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Solar System Tests of the Equivalence Principle and Constraints on Higher-Dimensional Gravity
Solar system tests of the equivalence principle and constraints on higher-dimensional gravity J. M. Overduin Department of Physics, University of Waterloo, ON, Canada N2L 3G1 and Gravity Probe B, Hansen Experimental Physics Laboratory, Stanford University, California (July 21, 2000) the theory, ξ and αk refer to possible preferred-location In most studies of equivalence principle violation by solar and preferred-frame effects, and the ζk allow for possible system bodies, it is assumed that the ratio of gravitational to violations of momentum conservation (see [1] for discus- inertial mass for a given body deviates from unity by a param- sion). One has η = 0 in standard general relativity, where eter ∆ which is proportional to its gravitational self-energy. γ = β = 1. In 4D scalar-tensor theories, by contrast, Here we inquire what experimental constraints can be set on γ =(1+ω)/(2 + ω)andβ =1+ω /[2(2 + ω)(3 + 2ω)2], ∆ for various solar system objects when this assumption is re- 0 laxed. Extending an analysis originally due to Nordtvedt, we where ω = ω(φ) is the generalized Brans-Dicke parame- obtain upper limits on linearly independent combinations of ter and ω0 = dω/dφ. ∆ for two or more bodies from Kepler’s third law, the position The relative gravitational self-energy U can be cal- of Lagrange libration points, and the phenomenon of orbital culated for most objects in the solar system, subject polarization. Combining our results, we extract numerical to uncertainties in their mass density profiles. Thus, 5 upper bounds on ∆ for the Sun, Moon, Earth and Jupiter, for example, US 10− for the Sun, while Jupiter 8 ∼− using observational data on their orbits as well as those of the has UJ 10− [3]. -
Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations*
Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations* F. Marchisa,g, J.E. Enriqueza, J. P. Emeryb, M. Muellerc, M. Baeka, J. Pollockd, M. Assafine, R. Vieira Martinsf, J. Berthierg, F. Vachierg, D. P. Cruikshankh, L. Limi, D. Reichartj, K. Ivarsenj, J. Haislipj, A. LaCluyzej a. Carl Sagan Center, SETI Institute, 189 Bernardo Ave., Mountain View, CA 94043, USA. b. Earth and Planetary Sciences, University of Tennessee 306 Earth and Planetary Sciences Building Knoxville, TN 37996-1410 c. SRON, Netherlands Institute for Space Research, Low Energy Astrophysics, Postbus 800, 9700 AV Groningen, Netherlands d. Appalachian State University, Department of Physics and Astronomy, 231 CAP Building, Boone, NC 28608, USA e. Observatorio do Valongo/UFRJ, Ladeira Pedro Antonio 43, Rio de Janeiro, Brazil f. Observatório Nacional/MCT, R. General José Cristino 77, CEP 20921-400 Rio de Janeiro - RJ, Brazil. g. Institut de mécanique céleste et de calcul des éphémérides, Observatoire de Paris, Avenue Denfert-Rochereau, 75014 Paris, France h. NASA Ames Research Center, Mail Stop 245-6, Moffett Field, CA 94035-1000, USA i. NASA/Goddard Space Flight Center, Greenbelt, MD 20771, United States j. Physics and Astronomy Department, University of North Carolina, Chapel Hill, NC 27514, U.S.A * Based in part on observations collected at the European Southern Observatory, Chile Programs Numbers 70.C-0543 and ID 72.C-0753 Corresponding author: Franck Marchis Carl Sagan Center SETI Institute 189 Bernardo Ave. Mountain View CA 94043 USA [email protected] Abstract: We collected mid-IR spectra from 5.2 to 38 µm using the Spitzer Space Telescope Infrared Spectrograph of 28 asteroids representative of all established types of binary groups. -
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. -
Physical Properties of Near-Earth Asteroids
Planet. Space Sci., Vol. 46, No. 1, pp. 47-74, 1998 Pergamon N~I1998 Elsevier Science Ltd All rights reserved. Printed in Great Britain 00324633/98 $19.00+0.00 PII: SOO32-0633(97)00132-3 Physical properties of near-Earth asteroids D. F. Lupishko’ and M. Di Martino’ ’ Astronomical Observatory of Kharkov State University, Sumskaya str. 35, Kharkov 310022, Ukraine ‘Osservatorio Astronomic0 di Torino, I-10025 Pino Torinese (TO), Italy Received 5 February 1997; accepted 20 June 1997 rather small objects, usually of the order of a few kilo- metres or less. MBAs of such sizes are generally not access- ible to ground-based observations. Therefore, when NEAs approach the Earth (at distances which can be as small as 0.01-0.02 AU and sometimes less) they give a unique chance to study objects of such small sizes. Some of them possibly represent primordial matter, which has preserved a record of the earliest stages of the Solar System evolution, while the majority are fragments coming from catastrophic collisions that occurred in the asteroid main- belt and could provide “a look” at the interior of their much larger parent bodies. Therefore, NEAs are objects of special interest for sev- eral reasons. First, from the point of view of fundamental science, the problems raised by their origin in planet- crossing orbits, their life-time, their possible genetic relations with comets and meteorites, etc. are closely connected with the solution of the major problem of “We are now on the threshold of a new era of asteroid planetary science of the origin and evolution of the Solar studies” System. -
Asteroid Family Ages. 2015. Icarus 257, 275-289
Icarus 257 (2015) 275–289 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Asteroid family ages ⇑ Federica Spoto a,c, , Andrea Milani a, Zoran Knezˇevic´ b a Dipartimento di Matematica, Università di Pisa, Largo Pontecorvo 5, 56127 Pisa, Italy b Astronomical Observatory, Volgina 7, 11060 Belgrade 38, Serbia c SpaceDyS srl, Via Mario Giuntini 63, 56023 Navacchio di Cascina, Italy article info abstract Article history: A new family classification, based on a catalog of proper elements with 384,000 numbered asteroids Received 6 December 2014 and on new methods is available. For the 45 dynamical families with >250 members identified in this Revised 27 April 2015 classification, we present an attempt to obtain statistically significant ages: we succeeded in computing Accepted 30 April 2015 ages for 37 collisional families. Available online 14 May 2015 We used a rigorous method, including a least squares fit of the two sides of a V-shape plot in the proper semimajor axis, inverse diameter plane to determine the corresponding slopes, an advanced error model Keywords: for the uncertainties of asteroid diameters, an iterative outlier rejection scheme and quality control. The Asteroids best available Yarkovsky measurement was used to estimate a calibration of the Yarkovsky effect for each Asteroids, dynamics Impact processes family. The results are presented separately for the families originated in fragmentation or cratering events, for the young, compact families and for the truncated, one-sided families. For all the computed ages the corresponding uncertainties are provided, and the results are discussed and compared with the literature. The ages of several families have been estimated for the first time, in other cases the accu- racy has been improved. -
The Minor Planet Bulletin and How the Situation Has Gone from One Mt Tarana Observatory of Trying to Fill Pages to One of Fitting Everything In
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 33, NUMBER 2, A.D. 2006 APRIL-JUNE 29. PHOTOMETRY OF ASTEROIDS 133 CYRENE, adjusted up or down to line up with the V-band data). The near- 454 MATHESIS, 477 ITALIA, AND 2264 SABRINA perfect overlay of V- and R-band data show no evidence of color change as the asteroid rotates. This result replicates the lightcurve Robert K. Buchheim period reported by Harris et al. (1984), and matches the period and Altimira Observatory lightcurve shape reported by Behrend (2005) at his website. 18 Altimira, Coto de Caza, CA 92679 USA [email protected] (Received: 4 November Revised: 21 November) Photometric studies of asteroids 133 Cyrene, 454 Mathesis, 477 Italia and 2264 Sabrina are reported. The lightcurve period for Cyrene of 12.707±0.015 h (with amplitude 0.22 mag) confirms prior studies. The lightcurve period of 8.37784±0.00003 h (amplitude 0.32 mag) for Mathesis differs from previous studies. For Italia, color indices (B-V)=0.87±0.07, (V-R)=0.48±0.05, and phase curve parameters H=10.4, G=0.15 have been determined. For Sabrina, this study provides the first reported lightcurve period 43.41±0.02 h, with 0.30 mag amplitude. Altimira Observatory, located in southern California, is equipped with a 0.28-m Schmidt-Cassegrain telescope (Celestron NexStar- 454 Mathesis. DiMartino et al. (1994) reported a rotation period of 11 operating at F/6.3), and CCD imager (ST-8XE NABG, with 7.075 h with amplitude 0.28 mag for this asteroid, based on two Johnson-Cousins filters). -
On the Accuracy of Restricted Three-Body Models for the Trojan Motion
DISCRETE AND CONTINUOUS Website: http://AIMsciences.org DYNAMICAL SYSTEMS Volume 11, Number 4, December 2004 pp. 843{854 ON THE ACCURACY OF RESTRICTED THREE-BODY MODELS FOR THE TROJAN MOTION Frederic Gabern1, Angel` Jorba1 and Philippe Robutel2 Departament de Matem`aticaAplicada i An`alisi Universitat de Barcelona Gran Via 585, 08007 Barcelona, Spain1 Astronomie et Syst`emesDynamiques IMCCE-Observatoire de Paris 77 Av. Denfert-Rochereau, 75014 Paris, France2 Abstract. In this note we compare the frequencies of the motion of the Trojan asteroids in the Restricted Three-Body Problem (RTBP), the Elliptic Restricted Three-Body Problem (ERTBP) and the Outer Solar System (OSS) model. The RTBP and ERTBP are well-known academic models for the motion of these asteroids, and the OSS is the standard model used for realistic simulations. Our results are based on a systematic frequency analysis of the motion of these asteroids. The main conclusion is that both the RTBP and ERTBP are not very accurate models for the long-term dynamics, although the level of accuracy strongly depends on the selected asteroid. 1. Introduction. The Restricted Three-Body Problem models the motion of a particle under the gravitational attraction of two point masses following a (Keple- rian) solution of the two-body problem (a general reference is [17]). The goal of this note is to discuss the degree of accuracy of such a model to study the real motion of an asteroid moving near the Lagrangian points of the Sun-Jupiter system. To this end, we have considered two restricted three-body problems, namely: i) the Circular RTBP, in which Sun and Jupiter describe a circular orbit around their centre of mass, and ii) the Elliptic RTBP, in which Sun and Jupiter move on an elliptic orbit. -
Planetary Science : a Lunar Perspective
APPENDICES APPENDIX I Reference Abbreviations AJS: American Journal of Science Ancient Sun: The Ancient Sun: Fossil Record in the Earth, Moon and Meteorites (Eds. R. 0.Pepin, et al.), Pergamon Press (1980) Geochim. Cosmochim. Acta Suppl. 13 Ap. J.: Astrophysical Journal Apollo 15: The Apollo 1.5 Lunar Samples, Lunar Science Insti- tute, Houston, Texas (1972) Apollo 16 Workshop: Workshop on Apollo 16, LPI Technical Report 81- 01, Lunar and Planetary Institute, Houston (1981) Basaltic Volcanism: Basaltic Volcanism on the Terrestrial Planets, Per- gamon Press (1981) Bull. GSA: Bulletin of the Geological Society of America EOS: EOS, Transactions of the American Geophysical Union EPSL: Earth and Planetary Science Letters GCA: Geochimica et Cosmochimica Acta GRL: Geophysical Research Letters Impact Cratering: Impact and Explosion Cratering (Eds. D. J. Roddy, et al.), 1301 pp., Pergamon Press (1977) JGR: Journal of Geophysical Research LS 111: Lunar Science III (Lunar Science Institute) see extended abstract of Lunar Science Conferences Appendix I1 LS IV: Lunar Science IV (Lunar Science Institute) LS V: Lunar Science V (Lunar Science Institute) LS VI: Lunar Science VI (Lunar Science Institute) LS VII: Lunar Science VII (Lunar Science Institute) LS VIII: Lunar Science VIII (Lunar Science Institute LPS IX: Lunar and Planetary Science IX (Lunar and Plane- tary Institute LPS X: Lunar and Planetary Science X (Lunar and Plane- tary Institute) LPS XI: Lunar and Planetary Science XI (Lunar and Plane- tary Institute) LPS XII: Lunar and Planetary Science XII (Lunar and Planetary Institute) 444 Appendix I Lunar Highlands Crust: Proceedings of the Conference in the Lunar High- lands Crust, 505 pp., Pergamon Press (1980) Geo- chim. -
Assa Handbook-1993
ASTRONOMICAL HANDBOOK FOR SOUTHERN AFRICA 1 published by the Astronomical Society of Southern Africa 5 A MUSEUM QUEEN VICTORIA STREET (3 61 CAPE TOWN 8000 (021)243330 o PUBLIC SHOWS o MONTHLY SKY UPDATES 0 ASTRONOMY COURSES O MUSIC CONCERTS o ASTRONOMY WEEK 0 SCHOOL SHOWS ° CLUB BOOKINGS ° CORPORATE LAUNCH VENUE FOR MORE INFO PHONE 243330 ASTRONOMICAL HANDBOOK FOR SOUTHERN AFRICA 1993 This booklet is intended both as an introduction to observational astronomy for the interested layman - even if hie interest is only a passing one - and as a handbook for the established amateur or professional astronomer. Front cover The telescope of Ds G. de Beer (right) of the Ladismith Astronomical Society. He, Dr M. Schreuder (left) and the late Mr Ron Dale of the Natal Midlands Centre, are viewing Siriu3 in the daytime with the aid of setting circles. Photograph Mr J. Watson ® t h e Astronomical Society of Southern Africa, Cape Town. 1992 ISSN 0571-7191 CONTENTS ASTRONOMY IN SOUTHERN AFRICA...................... 1 DIARY................................................................. 6 THE SUN............................................................... 8 THE MOON............................................................. 11 THE PLANETS.......................................................... 17 THE MOONS OF JUPITER ................................................ 24 THE MOONS OF SATURN....................................... 28 COMETS AND METEORS............................ 29 THE STARS........................................................... -
The Asteroid Veritas: an Intruder in a Family Named After It? ⇑ Patrick Michel A, , Martin Jutzi B, Derek C
Icarus 211 (2011) 535–545 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus The Asteroid Veritas: An intruder in a family named after it? ⇑ Patrick Michel a, , Martin Jutzi b, Derek C. Richardson c, Willy Benz d a University of Nice-Sophia Antipolis, CNRS, Observatoire de la Côte d’Azur, Cassiopée Laboratory, B.P. 4229, 06304 Nice Cedex 4, France b Earth and Planetary Sciences, University of California, 1156 High Street, Santa Cruz, CA 95064, USA c Department of Astronomy, University of Maryland, College Park, MD 20742-2421, USA d Physicalisches Institut, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland article info abstract Article history: The Veritas family is located in the outer main belt and is named after its apparent largest constituent, Received 19 June 2010 Asteroid (490) Veritas. The family age has been estimated by two independent studies to be quite young, Revised 19 October 2010 around 8 Myr. Therefore, current properties of the family may retain signatures of the catastrophic dis- Accepted 19 October 2010 ruption event that formed the family. In this paper, we report on our investigation of the formation of Available online 29 October 2010 the Veritas family via numerical simulations of catastrophic disruption of a 140-km-diameter parent body, which was considered to be made of either porous or non-porous material, and a projectile impact- Keywords: ing at 3 or 5 km/s with an impact angle of 0° or 45°. Not one of these simulations was able to produce Asteroids satisfactorily the estimated size distribution of real family members. -
Asteroid Regolith Weathering: a Large-Scale Observational Investigation
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2019 Asteroid Regolith Weathering: A Large-Scale Observational Investigation Eric Michael MacLennan University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation MacLennan, Eric Michael, "Asteroid Regolith Weathering: A Large-Scale Observational Investigation. " PhD diss., University of Tennessee, 2019. https://trace.tennessee.edu/utk_graddiss/5467 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Eric Michael MacLennan entitled "Asteroid Regolith Weathering: A Large-Scale Observational Investigation." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Geology. Joshua P. Emery, Major Professor We have read this dissertation and recommend its acceptance: Jeffrey E. Moersch, Harry Y. McSween Jr., Liem T. Tran Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Asteroid Regolith Weathering: A Large-Scale Observational Investigation A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Eric Michael MacLennan May 2019 © by Eric Michael MacLennan, 2019 All Rights Reserved. -
Asteroids + Comets
Datasets for Asteroids and Comets Caleb Keaveney, OpenSpace intern Rachel Smith, Head, Astronomy & Astrophysics Research Lab North Carolina Museum of Natural Sciences 2020 Contents Part 1: Visualization Settings ………………………………………………………… 3 Part 2: Near-Earth Asteroids ………………………………………………………… 5 Amor Asteroids Apollo Asteroids Aten Asteroids Atira Asteroids Potentially Hazardous Asteroids (PHAs) Mars-crossing Asteroids Part 3: Main-Belt Asteroids …………………………………………………………… 12 Inner Main Asteroid Belt Main Asteroid Belt Outer Main Asteroid Belt Part 4: Centaurs, Trojans, and Trans-Neptunian Objects ………………………….. 15 Centaur Objects Jupiter Trojan Asteroids Trans-Neptunian Objects Part 5: Comets ………………………………………………………………………….. 19 Chiron-type Comets Encke-type Comets Halley-type Comets Jupiter-family Comets C 2019 Y4 ATLAS About this guide This document outlines the datasets available within the OpenSpace astrovisualization software (version 0.15.2). These datasets were compiled from the Jet Propulsion Laboratory’s (JPL) Small-Body Database (SBDB) and NASA’s Planetary Data Service (PDS). These datasets provide insights into the characteristics, classifications, and abundance of small-bodies in the solar system, as well as their relationships to more prominent bodies. OpenSpace: Datasets for Asteroids and Comets 2 Part 1: Visualization Settings To load the Asteroids scene in OpenSpace, load the OpenSpace Launcher and select “asteroids” from the drop-down menu for “Scene.” Then launch OpenSpace normally. The Asteroids package is a big dataset, so it can take a few hours to load the first time even on very powerful machines and good internet connections. After a couple of times opening the program with this scene, it should take less time. If you are having trouble loading the scene, check the OpenSpace Wiki or the OpenSpace Support Slack for information and assistance.