Search for Meteor Showers Associated with Near-Earth Asteroids
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Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar End
N9 Spacewalch Discovery of Near-Earth Asteroids Tom Gehrele Lunar end Planetary Laboratory The University of Arizona Our overall scientific goal is to survey the solar system to completion -- that is, to find the various populations and to study their statistics, interrelations, and origins. The practical benefit to SERC is that we are finding Earth-approaching asteroids that are accessible for mining. Our system can detect Earth-approachers In the 1-km size range even when they are far away, and can detect smaller objects when they are moving rapidly past Earth. Until Spacewatch, the size range of 6 - 300 meters in diameter for the near-Earth asteroids was unexplored. This important region represents the transition between the meteorites and the larger observed near-Earth asteroids (Rabinowitz 1992). One of our Spacewatch discoveries, 1991 VG, may be representative of a new orbital class of object. If it is really a natural object, and not man-made, its orbital parameters are closer to those of the Earth than we have seen before; its delta V is the lowest of all objects known thus far (J. S. Lewis, personal communication 1992). We may expect new discoveries as we continue our surveying, with fine-tuning of the techniques. III-12 Introduction The data accumulated in the following tables are the result of continuing observation conducted as a part of the Spacewatch program. T. Gehrels is the Principal Investigator and also one of the three observers, with J.V. Scotti and D.L Rabinowitz, each observing six nights per month. R.S. McMillan has been Co-Principal Investigator of our CCD-scanning since its inception; he coordinates optical, mechanical, and electronic upgrades. -
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A&A 598, A40 (2017) Astronomy DOI: 10.1051/0004-6361/201629659 & c ESO 2017 Astrophysics Separation and confirmation of showers? L. Neslušan1 and M. Hajduková, Jr.2 1 Astronomical Institute, Slovak Academy of Sciences, 05960 Tatranska Lomnica, Slovak Republic e-mail: [email protected] 2 Astronomical Institute, Slovak Academy of Sciences, Dubravska cesta 9, 84504 Bratislava, Slovak Republic e-mail: [email protected] Received 6 September 2016 / Accepted 30 October 2016 ABSTRACT Aims. Using IAU MDC photographic, IAU MDC CAMS video, SonotaCo video, and EDMOND video databases, we aim to separate all provable annual meteor showers from each of these databases. We intend to reveal the problems inherent in this procedure and answer the question whether the databases are complete and the methods of separation used are reliable. We aim to evaluate the statistical significance of each separated shower. In this respect, we intend to give a list of reliably separated showers rather than a list of the maximum possible number of showers. Methods. To separate the showers, we simultaneously used two methods. The use of two methods enables us to compare their results, and this can indicate the reliability of the methods. To evaluate the statistical significance, we suggest a new method based on the ideas of the break-point method. Results. We give a compilation of the showers from all four databases using both methods. Using the first (second) method, we separated 107 (133) showers, which are in at least one of the databases used. These relatively low numbers are a consequence of discarding any candidate shower with a poor statistical significance. -
Using Resources from Near-Earth Space
USING RESOURCES FROM NEAR-EARTH SPACE JOHN S. LEWIS University of Arizona DAVIDS. McKAY NASA Johnson Space Center and BENTON C. CLARK Martin Marietta Civil Space & Communications The parts of the solar system that are most accessible from Earth (the Moon, the near Earth asteroids, and Mars and its moons) are rich in materials of great potential value to humanity. Immediate uses of these resources to manufacture propellants, structural metals, refractories, life-support fluids and glass can support future large-scale space acitivites. In the longterm, non-terrestrial sources of rare materials and energy may be of great importance here on Earth. I. INTRODUCTION Space activities have become so much a part of modem life that they are almost invisible. We are aware how important communications satellite relays are for inexpensive long-distance telephone calls and television news broadcast, and we see the color images of Earth's cloud cover in the weather reports on TV. But we are usually not aware that the commercial airplane in which we fly or the ferry we ride locates itself by using navigation satellites 12,000 miles above our heads. We may never hear that the Soviet Union launched several satellites each year dedicated to assessing the American, Canadian, and Argentine wheat crops to help plan their grain purchases. We may be even more astonished to know that the truck we just passed on the highway is being tracked by a satellite, or that the strategic balance between the great powers has long been monitored based on photographic, electronic imaging, radar, infrared, and signal monitoring from space. -
Meteor Showers' Activity and Forecasting
Meteoroids 2007 – Barcelona, June 11-15 About the cover: The recent fall of the Villalbeto de la Peña meteorite on January 4, 2004 (Spain) is one of the best documented in history for which atmospheric and orbital trajectory, strewn field area, and recovery circumstances have been described in detail. Photometric and seismic measurements together with radioisotopic analysis of several recovered specimens suggest an original mass of about 760 kg. About fifty specimens were recovered from a strewn field of nearly 100 km2. Villalbeto de la Peña is a moderately shocked (S4) equilibrated ordinary chondrite (L6) with a cosmic-ray-exposure age of 48±5 Ma. The chemistry and mineralogy of this genuine meteorite has been characterized in detail by bulk chemical analysis, electron microprobe, electron microscopy, magnetism, porosimetry, X-ray diffraction, infrared, Raman, and 57Mössbauer spectroscopies. The picture of the fireball was taken by M.M. Ruiz and was awarded by the contest organized by the Spanish Fireball Network (SPMN) for the best photograph of the event. The Moon is also visible for comparison. The picture of the meteorite was taken as it was found by the SPMN recovery team few days after the fall. 2 Meteoroids 2007 – Barcelona, June 11-15 FINAL PROGRAM Monday, June 11 Auditorium conference room 9h00-9h50 Reception 9h50-10h00 Opening event Session 1: Observational Techniques and Meteor Detection Programs Morning session Session chairs: J. Borovicka and W. Edwards 10h00-10h30 Pavel Spurny (Ondrejov Observatory, Czech Republic) et al. “Fireball observations in Central Europe and Western Australia – instruments, methods and results” (invited) 10h30-10h45 Josep M. -
17. a Working List of Meteor Streams
PRECEDING PAGE BLANK NOT FILMED. 17. A Working List of Meteor Streams ALLAN F. COOK Smithsonian Astrophysical Observatory Cambridge, Massachusetts HIS WORKING LIST which starts on the next is convinced do exist. It is perhaps still too corn- page has been compiled from the following prehensive in that there arc six streams with sources: activity near the threshold of detection by pho- tography not related to any known comet and (1) A selection by myself (Cook, 1973) from not sho_m to be active for as long as a decade. a list by Lindblad (1971a), which he found Unless activity can be confirmed in earlier or from a computer search among 2401 orbits of later years or unless an associated comet ap- meteors photographed by the Harvard Super- pears, these streams should probably be dropped Sehmidt cameras in New Mexico (McCrosky and from a later version of this list. The author will Posen, 1961) be much more receptive to suggestions for dele- (2) Five additional radiants found by tions from this list than he will be to suggestions McCrosky and Posen (1959) by a visual search for additions I;o it. Clear evidence that the thresh- among the radiants and velocities of the same old for visual detection of a stream has been 2401 meteors passed (as in the case of the June Lyrids) should (3) A further visual search among these qualify it for permanent inclusion. radiants and velocities by Cook, Lindblad, A comment on the matching sets of orbits is Marsden, McCrosky, and Posen (1973) in order. It is the directions of perihelion that (4) A computer search -
Meteor Shower Detection with Density-Based Clustering
Meteor Shower Detection with Density-Based Clustering Glenn Sugar1*, Althea Moorhead2, Peter Brown3, and William Cooke2 1Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305 2NASA Meteoroid Environment Office, Marshall Space Flight Center, Huntsville, AL, 35812 3Department of Physics and Astronomy, The University of Western Ontario, London N6A3K7, Canada *Corresponding author, E-mail: [email protected] Abstract We present a new method to detect meteor showers using the Density-Based Spatial Clustering of Applications with Noise algorithm (DBSCAN; Ester et al. 1996). DBSCAN is a modern cluster detection algorithm that is well suited to the problem of extracting meteor showers from all-sky camera data because of its ability to efficiently extract clusters of different shapes and sizes from large datasets. We apply this shower detection algorithm on a dataset that contains 25,885 meteor trajectories and orbits obtained from the NASA All-Sky Fireball Network and the Southern Ontario Meteor Network (SOMN). Using a distance metric based on solar longitude, geocentric velocity, and Sun-centered ecliptic radiant, we find 25 strong cluster detections and 6 weak detections in the data, all of which are good matches to known showers. We include measurement errors in our analysis to quantify the reliability of cluster occurrence and the probability that each meteor belongs to a given cluster. We validate our method through false positive/negative analysis and with a comparison to an established shower detection algorithm. 1. Introduction A meteor shower and its stream is implicitly defined to be a group of meteoroids moving in similar orbits sharing a common parentage. -
Meteor Showers # 11.Pptx
20-05-31 Meteor Showers Adolf Vollmy Sources of Meteors • Comets • Asteroids • Reentering debris C/2019 Y4 Atlas Brett Hardy 1 20-05-31 Terminology • Meteoroid • Meteor • Meteorite • Fireball • Bolide • Sporadic • Meteor Shower • Meteor Storm Meteors in Our Atmosphere • Mesosphere • Atmospheric heating • Radiant • Zenithal Hourly Rate (ZHR) 2 20-05-31 Equipment Lounge chair Blanket or sleeping bag Hot beverage Bug repellant - ThermaCELL Camera & tripod Tracking Viewing Considerations • Preparation ! Locate constellation ! Take a nap and set alarm ! Practice photography • Location: dark & unobstructed • Time: midnight to dawn https://earthsky.org/astronomy- essentials/earthskys-meteor-shower- guide https://www.amsmeteors.org/meteor- showers/meteor-shower-calendar/ • Where to look: 50° up & 45-60° from radiant • Challenges: fatigue, cold, insects, Moon • Recording observations ! Sky map, pen, red light & clipboard ! Time, position & location ! Recording device & time piece • Binoculars Getty 3 20-05-31 Meteor Showers • 112 confirmed meteor showers • 695 awaiting confirmation • Naming Convention ! C/2019 Y4 (Atlas) ! (3200) Phaethon June Tau Herculids (m) Parent body: 73P/Schwassmann-Wachmann Peak: June 2 – ZHR = 3 Slow moving – 15 km/s Moon: Waning Gibbous June Bootids (m) Parent body: 7p/Pons-Winnecke Peak: June 27– ZHR = variable Slow moving – 14 km/s Moon: Waxing Crescent Perseid by Brian Colville 4 20-05-31 July Delta Aquarids Parent body: 96P/Machholz Peak: July 28 – ZHR = 20 Intermediate moving – 41 km/s Moon: Waxing Gibbous Alpha -
Long Grazing and Slow Trail Fireball Over Portugal Spectra of Slow
e-Zine for meteor observers meteornews.org Vol. 4 / January 2017 A bright fireball photographed by four stations of the Danish Meteor network on December 25 at 2:11 UT. Long grazing and slow trail OCT outburst model comparisons fireball over Portugal in the years 2005, 2016, 2017 Spectra of slow bolides Worldwide radio results The PRO-AM Lunar Impact autumn 2016 project Exoss Fireball events 2016 – 4 eMeteorNews Contents Spectra of slow bolides Jakub Koukal ........................................................................................................................................... 117 Visual observing reports Paul Jones ............................................................................................................................................... 123 Fireball events Compiled by Paul Roggemans ................................................................................................................ 130 CAMS BeNeLux September results Carl Johannink ........................................................................................................................................ 134 October Camelopardalis outburst model comparisons in the years 2005, 2016, 2017 Esko Lyytinen .......................................................................................................................................... 135 CAMS Benelux contributed 4 OCT orbits Carl Johannink ....................................................................................................................................... -
Smithsonian Contributions Astrophysics
SMITHSONIAN CONTRIBUTIONS to ASTROPHYSICS Number 14 Discrete Levels off Beginning Height off Meteors in Streams By A. F. Cook Number 15 Yet Another Stream Search Among 2401 Photographic Meteors By A. F. Cook, B.-A. Lindblad, B. G. Marsden, R. E. McCrosky, and A. Posen Smithsonian Institution Astrophysical Observatory Smithsonian Institution Press SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS NUMBER 14 A. F. cook Discrete Levels of Beginning Height of Meteors in Streams SMITHSONIAN INSTITUTION PRESS CITY OF WASHINGTON 1973 Publications of the Smithsonian Institution Astrophysical Observatory This series, Smithsonian Contributions to Astrophysics, was inaugurated in 1956 to provide a proper communication for the results of research conducted at the Astrophysical Observatory of the Smithsonian Institution. Its purpose is the "increase and diffusion of knowledge" in the field of astrophysics, with particular emphasis on problems of the sun, the earth, and the solar system. Its pages are open to a limited number of papers by other investigators with whom we have common interests. Another series, Annals of the Astrophysical Observatory, was started in 1900 by the Observa- tory's first director, Samuel P. Langley, and was published about every ten years. These quarto volumes, some of which are still available, record the history of the Observatory's researches and activities. The last volume (vol. 7) appeared in 1954. Many technical papers and volumes emanating from the Astrophysical Observatory have appeared in the Smithsonian Miscellaneous Collections. Among these are Smithsonian Physical Tables, Smithsonian Meteorological Tables, and World Weather Records. Additional information concerning these publications can be obtained from the Smithsonian Institution Press, Smithsonian Institution, Washington, D.C. -
3D/Biela and the Andromedids: Fragmenting Versus Sublimating Comets P
The Astronomical Journal, 134:1037 Y 1045, 2007 September # 2007. The American Astronomical Society. All rights reserved. Printed in U.S.A. 3D/BIELA AND THE ANDROMEDIDS: FRAGMENTING VERSUS SUBLIMATING COMETS P. Jenniskens1 and J. Vaubaillon2 Received 2007 January 3; accepted 2007 April 22 ABSTRACT Comet 3D/Biela broke up in 1842/1843 and continued to disintegrate in the returns of 1846 and 1852. When meteor storms were observed in November of 1872 and 1885, it was surmised that those showers were the debris from that breakup. This could have come from one of two sources: (1) the initial separation of fragments near aphelion or (2) the continued disintegration of the fragments afterward. Alternatively, the meteoroids could simply have come from water vapor drag when the fragments approached perihelion (option 3). We investigated the source of the Andromedid storms by calculating the dynamical evolution of dust ejected in a normal manner by water vapor drag in the returns from 1703 to 1866, assuming that the comet would have remained similarly active over each return. In addition, we simulated the isotropic ejection of dust during the initial fragmentation event at aphelion in December of 1842. We conclude that option 2 is the most likely source of meteoroids encountered during the 1872 and 1885 storms, but this accounts for only a relatively small amount of mass lost in a typical comet breakup. Key words: comets: individual (3D/Biela) — meteors, meteoroids — minor planets, asteroids 1. INTRODUCTION 2. THE COMET AND ITS SHOWER Ever since Whipple (1951) showed that water vapor can ac- 2.1. -
2P/Encke, the Taurid Complex Neos and the Maribo and Sutter's Mill Meteorites
A&A 584, A97 (2015) Astronomy DOI: 10.1051/0004-6361/201425512 & c ESO 2015 Astrophysics 2P/Encke, the Taurid complex NEOs and the Maribo and Sutter’s Mill meteorites? C. Tubiana1, C. Snodgrass2;1, R. Michelsen3, H. Haack3, H. Böhnhardt1, A. Fitzsimmons4, and I. P. Williams5 1 Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 33077 Göttingen, Germany e-mail: [email protected] 2 Planetary and Space Sciences, Department of Physical Sciences, The Open University, Milton Keynes, MK7 6AA, UK 3 Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, 1350 Copenhagen, Denmark 4 Astrophysics Research Centre, Department of Physics and Astronomy, Queen’s University Belfast, Belfast BT7 1NN, UK 5 School of Physics and Astronomy, Queen Mary, University of London, London E1 4NS, UK Received 12 December 2014 / Accepted 29 September 2015 ABSTRACT Aims. 2P/Encke is a short period comet that was discovered in 1786 and has been extensively observed and studied for more than 200 years. The Taurid meteoroid stream has long been linked with 2P/Encke owing to a good match of their orbital elements, even though the comet’s activity is not strong enough to explain the number of observed meteors. Various small near-Earth objects (NEOs) have been discovered with orbits that can be linked to 2P/Encke and the Taurid meteoroid stream. Maribo and Sutter’s Mill are CM type carbonaceous chondrite that fell in Denmark on January 17, 2009 and April 22, 2012, respectively. Their pre-atmospheric orbits place them in the middle of the Taurid meteoroid stream, which raises the intriguing possibility that comet 2P/Encke could be the parent body of CM chondrites. -
Radio Echo Observations of Meteors in the Southern Hemisphere
RADIO ECHO OBSERVATIONS OF METEORS IN THE SOUTHERN HEMISPHERE By A. A. WEISS* [Manuscript received September 20, 1954] Summary The results of a radio survey of meteor activity at Adelaide are presented. The radiants and activities of six major meteor showers (Geminids, day-time Arietids, ~-Perseids, a-Aquarids, Corona Australids, Orionids) have been measured by methods which are described, and the mass distributions in three of these showers are discussed. Seasonal and diurnal variations in the background activity of sporadic meteors are examined in relation to the radiation patterns of the aerial systems_ Height distribut.ions for meteors of three showers (Geminids, day-time Arietids, ~-Perseids) are given. Diurnal variations in the height distribution of sporadic meteors do not conform to those expected from the motion of the apex of the Earth's way. I. INTRODUCTION The successful application, at the Jodrell Bank Experimental Station of the University of Manchester, of radio echo techniques to the continuous monitoring of meteor activity in the northern hemisphere, prompted the initiation ()f a complementary survey in the southern hemisphere. Up to the time of (lommencement of this survey lists of southern hemisphere visual observations had been published by McIntosh and by Hoffmeister, and McIntosh (1935) had compiled" An Index to Southern Meteor Showers" which lists 320 radiants visible at mid-southern latitudes. These visual observations have since been supplemented by radio echo observations on the a-Aquarid shower by Hawkins and Almond (1952) and by Lindblad (1952). Although it is certain that all major southern night-time showers have been detected by the visual workers, the cover in the months September to March is not altogether satisfactory (McIntosh 1935).