Meteor Shower Detection with Density-Based Clustering
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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. -
Assessing Risk from Dangerous Meteoroids in Main Meteor Showers Andrey Murtazov
Proceedings of the IMC, Mistelbach, 2015 155 Assessing risk from dangerous meteoroids in main meteor showers Andrey Murtazov Astronomical observatory, Ryazan State University, Ryazan, Russia [email protected] The risk from dangerous meteoroids in main meteor showers is calculated. The showers were: Quadrantids–2014; Eta Aquariids–2013, Perseids–2014 and Geminids–2014. The computed results for the risks during the shower periods of activity and near the maximum are provided. 1 Introduction The activity periods of these showers (IMO) are: Quadrantids–2014; 1d; Eta Aquariids–2013; 10d, Bright meteors are of serious hazard for space vehicles. Perseids–2014; 14d and Geminids–2014; 4d. A lot of attention has been recently paid to meteor Our calculations have shown that the average collisions N investigations in the context of the different types of of dangerous meteoroids for these showers in their hazards caused by comparatively small meteoroids. activity periods are: Furthermore, the investigation of risk distribution related Quadrantids–2014: N = (2.6 ± 0.5)10-2 km-2; to collisions of meteoroids over 1 mm in diameter with Eta Aquariids–2013: N = (2.8)10-1 km-2; space vehicles is quite important for the long-term Perseids–2014: N = (8.4 ± 0.8)10-2 km-2; forecast regarding the development of space research and Geminids–2014: N = (4.8 ± 0.8)10-2 km-2. circumterrestrial ecology problems (Beech, et al., 1997; Wiegert, Vaubaillon, 2009). Consequently, the average value of collision risk was: Considered hazardous are the meteoroids that create -2 -1 Quadrantids–2014: R = 0.03 km day ; meteors brighter than magnitude 0. -
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 -
EPSC2015-482, 2015 European Planetary Science Congress 2015 Eeuropeapn Planetarsy Science Ccongress C Author(S) 2015
EPSC Abstracts Vol. 10, EPSC2015-482, 2015 European Planetary Science Congress 2015 EEuropeaPn PlanetarSy Science CCongress c Author(s) 2015 Recent meteor showers – models and observations P. Koten (1) and J. Vaubaillon (2) (1) Astronomical Institute of ACSR, Ond řejov, Czech Republic, (2) Institut de mecanique Celeste et de Calcul des Ephemerides, Paris, France ([email protected] / Fax: +420-323-620263) Abstract 3. Meteor showers A number of meteor shower outbursts and storms Among the most studied meteor showers is the occurred in recent years starting with several Leonid Leonids due to recent return of their parent comet. storms around 2000 [1]. The methods of modeling Outbursts and storms between 1998 and 2002 and meteoroid streams became better and more precise. also another event in 2009 were observed and An increasing number of observing systems enabled analyzed. The Draconid outbursts in 2005 and 2011 better coverage of such events. The observers were also covered. Especially the latter was observed provide modelers with an important feedback on intensively using different instruments onboard two precision of their models. Here we present aircraft [4]. comparison of several observational results with the model predictions. 1. Introduction The double station observations using video technique are carried out by the Ondrejov observatory team for many years [2]. Besides the regular observations of the meteor showers the campaigns are also dedicated to predicted meteor storms and outbursts. The team participated to several international campaigns during recent Leonid meteor shower return as well as on the Draconid airborne campaign in 2011. The main goal of this experiment is the determination of the meteor trajectories and orbits and the meteor shower activity is also measured and compared with predictions. -
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 -
7 X 11 Long.P65
Cambridge University Press 978-0-521-85349-1 - Meteor Showers and their Parent Comets Peter Jenniskens Index More information Index a – semimajor axis 58 twin shower 440 A – albedo 111, 586 fragmentation index 444 A1 – radial nongravitational force 15 meteoroid density 444 A2 – transverse, in plane, nongravitational force 15 potential parent bodies 448–453 A3 – transverse, out of plane, nongravitational a-Centaurids 347–348 force 15 1980 outburst 348 A2 – effect 239 a-Circinids (1977) 198 ablation 595 predictions 617 ablation coefficient 595 a-Lyncids (1971) 198 carbonaceous chondrite 521 predictions 617 cometary matter 521 a-Monocerotids 183 ordinary chondrite 521 1925 outburst 183 absolute magnitude 592 1935 outburst 183 accretion 86 1985 outburst 183 hierarchical 86 1995 peak rate 188 activity comets, decrease with distance from Sun 1995 activity profile 188 Halley-type comets 100 activity 186 Jupiter-family comets 100 w 186 activity curve meteor shower 236, 567 dust trail width 188 air density at meteor layer 43 lack of sodium 190 airborne astronomy 161 meteoroid density 190 1899 Leonids 161 orbital period 188 1933 Leonids 162 predictions 617 1946 Draconids 165 upper mass cut-off 188 1972 Draconids 167 a-Pyxidids (1979) 199 1976 Quadrantids 167 predictions 617 1998 Leonids 221–227 a-Scorpiids 511 1999 Leonids 233–236 a-Virginids 503 2000 Leonids 240 particle density 503 2001 Leonids 244 amorphous water ice 22 2002 Leonids 248 Andromedids 153–155, 380–384 airglow 45 1872 storm 380–384 albedo (A) 16, 586 1885 storm 380–384 comet 16 1899 -
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. -
Meteor Showers from Active Asteroids and Dormant Comets in Near-Earth
Planetary and Space Planetary and Space Science 00 (2018) 1–11 Science Meteor showers from active asteroids and dormant comets in near-Earth space: a review Quan-Zhi Ye Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125, U.S.A. Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125, U.S.A. Abstract Small bodies in the solar system are conventionally classified into asteroids and comets. However, it is recently found that a small number of objects can exhibit properties of both asteroids and comets. Some are more consistent with asteroids despite episodic ejections and are labeled as “active asteroids”, while some might be aging comets with depleting volatiles. Ejecta produced by active asteroids and/or dormant comets are potentially detectable as meteor showers at the Earth if they are in Earth-crossing orbits, allowing us to retrieve information about the historic activities of these objects. Meteor showers from small bodies with low and/or intermittent activities are usually weak, making shower confirmation and parent association challenging. We show that statistical tests are useful for identifying likely parent-shower pairs. Comprehensive analyses of physical and dynamical properties of meteor showers can lead to deepen understanding on the history of their parents. Meteor outbursts can trace to recent episodic ejections from the parents, and “orphan” showers may point to historic disintegration events. The flourish of NEO and meteor surveys during the past decade has produced a number of high-confidence parent-shower associations, most have not been studied in detail. More work is needed to understand the formation and evolution of these parent-shower pairs. -
The 2019 Meteor Shower Activity Forecast for Low Earth Orbit 1 Overview
NASA METEOROID ENVIRONMENT OFFICE The 2019 meteor shower activity forecast for low Earth orbit Issued 15 October 2018 The purpose of this document is to provide a forecast of major meteor shower activity in low Earth orbit. Several meteor showers – the Draconids, Perseids, eta Aquariids, Orionids, and potentially the Androme- dids – are predicted to exhibit increased rates in 2019. However, no storms (meteor showers with visual rates exceeding 1000 [1, 2]) are predicted. 1 Overview Both the MSFC stream model [3] and the Egal et al. Draconid model [4] predict a second Draconid outburst in 2019. The 2019 Draconids are expected to have nearly the same level of activity as the 2018 Draconids, which reached a zenithal hourly rate (or ZHR) of about 100. Twin outbursts also occurred in 2011 and 2012 [5, 6]. The Perseids, eta Aquariids, and Orionids are expected to show mild enhancements over their baseline activity level in 2019. The Perseids are expected to be slightly more active in 2019 than in 2018, with a peak ZHR around 112. The eta Aquariids and Orionids, which belong to a single meteoroid stream generated by comet 1P/Halley, are thought to have a 12-year activity cycle and are currently increasing in activity from year to year. A review of eta Aquariid literature [7, 8, 9, 10] also indicates that the overall activity level is higher than previously believed, and this is reflected in higher forecasted rates (a ZHR of 75) and fluxes for this shower. We may see enhanced beta Taurid activity in 2019. The beta Taurids are part of the same stream as the Northern and Southern Taurids but produce daytime meteors. -
David Levy's Guide to the Night Sky Da
Cambridge University Press 0521797535 - David Levy’s Guide to the Night Sky David H. Levy Index More information INDEX AAVSO, 200–201, 331, 332 binoculars, 57–59 absolute magnitudes, 36 Bobrovnikoff method, estimating comet Adams, John Couch, 156 brightness, 178 aetheria darkening, 138 Bode, Johann, 163 Alcock, George, 44, 185 Bode’s Law, 163–165 Algol, 325 Brahe, Tycho, 81 aligning, 67 Brasch, Klaus, 126 Alpha Capricornids, 47 Brashear, John, 60 altazimuth, 62, 65 bright nebulae, 232–233 altitude, 67 Brooks, William, 182 Amalthea, 111 Burnham, Sherbourne Wesley, 193 amateur astronomy, introduced, xvii, xviii Andromedids, 48, 49, 68 Callisto, 111, 119, 121 Antoniadi, Eugenios, 112 Carrington, Christopher, 103 aphelic oppositions, 134 Cassini spacecraft, 130 aphelion, 134 Cassini, Giovanni, 81, 124 apochromat, 60 Cassini’s Division, 124, 125 apparent magnitude, 36 CCD technology, 275–280 apparitions, of comets, 134, 135 CCDs, for astrometry, 283 Arago, Francois, 156 Celestial Police, 163–164 Ariel, 159 celestial equator, 8 ashen light, Venus, 152 Central Bureau for Astronomical Association of Lunar and Planetary Telegrams,120, 121, 186–187, 280 Observers, 331, 332 Challis, James, 156 Asteroids, 163–172 Chapman, Clark, 170 naming of, 165–166 Chaucer, Geoffrey, 318 Astronomical League, 333 chromosphere, 293 astrophotography, 262 Clark, Alvin, 60 Aurigids, 46 Clavius, Christopher, 82 Aurora, 28–33 Collins, Peter, 158, 217 Auroral Data Center in the US, 29 Coma Berenicids, 50 averted vision, 41 comets, 172–189, 294 azimuth, 67 Arend–Roland, 43 Biela, 49, 68 Baker, Lonny, xxii Bradfield, 69 Barnard, E. E. 111, 181–182 Denning–Fujikawa, 181 Beyer method, estimating comet brightness, Encke, 49, 175 179 Giacobini–Zinner, 48 Beyond the Observatory (Shapley), 35 Halley, 44, 46, 48, 55, 78, 175, 225 big bang, 65 Hartley–IRAS, 175 339 © Cambridge University Press www.cambridge.org Cambridge University Press 0521797535 - David Levy’s Guide to the Night Sky David H. -
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. -
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).