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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. -
Temperature-Induced Effects and Phase Reddening on Near-Earth Asteroids
Planetologie Temperature-induced effects and phase reddening on near-Earth asteroids Inaugural-Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften im Fachbereich Geowissenschaften der Mathematisch-Naturwissenschaftlichen Fakultät der Westfälischen Wilhelms-Universität Münster vorgelegt von Juan A. Sánchez aus Caracas, Venezuela -2013- Dekan: Prof. Dr. Hans Kerp Erster Gutachter: Prof. Dr. Harald Hiesinger Zweiter Gutachter: Dr. Vishnu Reddy Tag der mündlichen Prüfung: 4. Juli 2013 Tag der Promotion: 4. Juli 2013 Contents Summary 5 Preface 7 1 Introduction 11 1.1 Asteroids: origin and evolution . 11 1.2 The asteroid-meteorite connection . 13 1.3 Spectroscopy as a remote sensing technique . 16 1.4 Laboratory spectral calibration . 24 1.5 Taxonomic classification of asteroids . 31 1.6 The NEA population . 36 1.7 Asteroid space weathering . 37 1.8 Motivation and goals of the thesis . 41 2 VNIR spectra of NEAs 43 2.1 The data set . 43 2.2 Data reduction . 45 3 Temperature-induced effects on NEAs 55 3.1 Introduction . 55 3.2 Temperature-induced spectral effects on NEAs . 59 3.2.1 Spectral band analysis of NEAs . 59 3.2.2 NEAs surface temperature . 59 3.2.3 Temperature correction to band parameters . 62 3.3 Results and discussion . 70 4 Phase reddening on NEAs 73 4.1 Introduction . 73 4.2 Phase reddening from ground-based observations of NEAs . 76 4.2.1 Phase reddening effect on the band parameters . 76 4.3 Phase reddening from laboratory measurements of ordinary chondrites . 82 4.3.1 Data and spectral band analysis . 82 4.3.2 Phase reddening effect on the band parameters . -
1620 Geographos and 433 Eros: Shaped by Planetary Tides?
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server 1620 Geographos and 433 Eros: Shaped by Planetary Tides? W. F. Bottke, Jr. Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853-6801 D. C. Richardson Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 P. Michel Osservatorio Astronomico di Torino, Strada Osservatorio 20, 10025 Pino Torinese (TO), Italy and S. G. Love Jet Propulsion Laboratory, California Institute of Technology, M/S 306-438, 4800 Oak Grove Drive, Pasadena, CA 91109-8099 Received 23 September 1998; accepted 10 December 1998 –2– ABSTRACT Until recently, most asteroids were thought to be solid bodies whose shapes were determined largely by collisions with other asteroids (Davis et al., 1989). It now seems that many asteroids are little more than rubble piles, held together by self-gravity (Burns 1998); this means that their shapes may be strongly distorted by tides during close encounters with planets. Here we report on numerical simulations of encounters between a ellipsoid-shaped rubble-pile asteroid and the Earth. After an encounter, many of the simulated asteroids develop the same rotation rate and distinctive shape (i.e., highly elongated with a single convex side, tapered ends, and small protuberances swept back against the rotation direction) as 1620 Geographos. Since our numerical studies show that these events occur with some frequency, we suggest that Geographos may be a tidally distorted object. In addition, our work shows that 433 Eros, which will be visited by the NEAR spacecraft in 1999, is much like Geographos, which suggests that it too may have been molded by tides in the past. -
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. -
Thermophysical Modeling of 99942 Apophis: Estimations of Surface Temperature During the April 2029 Close Approach
Apophis T–9 Years 2020 (LPI Contrib. No. 2242) 2069.pdf THERMOPHYSICAL MODELING OF 99942 APOPHIS: ESTIMATIONS OF SURFACE TEMPERATURE DURING THE APRIL 2029 CLOSE APPROACH. K. C. Sorli1 and P. O. Hayne1, 1Laboratory for Atmospheric and Space Physics – University of Colorado Boulder, CO 80303 ([email protected]) Introduction: The April 13, 2029 close approach purposes of calculating temperatures and thermal IR of the ~350-meter asteroid 99942 Apophis offers an fluxes. Our predictions for surface temperatures and unprecedented opportunity to observe a large near-Earth dynamical effects will be directly testable during the asteroid in detail with ground-based observatories. As Janus mission, with an anticipated launch date of 2022. one of the best-studied hazardous objects, with Though the model was constructed with the intent of additional near-miss flybys in coming decades, it is categorizing binary thermal and dynamical behaviors, crucial to planetary defense to understand its properties including binary YORP [5][6], it is easily adaptable to and potential perturbations to its orbit. solitary asteroids. Apophis has been the subject of extensive study, and This model begins by coupling a 1-d thermophysical will continue to be so for years to come. This existing model [7] to a 3-d shape model and computing facet-by- knowledge and the promise of new data makes it an facet temperatures of the surface and near subsurface excellent candidate for modeling subject to during the time period of Apophis’s 2029 close observational constraints. The 2029 close approach will approach. To calculate temperatures, the model is given have a sizable amplifying effect on Apophis’ orbital information about the incoming solar flux on each facet uncertainty, so small dynamical perturbations will be as a function of solar distance and is set to equilibrate required to understand both the conditions of the 2029 for 1 year to allow for subsurface temperature settling. -
An Estimate of the Flux of Apophis-Particle Meteors at Earth
Apophis T–9 Years 2020 (LPI Contrib. No. 2242) 2075.pdf An Estimate of the Flux of Apophis-Particle Meteors at Earth 1 1 2 Robert Melikyan , Beth Ellen Clark , Carl Hergenrother 1 D epartment of Physics and Astronomy, Ithaca College, Ithaca, NY, USA. 2 L unar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA. Near-Earth asteroid (99942) Apophis is meteoroid stream is propagated between 1900 - predicted to make a close encounter with Earth 2029 using an Apophis ephemeris that places the on April 13, 2029. This close encounter will asteroid at its most likely position for the 2029 bring Apophis within 6 Earth radii from our encounter. Unlike most meteoroid stream geocenter providing an excellent opportunity to evolution studies, our simulations release study and observe the asteroid and any particles from Apophis at a regular (~weekly) subsequent effects of the interaction. Here, we rate around its entire orbit, consistent with the bring to your attention the possibility that the Bennu observations. passage of Apophis will not be the only event worth observing. We predict a rain of Apophis Assuming similar particle production meteors that may be detectable to Earth’s meteor mechanisms at Apophis as observed at Bennu, monitoring systems. Apophis could be producing on order of 104 grams of material continuously throughout its NASA’s OSIRIS-REx mission has orbit. Of that material, we assume 30% will recently shown that near-Earth asteroid (101955) escape on hyperbolic trajectories [6]. This Bennu has been continuously producing results in roughly 3500 grams of new material 4 cm-sized ejecta at rates of ~10 grams per orbit entering the Apophis meteoroid stream annually. -
Small Satellite Rendezvous and Characterization of Asteroid 99942 Apophis
SSC09-IV-3 Small Satellite Rendezvous and Characterization of Asteroid 99942 Apophis James Chartres Carnegie Mellon Innovations Laboratory, Carnegie Mellon University Silicon Valley Small Spacecraft Office, NASA Ames Research Center Building 202, Moffett Field, CA 94035; (650) 604-6347 [email protected] David Dunham, Bobby Williams Space Navigation and Flight Dynamics, KinetX, Inc. 2050 E. ASU Circle, Suite 107, Tempe, AZ 85284; (480) 829-6600 [email protected], [email protected] Anthony Genova, Anthony Colaprete, Ronald Johnson, Belgacem Jaroux Small Spacecraft Office, NASA Ames Research Center Building 202, Moffett Field, CA 94035; (650) 604-6347, (650) 604-2918, (650) 604-6699, (650) 604-6312 [email protected], [email protected], [email protected], [email protected] ABSTRACT The Measurement and Analysis of Apophis Trajectory (MAAT) concept study investigated a low-cost characterization mission to the asteroid 99942 Apophis that leverage small spacecraft architectures and technologies. The mission goals were to perform physical characterization and improve the orbital model. The MAAT mission uses a small spacecraft free flyer and a bi-propellant transfer stage that can be incorporated as a secondary payload on Evolved Expendable Launch Vehicles (EELVs), Atlas V or Delta IV launches. Using the innovative secondary architecture allows the system to be launched on numerous GTO or LTO opportunities such as NASA science missions or commercial communication satellites. The trajectory takes advantage of the reduced Delta-V requirement during the 2012- 2015 time frame, with a large flexible launch opportunity, from January to November 2012 and heliocentric injection occurs in April 2013. -
User Provided Data Product Upload of Herschel/PACS Near-Earth Asteroid Observations (Release Note)
Small Bodies: Near and Far NEA HSA UPDP upload User Provided Data Product upload of Herschel/PACS near-Earth asteroid observations (release note) Small Bodies: Near and Far; 687378 – SBNAF – RIA Cs. Kiss1, T.G. M¨uller2, and the SBNAF team 1Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege 15-17, H-1121 Budapest, Hungary 2Max-Planck-Institut f¨ur extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching, Germany Version 1.0 (as of December 29, 2016) Contents 1 Introduction 2 2 Herschel Space Observatory 2 3 Near-Earth asteroid observations 2 4 Data reduction and calibration 3 5Results 3 5.1 (101955) Bennu . 5 5.2 175706 (1996 FG 3) . 5 5.3 308635 (2005 YU 55) . 5 5.4 (162173) Ryugu . 6 5.5 (99942) Apophis . 6 References 7 Appendix 8 Summary of uploaded data products . 8 Summary of additional FITS keywords . 11 Page 1 Small Bodies: Near and Far NEA HSA UPDP upload 1 Introduction SMALL BODIES: NEAR AND FAR is a Horizon 2020 project (project number: 687378) that addresses critical points in reconstructing physical and thermal properties of near- Earth, main-belt, and trans-Neptunian objects (see the project webpage for details: http://www.mpe.mpg.de/ tmueller/sbnaf/). One of the goals of the SBNAF project is to produce a set of high-quality data products for Herschel observations of Solar System objects for an upload to the Herschel Science Archive (HSA). These new products will then be available for the entire scientific community, in parallel to the standard pipeline-processed Herschel archive data. -
The Atlantic Online | June 2008 | the Sky Is Falling | Gregg Easterbrook
The Atlantic Online | June 2008 | The Sky Is Falling | Gregg Easter... http://www.theatlantic.com/doc/print/200806/asteroids Print this Page Close Window JUNE 2008 ATLANTIC MONTHLY The odds that a potentially devastating space rock will hit Earth this century may be as high as one in 10. So why isn’t NASA trying harder to prevent catastrophe? BY GREGG EASTERBROOK The Sky Is Falling Image credit: Stéphane Guisard, www.astrosurf.com/sguisard ALSO SEE: reakthrough ideas have a way of seeming obvious in retrospect, and about a decade ago, a B Columbia University geophysicist named Dallas Abbott had a breakthrough idea. She had been pondering the craters left by comets and asteroids that smashed into Earth. Geologists had counted them and concluded that space strikes are rare events and had occurred mainly during the era of primordial mists. But, Abbott realized, this deduction was based on the number of craters found on land—and because 70 percent of Earth’s surface is water, wouldn’t most space objects hit the sea? So she began searching for underwater craters caused by impacts VIDEO: "TARGET EARTH" rather than by other forces, such as volcanoes. What she has found is spine-chilling: evidence Gregg Easterbrook leads an illustrated that several enormous asteroids or comets have slammed into our planet quite recently, in tour through the treacherous world of space rocks. geologic terms. If Abbott is right, then you may be here today, reading this magazine, only because by sheer chance those objects struck the ocean rather than land. Abbott believes that a space object about 300 meters in diameter hit the Gulf of Carpentaria, north of Australia, in 536 A.D. -
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. -
Radar Observations of Asteroid 1620 Geographos
ICARUS 121, 46±66 (1996) ARTICLE NO. 0071 Radar Observations of Asteroid 1620 Geographos STEVEN J. OSTRO,RAYMOND F. JURGENS, AND KEITH D. ROSEMA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109±8099 E-mail: [email protected] R. SCOTT HUDSON School of Electrical Engineering and Computer Science, Washington State University, Pullman, Washington 99164±2752 AND JON D. GIORGINI,RON WINKLER,DONALD K. YEOMANS,DENNIS CHOATE,RANDY ROSE,MARTIN A. SLADE, S. DENISE HOWARD,DANIEL J. SCHEERES, AND DAVID L. MITCHELL Jet Propulsion Laboratory, Pasadena, California 91109±8099 Received July 31, 1995; revised October 30, 1995 1. INTRODUCTION Goldstone radar observations of Geographos from August 28 through September 2, 1994 yield over 400 delay-Doppler images whose linear spatial resolutions range from p75 to Asteroid 1620 Geographos was discovered in 1951 by p151 m, and 138 pairs of dual-polarization (OC, SC) spectra A. G. Wilson and R. Minkowski and was observed over with one-dimensional resolution of 103 m. Each data type an eight-month interval in 1969 by Dunlap (1974) for ``light provides thorough rotational coverage. The images contain variation, colors, and polarization.'' From his analysis, an intrinsic north/south ambiguity, but the equatorial view which included experiments with laboratory models (Dun- allows accurate determination of the shape of the radar- lap 1972), he estimated the asteroid's spin vector and geo- facing part of the asteroid's pole-on silhouette at any rotation metric albedo, and noted that ``the best ®tting model (a phase. Sums of co-registered images that cover nearly a full cylinder with hemispherical ends) had a length to width rotation have de®ned the extremely elongated shape of that ratio of 2.7, which results in Geographos being 1.50 6 0.15 silhouette (S. -
Orders of Magnitude (Length) - Wikipedia
03/08/2018 Orders of magnitude (length) - Wikipedia Orders of magnitude (length) The following are examples of orders of magnitude for different lengths. Contents Overview Detailed list Subatomic Atomic to cellular Cellular to human scale Human to astronomical scale Astronomical less than 10 yoctometres 10 yoctometres 100 yoctometres 1 zeptometre 10 zeptometres 100 zeptometres 1 attometre 10 attometres 100 attometres 1 femtometre 10 femtometres 100 femtometres 1 picometre 10 picometres 100 picometres 1 nanometre 10 nanometres 100 nanometres 1 micrometre 10 micrometres 100 micrometres 1 millimetre 1 centimetre 1 decimetre Conversions Wavelengths Human-defined scales and structures Nature Astronomical 1 metre Conversions https://en.wikipedia.org/wiki/Orders_of_magnitude_(length) 1/44 03/08/2018 Orders of magnitude (length) - Wikipedia Human-defined scales and structures Sports Nature Astronomical 1 decametre Conversions Human-defined scales and structures Sports Nature Astronomical 1 hectometre Conversions Human-defined scales and structures Sports Nature Astronomical 1 kilometre Conversions Human-defined scales and structures Geographical Astronomical 10 kilometres Conversions Sports Human-defined scales and structures Geographical Astronomical 100 kilometres Conversions Human-defined scales and structures Geographical Astronomical 1 megametre Conversions Human-defined scales and structures Sports Geographical Astronomical 10 megametres Conversions Human-defined scales and structures Geographical Astronomical 100 megametres 1 gigametre