Résumé: Daniel R. Adamo Mailing Address
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Discovery of Earth's Quasi-Satellite
Meteoritics & Planetary Science 39, Nr 8, 1251–1255 (2004) Abstract available online at http://meteoritics.org Discovery of Earth’s quasi-satellite Martin CONNORS,1* Christian VEILLET,2 Ramon BRASSER,3 Paul WIEGERT,4 Paul CHODAS,5 Seppo MIKKOLA,6 and Kimmo INNANEN3 1Athabasca University, Athabasca AB, Canada T9S 3A3 2Canada-France-Hawaii Telescope, P. O. Box 1597, Kamuela, Hawaii 96743, USA 3Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 Canada 4Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7, Canada 5Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109, USA 6Turku University Observatory, Tuorla, FIN-21500 Piikkiö, Finland *Corresponding author. E-mail: [email protected] (Received 18 February 2004; revision accepted 12 July 2004) Abstract–The newly discovered asteroid 2003 YN107 is currently a quasi-satellite of the Earth, making a satellite-like orbit of high inclination with apparent period of one year. The term quasi- satellite is used since these large orbits are not completely closed, but rather perturbed portions of the asteroid’s orbit around the Sun. Due to its extremely Earth-like orbit, this asteroid is influenced by Earth’s gravity to remain within 0.1 AU of the Earth for approximately 10 years (1997 to 2006). Prior to this, it had been on a horseshoe orbit closely following Earth’s orbit for several hundred years. It will re-enter such an orbit, and make one final libration of 123 years, after which it will have a close interaction with the Earth and transition to a circulating orbit. -
Origin and Evolution of Trojan Asteroids 725
Marzari et al.: Origin and Evolution of Trojan Asteroids 725 Origin and Evolution of Trojan Asteroids F. Marzari University of Padova, Italy H. Scholl Observatoire de Nice, France C. Murray University of London, England C. Lagerkvist Uppsala Astronomical Observatory, Sweden The regions around the L4 and L5 Lagrangian points of Jupiter are populated by two large swarms of asteroids called the Trojans. They may be as numerous as the main-belt asteroids and their dynamics is peculiar, involving a 1:1 resonance with Jupiter. Their origin probably dates back to the formation of Jupiter: the Trojan precursors were planetesimals orbiting close to the growing planet. Different mechanisms, including the mass growth of Jupiter, collisional diffusion, and gas drag friction, contributed to the capture of planetesimals in stable Trojan orbits before the final dispersal. The subsequent evolution of Trojan asteroids is the outcome of the joint action of different physical processes involving dynamical diffusion and excitation and collisional evolution. As a result, the present population is possibly different in both orbital and size distribution from the primordial one. No other significant population of Trojan aster- oids have been found so far around other planets, apart from six Trojans of Mars, whose origin and evolution are probably very different from the Trojans of Jupiter. 1. INTRODUCTION originate from the collisional disruption and subsequent reaccumulation of larger primordial bodies. As of May 2001, about 1000 asteroids had been classi- A basic understanding of why asteroids can cluster in fied as Jupiter Trojans (http://cfa-www.harvard.edu/cfa/ps/ the orbit of Jupiter was developed more than a century lists/JupiterTrojans.html), some of which had only been ob- before the first Trojan asteroid was discovered. -
Horsing Around on Saturn
Horsing Around on Saturn Robert J. Vanderbei Operations Research and Financial Engineering, Princeton University [email protected] ABSTRACT Based on simple statistical mechanical models, the prevailing view of Sat- urn’s rings is that they are unstable and must therefore have been formed rather recently. In this paper, we argue that Saturn’s rings and inner moons are in much more stable orbits than previously thought and therefore that they likely formed together as part of the initial formation of the solar system. To make this argument, we give a detailed description of so-called horseshoe orbits and show that this horseshoeing phenomenon greatly stabilizes the rings of Saturn. This paper is part of a collaborative effort with E. Belbruno and J.R. Gott III. For a description of their part of the work, see their papers in these proceedings. 1. Introduction The currently accepted view (see, e.g., Goldreich and Tremaine (1982)) of the formation of Saturn’s rings is that a moon-sized object wandered inside Saturn’s Roche limit and was torn apart by tidal forces. The resulting array of remnant masses was dispersed and formed the rings we see today. In this model, the system dynamics are treated as a turbulent flow with no explicit mention of the law of gravitation. The ring shape is presumed to be maintained by the coralling effect of a few of the inner moons acting as so-called shepherds. Of course, a simpler explanation would be that the rings formed along with the planets and their moons as they condensed out of the solar nebula. -
Russian Networks Capable to Observe Neos at Near Space
52-th Session of STSC UN COPUOS Vienna, Austria, February 3, 2015 The NEO problem: current activities in Russia V.Emel’yanenko Basic aspects of the NEO problem Major constituents of the NEO (Asteroid/Comet Impact Hazard - ACH) problem are: Detection and characterization Risk assessment Protection and mitigation We work in all areas at both national and international levels. 2 General activities (Feb 2014 – Feb 2015) Studies of the Chelyabinsk meteorite; Completion of the 1.6 m telescope for NEO detection; Work on the development of a moderate aperture telescope national network aimed to detection and monitoring of NEOs; Various projects of space based means to detect and to counteract dangerous bodies; Construction of a data-bank on impact consequences . 3 Some lessons of the Chelyabinsk event (15 Feb, 2013): Asteroids of decameter size could be very dangerous; We need to know about coming threat reasonably in advance; Day time asteroids are unobservable by any ground based facilities. 4 En route to the NEO detection AZT-33IR AZT-33VM The telescope АZТ-33VM ( ∅ 1.6 m) for the mass detection of NEOs at large distances is nearing completion. First light is expected in the fall of 2015. 5 ISON telescopes for NEO surveys and follow- up observations ISON (International Scientific Optical Network) – one of the largest Russian networks capable to observe NEOs at near space. 6 ISON : results on asteroids Hundreds of light curves were constructed for tens of NEAs (3122) Florence, (20187) Janapittichova, (25916) 2001 CP44, (162004) 1991 VE, (7888) -
Arxiv:1304.1048V2 [Astro-Ph.EP] 26 Apr 2013 and Murray (1981A), General Properties of the Tadpole and Horseshoe Orbits Are Described in the Quasi- Circular Case
On the co-orbital motion of two planets in quasi-circular orbits Philippe Robutel and Alexandre Pousse IMCCE, Observatoire de Paris, UPMC, CNRS UMR8028, 77 Av. Denfert-Rochereau, 75014 Paris, France August 27, 2018 ABSTRACT We develop an analytical Hamiltonian formalism adapted to the study of the motion of two planets in co-orbital resonance. The Hamiltonian, averaged over one of the planetary mean lon- gitude, is expanded in power series of eccentricities and inclinations. The model, which is valid in the entire co-orbital region, possesses an integrable approximation modeling the planar and quasi-circular motions. First, focusing on the fixed points of this approximation, we highlight re- lations linking the eigenvectors of the associated linearized differential system and the existence of certain remarkable orbits like the elliptic Eulerian Lagrangian configurations, the Anti-Lagrange (Giuppone et al., 2010) orbits and some second sort orbits discovered by Poincar´e. Then, the variational equation is studied in the vicinity of any quasi-circular periodic solution. The funda- mental frequencies of the trajectory are deduced and possible occurrence of low order resonances are discussed. Finally, with the help of the construction of a Birkhoff normal form, we prove that the elliptic Lagrangian equilateral configurations and the Anti-Lagrange orbits bifurcate from the same fixed point L4. Subject headings: Co-orbitals; Resonance; Lagrange; Euler; Planetary problem; Three-body prob- lem 1. Introduction The co-orbital resonance has been extensively studied for more than one hundred years in the framework of the restricted three-body problem (RTBP). In most of the analytical works, the emphasis has been placed on the tadpole orbits, trajectories surrounding one of the two Lagrangian triangular equilibrium points, since these describe the motion of the Jovian Trojans. -
Hered in These Proceedings with the Aim to Keep Track of These Very Interesting Days
Proceedings of GAIA-FUN-SSO 2014 Third “Gaia Follow-up Network for Solar System Objects” Workshop held at IMCCE/Paris Observatory 2014, November 24 – 26 Institut de mécanique céleste et de calcul des éphémérides Observatoire de Paris Legal Deposite – June 2015 ISBN 2-910015-73-4 Foreword The observation of Solar System Objects (SSO) by the Gaia space astrometry mission will be constrained by a scanning law. Much detection of interesting objects may occur with no possibility of further observations by the probe. These objects will then require complementary ground-based observations. Among them, previously unknown Near- Earth Objects, fast moving towards the Earth or going away from it could be found. Several objects discovered by Gaia could also be Inner-Earth Objects, as the probe will observe at rather low Solar elongations. In order to confirm from the ground the discoveries made in space and to follow interesting targets, a dedicated network is organized, the Gaia Follow-Up Network. This task is performed in the frame of the Coordination Unit 4 of the Gaia Data Processing and Analysis Consortium (DPAC), devoted to data processing of specific objects. The goal of the network is to improve the knowledge of the orbit of poorly observed targets by astrometric observations on alert. This activity is coordinated by a central node interacting with the Gaia data reduction pipeline all along the mission. In 2010 and 2012, we had organized the first two workshops in order to initiate the network and to meet the participants. In 2014, almost one year after the launch of Gaia, we organize the third Gaia-FUN-SSO workshop in Paris in order to discuss further the coordination of the network of observing stations, to discuss the prelaunch training observations which have been performed and to prepare the network for the operating phase of the alert mode which must begin in 2015. -
Arxiv:1901.07250V1
Astronomy & Astrophysics manuscript no. coorb_trans_arXiv c ESO 2019 January 23, 2019 Co-orbital exoplanets from close period candidates: The TOI-178 case A. Leleu1???, J. Lillo-Box2, M. Sestovic3, P. Robutel4, A. C. M. Correia5;4, N. Hara6??, D. Angerhausen3;7, S. L. Grimm3, J. Schneider8 1 Physikalisches Institut, Universität Bern, Gesellschaftsstr. 6, 3012 Bern, Switzerland. 2 European Southern Observatory, Alonso de Cordova 3107, Vitacura Casilla 19001, Santiago 19, Chile. 3 Center for Space and Habitability, University of Bern, Gesellschaftsstr. 6, 3012 Bern, Switzerland. 4 IMCCE, Observatoire de Paris - PSL Research University, UPMC Univ. Paris 06, Univ. Lille 1, CNRS, 77 Avenue Denfert-Rochereau, 75014 Paris, France. 5 CFisUC, Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal. 6 Observatoire de Genève, Université de Genève, 51 ch. des Maillettes, 1290 Versoix, Switzerland. 7 Blue Marble Space Institute of Science, 1001 4th Ave Suite 3201, Seattle, WA 98154, USA. 8 Paris Observatory, LUTh UMR 8102, 92190 Meudon,France. January 23, 2019 ABSTRACT Despite the existence of co-orbital bodies in the solar system, and the prediction of the formation of co-orbital planets by planetary system formation models, no co-orbital exoplanets (also called trojans) have been detected thus far. Here we study the signature of co-orbital exoplanets in transit surveys when two planet candidates in the system orbit the star with similar periods. Such pair of candidates could be discarded as false positives because they are not Hill-stable. However, horseshoe or long libration period tadpole co-orbital configurations can explain such period similarity. This degeneracy can be solved by considering the Transit Timing Variations (TTVs) of each planet. -
The “Horseshoe” Orbit of Near-Earth Object 2013 BS45 DANIEL R
Page 20 Astrodynamics The “Horseshoe” Orbit of Near-Earth Object 2013 BS45 DANIEL R. ADAMO, ASTRODYNAMICS CONSULTANT 1. Earth-Based Discovery million km) on 12 February inbound towards the Sun. It 2013. reaches perihelion on 29 April Discovered by the Space- 2013 at 0.92 AU or 92% of watch 1.8 m telescope (see As is typical among NEO Earth’s mean distance from Figure 1) on 20 January 2013, discoveries made in the night the Sun. Figure 2 is a plot of near-Earth object (NEO) 2013 sky prior to closest Earth ap- 2013 BS45, Earth, and Mars as BS45 closely encountered proach with observations of they orbit the Sun during Earth at a range of 0.0126 AU our planet’s night sky, 2013 2013. (4.9 lunar distances or 1.88 BS45 crosses Earth’s orbit Figure 1. The 1.8 m Space- watch telescope is pictured inside its protective dome at Kitt Peak, Arizona (photograph by Robert S. McMillan). Figure 2. Orbits of 2013 BS45 (blue), Earth (green), and Mars (red) are plotted during year 2013 in a non-rotating (inertial) Sun-centered (heliocentric) coordinate system. The plot plane coincides with that of Earth’s orbit, the ecliptic, and 2013 BS45’s orbit is inclined to the ecliptic by less than 1°. Before moving into Earth’s BS45 ephemerides with maxi- planetary radar observations daytime sky circa 9 February mum position uncertainties conducted at Goldstone, CA 2013, about 80 optical obser- equivalent to hundreds of had reduced this uncertainty vations were being processed minutes in heliocentric mo- to the order of 10 minutes. -
Preliminary Lander Cubesat Design for Small Asteroid Detumbling Mission
DEGREE PROJECT IN VEHICLE ENGINEERING, SECOND CYCLE, 30 CREDITS STOCKHOLM, SWEDEN 2018 Preliminary Lander CubeSat Design for Small Asteroid Detumbling Mission AGNE PASKEVICIUTE KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ENGINEERING SCIENCES Preliminary Lander CubeSat Design for Small Asteroid Detumbling Mission AgnėPaökevičiūtė Department of Aeronautical and Vehicle Engineering KTH Royal Institute of Technology This thesis is submitted for the degree of Master of Science October 2018 Skiriu ö˛ darbπsavo mamai Graûinai ir tėčiui Algirdui. Acknowledgements This thesis would have not been possible without the encouragement and support of numerous people in my life. I would especially like to thank Dr Michael C. F. Bazzocchi for his support and constructive advice throughout my research. In addition, I would like to express my gratitude to researchers, professors and staffat Luleå University of Technology, Space Campus, for their ideas and help in practical matters. I would like to sincerely thank my family, boyfriend, and friends for believing in me, encour- aging me to reach for my dreams, and loving me without any expectations. Last but not least, I am truly grateful for the opportunities KTH Royal Institute of Technol- ogy provided. Sammanfattning Gruvdrift på asteroider förväntas att bli verklighet inom en snar framtid. Det första steget är att omdirigera en asteroid till en stabil omloppsbana runt jorden så att gruvteknik kan demon- streras. Bromsning av asteroidens tumlande är en av de viktigaste stegen i ett rymduppdrag där en asteroid ska omdirigeras. I detta examensarbete föreslås en preliminär asteroidlandare baserad på CubeSat-teknik för ett rymduppdrag där en asteroid ska omdirigeras. En asteroid av Arjuna-typ, 2014 UR, med en diameter på mellan 10.6 och 21.2 m är vald som kandidat för rymduppdraget. -
Astrometry of Three Near Earth Asteroids with the Lijiang 2.4 M Telescope
Research in Astron. Astrophys. Vol.xx (20xx) No.XX, 000–000 Research in http://www.raa-journal.org http://www.iop.org/journals/raa Astronomy and Astrophysics Astrometry of three near Earth asteroids with the Lijiang 2.4 m telescope Xi-Liang Zhang1;2;3, Yong Yu3, Xue-Li Wang1;2, Chuan-Jun Wang1;2, Liang Chang1;2 Yu-Feng Fan1;2 and Zheng-Hong Tang3 1 Yunnan Observatories, Chinese Academy of Sciences (CAS), P. O. Box 110, Kunming 650011, China; [email protected] 2 Key Laboratory of the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, P. O. Box 110, Kunming 650011, China 3 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 20030, China Received 2014 April 10; accepted 2014 June 27 Abstract Under the framework of the observational campaigns organized by the GAIA Follow Up Network for Solar System Objects (GAIA-FUN-SSO), three near Earth asteroids of (367943) Duende, (99942) Apophis and 2013 TV135 were observed with the Lijiang 2.4 m telescope of Yunnan Observatories. The software PRISM was used to calibrate the CCD fields and measure the positions of Apophis and 2013 TV135, and our own software was used to Duende. Comparison results have shown that, the ephemerides of INPOP10a and JPL are consistent for Apophis and 2013 TV135, however quite inconsistent for Duende. Moreover, we have found that the mean values of the system errors between the ephemerides of INPOP10a and JPL are about 7200 and ¡19900 in right ascension and declination respectively for Duende, and the ephemeris JPL is reliable with the means of O ¡ C (observed-minus- calculated) residuals in right ascension and declination about 2:7200 and 1:4900. -
Astrometry of Three Near Earth Asteroids with the Lijiang 2.4 M Telescope ∗
RAA 2015 Vol. 15 No. 3, 435–442 doi: 10.1088/1674–4527/15/3/010 Research in http://www.raa-journal.org http://www.iop.org/journals/raa Astronomy and Astrophysics Astrometry of three near Earth asteroids with the Lijiang 2.4 m telescope ¤ Xi-Liang Zhang1;2;3, Yong Yu3, Xue-Li Wang1;2, Chuan-Jun Wang1;2, Liang Chang1;2 Yu-Feng Fan1;2 and Zheng-Hong Tang3 1 Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011, China; [email protected] 2 Key Laboratory of the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650011, China 3 Shanghai Astronomical Observatory, Chinese Academy of Sciences, Shanghai 20030, China Received 2014 April 10; accepted 2014 June 27 Abstract Under the framework of observational campaigns organized by the GAIA Follow Up Network for Solar System Objects, three near Earth asteroids, 367943 Duende, 99942 Apophis and 2013 TV135, were observed with the Lijiang 2.4 m telescope administered by Yunnan Observatories. The software package PRISM was used to calibrate the CCD fields and measure the positions of 99942 Apophis and 2013 TV135, and our own software was used for 367943 Duende. A comparison of the results show that the ephemerides of INPOP10a and JPL are consistent for 99942 Apophis and 2013 TV135, however, they are quite inconsistent for 367943 Duende. Moreover, we have found that differences between the mean values in the ephemerides of INPOP10a and JPL are about 7200 and ¡19900 in right ascension and declination respectively for 367943 Duende. Moreover, the ephemeris published by JPL is reliable in terms of the mean observed-minus-calculated (O ¡ C) residuals in right ascension and declination of about 2:7200 and 1:4900 respectively. -
The Palomar Transient Factory (PTF) Survey & Discovery of Small
The Palomar Transient Factory (PTF) Survey & Discovery of Small Mission-Accessible NEAs Adam Waszczak Graduate Student Division of Geological & Planetary Sciences California Institute of Technology The Palomar Transient Factory (PTF) 48-inch (1.2-m) “Oschin” robotic wide-field imaging [r-band] exposure time: 60s field-of-view: 7.3 deg2 / 11 CCDs limiting mag: r 20.5 resolution: 1.0 arcsec/pixel typical seeing: 2.0 arcsec FWHM The Palomar Transient Factory (PTF) 48-inch (1.2-m) “Oschin” robotic wide-field imaging [r-band] exposure time: 60s field-of-view: 7.3 deg2 / 11 CCDs limiting mag: r 20.5 resolution: 1.0 arcsec/pixel typical seeing: 2.0 arcsec FWHM The Palomar Transient Factory (PTF) 60-inch (1.5-m) robotic imaging follow-up [ugriz-bands & SED machine] 48-inch (1.2-m) “Oschin” robotic wide-field imaging [r-band] The Palomar Transient Factory (PTF) 60-inch (1.5-m) robotic imaging follow-up [ugriz-bands & SED machine] 48-inch (1.2-m) “Oschin” 200-inch (5.2-m) “Hale” robotic wide-field imaging spectroscopic follow-up [DBSP] [r-band] The Palomar Transient Factory (PTF) 60-inch (1.5-m) robotic imaging follow-up [ugriz-bands & SED machine] 48-inch (1.2-m) “Oschin” 200-inch (5.2-m) “Hale” robotic wide-field imaging spectroscopic follow-up [DBSP] [r-band] PTF is a world leader in the discovery and spectroscopic follow-up of extragalactic transients (e.g., supernovae). PTF detections of asteroids in general In past year, PTF submitted over 500,000 observations to the Minor Planet Center.