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136, June 2008
British Astronomical Association VARIABLE STAR SECTION CIRCULAR No 136, June 2008 Contents Group Photograph, AAVSO/BAAVSS meeting ........................ inside front cover From the Director ............................................................................................... 1 Eclipsing Binary News ....................................................................................... 4 Experiments in the use of a DSLR camera for V photometry ............................ 5 Joint Meeting of the AAVSO and the BAAVSS ................................................. 8 Coordinated HST and Ground Campaigns on CVs ............................... 8 Eclipsing Binaries - Observational Challenges .................................................. 9 Peer to Peer Astronomy Education .................................................................. 10 AAVSO Acronyms De-mystified in Fifteen Minutes ...................................... 11 New Results on SW Sextantis Stars and Proposed Observing Campaign ........ 12 A Week in the Life of a Remote Observer ........................................................ 13 Finding Eclipsing Binaries in NSVS Data ......................................................... 13 British Variable Star Associations 1848-1908 .................................................. 14 “Chasing Rainbows” (The European Amateur Spectroscopy Scene) .............. 15 Long Term Monitoring and the Carbon Miras ................................................. 18 Cataclysmic Variables from Large Surveys: A Silent Revolution -
Observation of Near-Earth Object (1566) Icarus and the Split Candidate 2007 MK6
PPS07-P07 JpGU-AGU Joint Meeting 2017 Observation of near-earth object (1566) Icarus and the split candidate 2007 MK6 *Seitaro Urakawa1, Katsutoshi Ohtsuka2, Shinsuke Abe3, Daisuke Kinoshita4, Hidekazu Hanayama 5, Takeshi Miyaji5, Shin-ichiro Okumura1, Kazuya Ayani6, Syouta Maeno6, Daisuke Kuroda5, Akihiko Fukui5, Norio Narita5,7,8, George HASHIMOTO9, Yuri SAKURAI9, Sayuri Nakamura9, Jun Takahashi10, Tomoyasu Tanigawa11, Otabek Burhonov12, Kamoliddin Ergashev12, Takashi Ito5, Fumi Yoshida5, Makoto Watanabe13, Masataka Imai14, Kiyoshi Kuramoto14, Tomohiko Sekiguchi15 , MASATERU ISHIGURO16 1. Japan Spaceguard Association, 2. Tokyo Meteor Network, 3. Nihon University, 4. National Central University, 5. National Astronomical Observatory of Japan, 6. Bisei Observatory, 7. Astrobiology Center, 8. University of Tokyo, 9. Okayama University, 10. University of Hyogo, 11. Sanda Shounkan Highschool, 12. Ulugh Beg Astronomical Institute Uzbekistan Academy of Science , 13. Okayama University of Science, 14. Hokkaido University, 15. Hokkaido University of Education, 16. Seoul National University Background & Aim: A numerical simulation proposes that the origin of near-Earth object 2007 MK6 (hereafter, MK6) is a near-Earth object (1566) Icarus (hereafter, Icarus) [1]. In addition to it, the orbital parameters of the daytime Taurid-Perseid meteor swarm are in good agreement with those of Icarus. Thus, it is considered that MK6 is split from the parent object Icarus by a rotational fission and/or an impact event, and the produced dust became to the daytime Taurid-Perseid meteor swarm. To confirm such a hypothesis, we need to obtain the observational evidence that the color indices of Icarus and MK6 are same. Moreover, if MK6 split by the rotational fission due to the YORP effect, the rotation period of Icarus would be shorten compared with the past rotation period. -
Non-Principal Axis Rotation (Tumbling) Asteroids
NON-PRINCIPAL AXIS ROTATION (TUMBLING) ASTEROIDS Asteroid PAR Per1 Amp1 Per2 Amp2 Reference 244 Sita T0 129.51 0.82 0 129.51 0.82 Brinsfield, 09 253 Mathilde T 417.7 0.50 –3 417.7 0.45 250. Mottola, 95 –3 418. 0.5 250. Pravec, 05 288 Glauke T 1170. 0.9 –1 1200. 0.9 Harris, 99 0 Pravec, 14 –2 1170. 0.37 740. Pilcher, 15 299∗ Thora T– 272.9 0.50 0 274. 0.39 Pilcher, 14 +2 272.9 0.47 Pilcher, 17 319∗ Leona T 430. 0.5 –2 430. 0.5 1084. Pilcher, 17 341∗ California T 318. 0.92 –2 318. 0.9 250. Pilcher, 17 –2 317.0 0.54 Polakis, 17 –1 317.0 0.92 Polakis, 17 408 Fama T0 202.1 0.58 0 202.1 0.58 Stephens, 08 470 Kilia T0 290. 0.26 0 290. 0.26 Stephens, 09 0 Stephens, 09 496∗ Gryphia T 1072. 1.25 –2 1072. 1.25 Pilcher, 17 571 Dulcinea T 126.3 0.50 –2 126.3 0.50 Stephens, 11 630 Euphemia T0 350. 0.45 0 350. 0.45 Warner, 11 703∗ No¨emi T? 200. 0.78 –1 201.7 0.78 Noschese, 17 0 115.108 0.28 Sada, 17 –2 200. 0.62 Franco, 17 707 Ste¨ına T0 414. 1.00 0 Pravec, 14 763∗ Cupido T 151.5 0.45 –1 151.1 0.24 Polakis, 18 –2 151.5 0.45 101. Pilcher, 18 823 Sisigambis T0 146. -
The Observer's Handbook for 1912
T he O bservers H andbook FOR 1912 PUBLISHED BY THE ROYAL ASTRONOMICAL SOCIETY OF CANADA E d i t e d b y C. A, CHANT FOURTH YEAR OF PUBLICATION TORONTO 198 C o l l e g e St r e e t Pr in t e d fo r t h e So c ie t y 1912 T he Observers Handbook for 1912 PUBLISHED BY THE ROYAL ASTRONOMICAL SOCIETY OF CANADA TORONTO 198 C o l l e g e St r e e t Pr in t e d fo r t h e S o c ie t y 1912 PREFACE Some changes have been made in the Handbook this year which, it is believed, will commend themselves to observers. In previous issues the times of sunrise and sunset have been given for a small number of selected places in the standard time of each place. On account of the arbitrary correction which must be made to the mean time of any place in order to get its standard time, the tables given for a particualar place are of little use any where else, In order to remedy this the times of sunrise and sunset have been calculated for places on five different latitudes covering the populous part of Canada, (pages 10 to 21), while the way to use these tables at a large number of towns and cities is explained on pages 8 and 9. The other chief change is in the addition of fuller star maps near the end. These are on a large enough scale to locate a star or planet or comet when its right ascension and declination are given. -
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. -
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. -
Download This Article in PDF Format
A&A 583, A85 (2015) Astronomy DOI: 10.1051/0004-6361/201526795 & c ESO 2015 Astrophysics Reaching the boundary between stellar kinematic groups and very wide binaries III. Sixteen new stars and eight new wide systems in the β Pictoris moving group F. J. Alonso-Floriano1, J. A. Caballero2, M. Cortés-Contreras1,E.Solano2,3, and D. Montes1 1 Departamento de Astrofísica y Ciencias de la Atmósfera, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain e-mail: [email protected] 2 Centro de Astrobiología (CSIC-INTA), ESAC PO box 78, 28691 Villanueva de la Cañada, Madrid, Spain 3 Spanish Virtual Observatory, ESAC PO box 78, 28691 Villanueva de la Cañada, Madrid, Spain Received 19 June 2015 / Accepted 8 August 2015 ABSTRACT Aims. We look for common proper motion companions to stars of the nearby young β Pictoris moving group. Methods. First, we compiled a list of 185 β Pictoris members and candidate members from 35 representative works. Next, we used the Aladin and STILTS virtual observatory tools and the PPMXL proper motion and Washington Double Star catalogues to look for companion candidates. The resulting potential companions were subjects of a dedicated astro-photometric follow-up using public data from all-sky surveys. After discarding 67 sources by proper motion and 31 by colour-magnitude diagrams, we obtained a final list of 36 common proper motion systems. The binding energy of two of them is perhaps too small to be considered physically bound. Results. Of the 36 pairs and multiple systems, eight are new, 16 have only one stellar component previously classified as a β Pictoris member, and three have secondaries at or below the hydrogen-burning limit. -
Asteroid 1566 Icarus's Size, Shape, Orbit, and Yarkovsky Drift from Radar
Draft version January 16, 2017 Preprint typeset using LATEX style emulateapj v. 5/2/11 ASTEROID 1566 ICARUS'S SIZE, SHAPE, ORBIT, AND YARKOVSKY DRIFT FROM RADAR OBSERVATIONS Adam H. Greenberg University of California, Los Angeles, CA Jean-Luc Margot University of California, Los Angeles, CA Ashok K. Verma University of California, Los Angeles, CA Patrick A. Taylor Arecibo Observatory, HC3 Box 53995, Arecibo, PR 00612, USA Shantanu P. Naidu Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA Marina. Brozovic Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA Lance A. M. Benner Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA Draft version January 16, 2017 ABSTRACT Near-Earth asteroid (NEA) 1566 Icarus (a = 1:08 au, e = 0:83, i = 22:8◦) made a close approach to Earth in June 2015 at 22 lunar distances (LD). Its detection during the 1968 approach (16 LD) was the first in the history of asteroid radar astronomy. A subsequent approach in 1996 (40 LD) did not yield radar images. We describe analyses of our 2015 radar observations of Icarus obtained at the Arecibo Observatory and the DSS-14 antenna at Goldstone. These data show that the asteroid is a moderately flattened spheroid with an equivalent diameter of 1.44 km with 18% uncertainties, resolving long-standing questions about the asteroid size. We also solve for Icarus' spin axis orientation (λ = 270◦ ± 10◦; β = −81◦ ± 10◦), which is not consistent with the estimates based on the 1968 lightcurve observations. Icarus has a strongly specular scattering behavior, among the highest ever measured in asteroid radar observations, and a radar albedo of ∼2%, among the lowest ever measured in asteroid radar observations. -
Ice & Stone 2020
Ice & Stone 2020 WEEK 12: MARCH 15-21, 2020 Presented by The Earthrise Institute # 12 Authored by Alan Hale the Earthrise Institute Simply stated, the mission of the Earthrise Institute is to use astronomy, space, and other related endeavors as a tool for breaking down international and intercultural barriers, and for bringing humanity together. The Earthrise Institute took its name from the images of Earth taken from lunar orbit by the Apollo astronauts. These images, which have captivated people from around the planet, show our Earth as one small, beautiful jewel in space, completely absent of any arbitrary political divisions or boundaries. They have provided new inspiration to protect what is right now the only home we have, and they encourage us to treat the other human beings who live on this planet as fellow residents and citizens of that home. They show, moreover, that we are all in this together, and that anything we do involves all of us. In that spirit, the Earthrise Institute has sought to preserve and enhance the ideals contained within the Earthrise images via a variety of activities. It is developing educational programs and curricula that utilize astronomical and space-related topics to teach younger generations and to lay the foundations so that they are in a position to create a positive future for humanity. Alan Hale Alan Hale began working at the Jet Propulsion Laboratory in Pasadena, California, as an engineering contractor for the Deep Space Network in 1983. While at JPL he was involved with several spacecraft projects, most notably the Voyager 2 encounter with the planet Uranus in 1986. -
On the Rotation Rates and Axis Ratios of the Smallest Known Near-Earth
On the rotation rates and axis ratios of the smallest known near-Earth asteroids—the archetypes of the Asteroid Redirect Mission targets Patrick Hatcha, Paul A. Wiegerta,b,∗ aDepartment of Physics and Astronomy, The University of Western Ontario, London, N6A 3K7 CANADA bCentre for Planetary Science and Exploration, The University of Western Ontario, London, N6A 3K7 CANADA Abstract NASA’s Asteroid Redirect Mission (ARM) has been proposed with the aim to capture a small asteroid a few meters in size and redirect it into an orbit around the Moon. There it can be investigated at leisure by astronauts aboard an Orion or other spacecraft. The target for the mission has not yet been selected, and there are very few potential targets currently known. Though sufficiently small near-Earth asteroids (NEAs) are thought to be numerous, they are also difficult to detect and characterize with current observational facilities. Here we collect the most up-to-date information on near-Earth asteroids in this size range to outline the state of understanding of the properties of these small NEAs. Observational biases certainly mean that our sample is not an ideal representation of the true population of small NEAs. However our sample is representative of the eventual target list for the ARM mission, which will be compiled under very similar observational constraints unless dramatic changes are made to the way near-Earth asteroids are searched for and studied. We collect here information on 88 near-Earth asteroids with diameters less than 60 meters and with high quality light curves. We find that the typical rotation period is 40 minutes. -
Radar Images Provide Details on Halloween Asteroid 4 November 2015
Radar images provide details on Halloween asteroid 4 November 2015 California, to transmit high-power microwaves toward the asteroid. The signal bounced off the asteroid, and its radar echoes were received by the National Radio Astronomy Observatory's (NRAO) 100-meter (330-foot) Green Bank Telescope in West Virginia. The radar images achieve a spatial resolution as fine as 13 feet (4 meters) per pixel. The radar images were taken as the asteroid flew past Earth on October 31 at 1 p.m. EDT at about 1.3 lunar distances (300,000 miles, or 480,000 kilometers) from Earth. Asteroid 2015 TB145 is spherical in shape and approximately 2,000 feet (600 meters) in diameter. "The radar images of asteroid 2015 TB145 show Asteroid 2015 TB145 is depicted in eight individual radar portions of the surface not seen previously and images collected on Oct. 31, 2015 between 5:55 a.m. PDT (8:55 a.m. EDT) and 6:08 a.m. PDT (9:08 a.m. reveal pronounced concavities, bright spots that EDT). At the time the radar images were taken, the might be boulders, and other complex features that asteroid was between 440,000 miles (710,000 could be ridges," said Lance Benner of NASA's Jet kilometers) and about 430,000 miles (690,000 Propulsion Laboratory in Pasadena, California, who kilometers) distant. Asteroid 2015 TB145 safely flew past leads NASA's asteroid radar research program. Earth on Oct. 31, at 10:00 a.m. PDT (1 p.m. EDT) at "The images look distinctly different from the about 1.3 lunar distances (300,000 miles, 480,000 Arecibo radar images obtained on October 30 and kilometers). -
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