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Major Meteor Showers Throughout the Year
Major Meteor Showers Throughout the Year Courtesy of The Catawba Valley Astronomy Club - www.catawbasky.org Information taken from http://www.amsmeteors.org/showers.html The meteor showers discussed below recur each year; in some cases they have been recognized for hundreds of years. The name of the shower in most cases indicates the constellation from which the meteors appear. Sporadic meteors are those random meteors not associated with a particular shower; they are the random detritus left over from the creation of the solar system or are old dispersed debris not recognizable today as shower meteors. For meteor observers, those located in the northern hemisphere have a distinct advantage as shower activity is stronger there than that seen by observers located south of the equator. The reason for this is that most of the major showers have meteors that strike the Earth in areas located far above the equator. As seen from the northern hemisphere these meteors would appear to rain down from high in the sky in all directions. The year begins with the intense but brief Quadrantid maximum (January 3/4). Its brevity combined with typically poor winter weather hampers observation. January overall has good meteor rates restricted to the last third of the night. Rates to 20/hour can be obtained. A large number of radiants spread along the ecliptic from Cancer to Virgo. This activity diminishes somewhat in February with the same areas active. Late-night rates are fair in the first half of March, but become poor rather suddenly after mid-March. The very poor rates, seldom reaching 10/hour, continue into early June. -
Geminid Meteor Shower Activity Should Increase
EPSC Abstracts Vol. 12, EPSC2018-397, 2018 European Planetary Science Congress 2018 EEuropeaPn PlanetarSy Science CCongress c Author(s) 2018 Geminid meteor shower activity should increase Galina O. Ryabova (1), Jurgen Rendtel (2) (1) Research Institute of Applied Mathematics and Mechanics of Tomsk State University, Tomsk, Russian Federation ([email protected]), (2) Leibniz-Institut fur Astrophysik Potsdam (AIP), Germany Abstract 2. Model Mathematical modelling has shown that activity of We used one a model with meteoroids of the ‘visual’ the Geminid meteor shower should rise with time, mass of 0.02 g from [6] and extended it until 2025 and that was confirmed by analysis of visual January 1. The model consists of 30 000 meteoroids observations 1985–2017. generated around starting epoch JD 1720165.2248 (perihelion passage) using, as we mentioned, the cometary scenario of ejection. For details of the 1. Introduction model, method, and references, see [6]. The Geminid meteor shower is an annual major shower with the maximum activity on December 14. Why activity should increase? The answer is clear In 2017, asteroid (3200) Phaethon, recognised parent from Fig. 1. Phaethon’s node and the mean orbit of body of the stream, had a close encounter with the the stream (i.e. the densest part of the stream) Earth on December 16. When the Earth passes closer gradually approach the Earth’s orbit. So the Geminid to a parent body orbit of a meteoroid stream, an shower activity should increase slowly. Why we increased activity of the shower is expected. We should not expect an outburst? Because the Geminid elaborated the model to see, if it is the case, and stream had no replenishment after the initial made a comparison with visual and video catastrophic generation [2, 6]. -
Download This Article in PDF Format
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. -
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. -
Backyard Astronomy Santa Fe Public Library
Backyard Astronomy Santa Fe Public Library Photo Credit: NASA, A Mess of Stars,08-10-2015 1. What will you need? 2. What am I looking at? 3. What you can See a. August 2020 b. September 2020 c. October 2020 4. Star Stories 5. Activities a. Tracking the Sunset/Sunrise b. Moon Watching c. Tracking the International Space Station d. Constellation Discovery 6. What to Read Backyard Astronomy Santa Fe Public Library What will you need? The most important things you will need are your curiosity, your naked eyes, and the ability to observe. You do not need fancy telescopes to begin enjoying the wonders of our amazing night skies. Here in Northern New Mexico, we are blessed with the ability to step out of our homes, look up, and see the Milky Way displayed above us without too much obstruction. Photo Credit: NASA, A Glimpse of the Milky Way, 12-13-2005 While the following Items can help you to begin exploring the wonders of the Universe, they are not required. These items include: 1. Binoculars 2. Telescope (a small inexpensive one is fine) 3. Star Chart Planisphere 4. Free Astronomy Apps for both iPhones and Androids There are several really good free apps that help you identify, locate, and track celestial objects. One that I use is Star Walk 2 but there are other good apps available. Backyard Astronomy Santa Fe Public Library What am I looking at? When you look up at night, what do you see? Probably more than you think! Below is a list of the Celestial Items you can see. -
Multi-Instrumental Observations of the 2014 Ursid Meteor Outburst
Multi‐instrumental observations of the 2014 Ursid meteor outburst Monthly Notices of the Royal Astronomical Society, Volume 468, Issue 2, p.2206‐2213 Manuel Moreno‐Ibáñez, Josep Ma. Trigo‐Rodríguez, José María Madiedo, Jérémie Vaubaillon, Iwan P. Williams, Maria Gritsevich, Lorenzo G. Morillas, Estefanía Blanch, Pep Pujols, François Colas, Philippe Dupouy ‐ Instituto de Ciencias del Espacio ‐ 2014 Ursid meteor shower 1. Introduction Why so poor work on the Ursids? Why so poor work on the Ursids? • Similar date than Geminids, which • Similar date than Geminids, which are are more predictable and more predictable and numerous. numerous. • Usually low ZHR? (<10) • Usually low ZHR (<10) • Bad weather conditions in mid‐ • Bad weather conditions in mid‐ December. December. Any explanation? Why are they interesting? • ZHR > 100 when the comet is • Mean motion resonances. at its aphelion. • The meteor swarms detached during • This increase occurs each 13.6 certain years evolve to a different orbit an years approx. get trapped in a 7:6 resonance with • Annual shower? also increases Jupiter=> Period ?roughly fixed. remarkably when the comet is • T swarm/ T comet = 1,011 => In around 45 at its perihelion but not or 46 orbits the comet and the swarm are always. out of phase. 2 2014 Ursid meteor shower 1. Introduction Who is their parent body? Why so poor work on the Ursids? • Comet 8P/Tuttle (Ceplecha (1951)) • Similar date than Geminids, which are • Jupiter Family more predictable and numerous. • Trapped in a 15:13 resonance with • Usually low ZHR (<10) Jupiter => T~13.6 yr. • Bad weather conditions in mid‐ • Aphelion: 10 AU.