, Belgium (7) Université de Nantes, UFR des Sciences et des Techniques, Laboratoire de Planétologie et Géodynamique, 2 rue de la Houssinière, B.P. 92208, 44322 Nantes Cedex 3, France (8) SyRTE, Observatoire de Paris, UMR 8630 du CNRS, 77 Av. Denfert-Rochereau, 75014, Paris, France (*) To whom correspondence should be addressed ([email protected]) 1 ABSTRACT The origin of Saturn’s inner mid-sized moons (Mimas, Enceladus, Tethys, Dione and Rhea) and Saturn’s rings is debated. Charnoz et al. (2010) introduced the idea that the smallest inner moons could form from the spreading of the rings’ edge while Salmon et al.
    [Show full text]
  • Evolution of a Terrestrial Multiple Moon System
    THE ASTRONOMICAL JOURNAL, 117:603È620, 1999 January ( 1999. The American Astronomical Society. All rights reserved. Printed in U.S.A. EVOLUTION OF A TERRESTRIAL MULTIPLE-MOON SYSTEM ROBIN M. CANUP AND HAROLD F. LEVISON Southwest Research Institute, 1050 Walnut Street, Suite 426, Boulder, CO 80302 AND GLEN R. STEWART Laboratory for Atmospheric and Space Physics, University of Colorado, Campus Box 392, Boulder, CO 80309-0392 Received 1998 March 30; accepted 1998 September 29 ABSTRACT The currently favored theory of lunar origin is the giant-impact hypothesis. Recent work that has modeled accretional growth in impact-generated disks has found that systems with one or two large moons and external debris are common outcomes. In this paper we investigate the evolution of terres- trial multiple-moon systems as they evolve due to mutual interactions (including mean motion resonances) and tidal interaction with Earth, using both analytical techniques and numerical integra- tions. We Ðnd that multiple-moon conÐgurations that form from impact-generated disks are typically unstable: these systems will likely evolve into a single-moon state as the moons mutually collide or as the inner moonlet crashes into Earth. Key words: Moon È planets and satellites: general È solar system: formation INTRODUCTION 1. 1000 orbits). This result was relatively independent of initial The ““ giant-impact ÏÏ scenario proposes that the impact of disk conditions and collisional parameterizations. Pertur- a Mars-sized body with early Earth ejects enough material bations by the largest moonlet(s) were very e†ective at clear- into EarthÏs orbit to form the Moon (Hartmann & Davis ing out inner disk materialÈin all of the ICS97 simulations, 1975; Cameron & Ward 1976).
    [Show full text]
  • The Formation of the Martian Moons Rosenblatt P., Hyodo R
    The Final Manuscript to Oxford Science Encyclopedia: The formation of the Martian moons Rosenblatt P., Hyodo R., Pignatale F., Trinh A., Charnoz S., Dunseath K.M., Dunseath-Terao M., & Genda H. Summary Almost all the planets of our solar system have moons. Each planetary system has however unique characteristics. The Martian system has not one single big moon like the Earth, not tens of moons of various sizes like for the giant planets, but two small moons: Phobos and Deimos. How did form such a system? This question is still being investigated on the basis of the Earth-based and space-borne observations of the Martian moons and of the more modern theories proposed to account for the formation of other moon systems. The most recent scenario of formation of the Martian moons relies on a giant impact occurring at early Mars history and having also formed the so-called hemispheric crustal dichotomy. This scenario accounts for the current orbits of both moons unlike the scenario of capture of small size asteroids. It also predicts a composition of disk material as a mixture of Mars and impactor materials that is in agreement with remote sensing observations of both moon surfaces, which suggests a composition different from Mars. The composition of the Martian moons is however unclear, given the ambiguity on the interpretation of the remote sensing observations. The study of the formation of the Martian moon system has improved our understanding of moon formation of terrestrial planets: The giant collision scenario can have various outcomes and not only a big moon as for the Earth.
    [Show full text]