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New Cases of Unusual Polarimetric Behavior in Asteroids
A&A 482, 309–314 (2008) Astronomy DOI: 10.1051/0004-6361:20078965 & c ESO 2008 Astrophysics New cases of unusual polarimetric behavior in asteroids R. Gil-Hutton1,2, V. Mesa2, A. Cellino3, P. Bendjoya4, L. Peñaloza2,andF.Lovos2 1 Complejo Astronómico El Leoncito – CONICET, Av. España 1512 sur, J5402DSP San Juan, Argentina e-mail: [email protected] 2 Universidad Nacional de San Juan, J. I. de la Roza 590 oeste, 5400 Rivadavia, San Juan, Argentina 3 INAF, Osservatorio Astronomico di Torino, 10025 Pino Torinese (TO), Italy 4 Laboratoire Fizeau, UMR 6525 Université Nice Sophia Antipolis , Observatoire de la Côte d’Azur, CNRS, 06108 Nice Cedex 2, France Received 30 October 2007 / Accepted 5 February 2008 ABSTRACT Aims. Results of different polarimetric campaigns at Complejo Astronómico El Leoncito (Casleo), San Juan, Argentina are presented. The aim of these campaigns was to search for objects exhibiting anomalous polarimetric properties, similar to those shown by the Ld-class asteroid (234) Barbara, among members of the same or similar taxonomic classes. Methods. The data have been obtained with Torino and CASPROF polarimeters at the 2.15 m telescope. The Torino polarimeter is an instrument that allows simultaneous measurement of polarization in five different bands, and CASPROF polarimeter is a two-hole aperture polarimeter with rapid modulation. Results. The campaigns began in 2005, and we found four new asteroids with Barbara-like polarimetric properties: the L-class objects (172) Baucis, (236) Honoria and (980) Anacostia, and the K-class asteroid (679) Pax. The polarimetric properties of the phase-polarization curves of these objects may be produced by a mixture of high- and low-albedo particles in their regolith as a result of the fragmentation of a substrate that is spectrally analog to the CO3/CV3 chondrites. -
107 Minor Planet Bulletin 37(2010) LIGHTCURVE PHOTOMETRY of 112 IPHIGENIA Stefan Cikota Physik-Institut, Universität Zürich, W
107 LIGHTCURVE PHOTOMETRY OF 112 IPHIGENIA Stefan Cikota Physik-Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, SWITZERLAND and Observatorio Astronomico de Mallorca 07144 Costitx, Mallorca, Illes Balears, SPAIN [email protected] Aleksandar Cikota Physik-Institut, Universität Zürich, CH-8057 Zürich, SWITZERLAND and Observatorio Astronomico de Mallorca MINOR PLANET LIGHTCURVE ANALYSIS OF 07144 Costitx, Mallorca, Illes Balears, SPAIN 347 PARIANA AND 6560 PRAVDO (Received: 19 March) Peter Caspari BDI Observatory PO Box 194 Regents Park The main-belt asteroid 112 Iphigenia was observed over NSW 2143, AUSTRALIA 6 nights between 2007 December 9 and December 14 at [email protected] the Observatorio Astronomico de Mallorca (620). From the resulting data, we determined a synodic rotation (Received: 15 January Revised: 22 February) period of 31.385 ± 0.006 h and lightcurve amplitude of 0.30 ± 0.02 mag. Minor planet 347 Pariana was observed in 2009 July and again in 2009 August and September resulting in two 122 Iphigenia was tracked over 6 nights between 2007 December complete lightcurves both with a rotational period 9 and December 14 with one, and sometimes two, identical estimate of 4.052 ± 0.002 h and amplitude of 0.5 mag. telescopes (0.30-m f/9 Schmidt-Cassegrain) located at the These data were combined with data from previous Observatorio Astronomico de Mallorca in Spain. Both were apparitions to produce estimates for a sidereal period, equipped with an SBIG STL-1001E CCD camera. Image spin axis, and shape model. Minor planet 6560 Pravdo acquisition and calibration were performed using Maxim DL. All was observed over nine nights in 2009 June and July 1593 images were unfiltered and had exposures of 60 seconds. -
Gamma Ray Bursts (Grbs)
15 Epilogue Roger D. Blandford Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305, USA The preceding fourteen chapters have been written at a good time to take stock of the field of Gamma Ray Bursts (GRBs). The extraordinary discov- eries made over the last decade or so about a phenomenon that has been around for over four decades seem to have attained a mature state. Thou- sands of bursts have been observed, classified and followed up and it is now the special and rare cases, that are extreme by some important measure, that are most likely to advance our understanding as radically new γ−ray and X-ray observing capabilities are at least a decade away. On the theoret- ical front, some prescient inferences have been vindicated, phenomenological models that are usable by observers have been developed, and simulation has made great strides. The greatest challenge is to explore the underlying physical processes in much more detail and this is likely to require a new generation of high performance computers. Nonetheless, the GRB pace of discovery like much of contemporary astrophysics will likely exceed that in most other subfields of physical science. I was asked to write a critique of where we are today and what I think will be the major developments going forward. My qualifications for this task are not promising. I have probably contributed most to the study of a high energy γ−ray stellar phenomenon unintentionally in the context of trying to explain variability of the lowest frequency radio emission from active galaxies and my largest attempt to work on what I thought was relevant turned out to be only applicable, at best, to X-ray bursting neutron stars. -
Guide to the Extended Versions of MPC Data Files Based on the MPCORB Format
Guide to the Extended Versions of MPC Data Files Based on the MPCORB Format Last updated: 2016/04/19 by J.L. Galache Introduction The Minor Planet Center (MPC) has been providing the orbits of minor planets in the form of a file, MPCORB.DAT, since the mid '90s (1990s, not 1890s). Back then there were only a few thousand known asteroids, compared to the several hundred thousand of today, so a flat text file was the appropriate way to circulate these data. It was also a time when most orbit computations were programmed in Fortran, which ingested data no other way. MPCORB.DAT has therefore always been, and continues to be, a fixed-width file (see Table 1 for the current format description1). In fact, all original data files available on the MPC website are flat text files (even the orbits files provided for planetarium-type/sky simulation software packages are simply text files of varying format2). In the early years of the 2010s, possibly due to the rising popularity of the scripting language Python amongst astronomers, and an increased interest from developers wanting to write asteroid-themed tools, requests were received to provide data in other, easier to parse formats, e.g., JSON, CSV, SQL, etc. At the same time, astronomers and developers alike wanted more information than was currently been provided in MPCORB.DAT; information that did exist on the MPC website in other, often hard to find, files. Here was an opportunity to add some new data to existing files, while also making them available in other formats. -
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. -
An Ancient and a Primordial Collisional Family As the Main Sources of X-Type Asteroids of the Inner Main Belt
Astronomy & Astrophysics manuscript no. agapi2019.01.22_R1 c ESO 2019 February 6, 2019 An ancient and a primordial collisional family as the main sources of X-type asteroids of the inner Main Belt ∗ Marco Delbo’1, Chrysa Avdellidou1; 2, and Alessandro Morbidelli1 1 Université Côte d’Azur, CNRS–Lagrange, Observatoire de la Côte d’Azur, CS 34229 – F 06304 NICE Cedex 4, France e-mail: [email protected] e-mail: [email protected] 2 Science Support Office, Directorate of Science, European Space Agency, Keplerlaan 1, NL-2201 AZ Noordwijk ZH, The Netherlands. Received February 6, 2019; accepted February 6, 2019 ABSTRACT Aims. The near-Earth asteroid population suggests the existence of an inner Main Belt source of asteroids that belongs to the spec- troscopic X-complex and has moderate albedos. The identification of such a source has been lacking so far. We argue that the most probable source is one or more collisional asteroid families that escaped discovery up to now. Methods. We apply a novel method to search for asteroid families in the inner Main Belt population of asteroids belonging to the X- complex with moderate albedo. Instead of searching for asteroid clusters in orbital elements space, which could be severely dispersed when older than some billions of years, our method looks for correlations between the orbital semimajor axis and the inverse size of asteroids. This correlation is the signature of members of collisional families, which drifted from a common centre under the effect of the Yarkovsky thermal effect. Results. We identify two previously unknown families in the inner Main Belt among the moderate-albedo X-complex asteroids. -
76 Minor Planet Bulletin 45 (2018) TWENTY-ONE ASTEROID LIGHTCURVES at ASTEROIDS OBSERVERS (OBAS)
76 TWENTY-ONE ASTEROID LIGHTCURVES needed confirmation. All the targets were selected from the AT ASTEROIDS OBSERVERS (OBAS) - MPPD: Collaborative Asteroid Lightcurve (CALL) website at NOV 2016 - MAY 2017 http://www.minorplanet.info/call.html, paying special attention to keeping the asteroid’s magnitude within reach of the telescopes Vicente Mas, G. Fornas being used. We tried to observe asteroids at a phase angle of less CAAT, Centro Astronómico del Alto Turia, SPAIN than 14°, but this was not always possible. [email protected] Images were measured using MPO Canopus (Bdw Publishing) Juan Lozano with a differential photometry technique. For more information Elche Observatory, Alicante, SPAIN about methods and techniques used, see Aznar Macias et al. (2015). Table II lists the individual results along with the range of Onofre Rodrigo dates for the observations and the number of nights that Bétera Observatory, Valencia, SPAIN observations were made. A. Fornas 589 Croatia, Observed on nine nights from 2016 Nov to 2017 Jan. Oropesa Observatory, Castellón, SPAIN Period: 24.73 ± 0.013 h. Amplitude: 0.47 mag. This result is consistent with Behrend (2013), who found 24.821 h, but not with A. Carreño Waszczak et al. (2015) who found 16.385 h. Zonalunar Observatory,Valencia, SPAIN 593 Titania. Observed during five nights 2017 Apr. Period: 9.930 Enrique Arce ± 0.009 h. Amplitude: 0.21 mag. This period is consistent with Vallbona Observatory, Valencia, SPAIN Zappala (1983, 9.89 h), Harris (1989, 9.899 h), and Behrend (2017, 9.8968 h). Pedro Brines TRZ Observatory, Valencia, SPAIN 728 Leonisis. Observed on two nights in 2017 March-April. -
The Minor Planet Bulletin 37 (2010) 45 Classification for 244 Sita
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 37, NUMBER 2, A.D. 2010 APRIL-JUNE 41. LIGHTCURVE AND PHASE CURVE OF 1130 SKULD Robinson (2009) from his data taken in 2002. There is no evidence of any change of (V-R) color with asteroid rotation. Robert K. Buchheim Altimira Observatory As a result of the relatively short period of this lightcurve, every 18 Altimira, Coto de Caza, CA 92679 (USA) night provided at least one minimum and maximum of the [email protected] lightcurve. The phase curve was determined by polling both the maximum and minimum points of each night’s lightcurve. Since (Received: 29 December) The lightcurve period of asteroid 1130 Skuld is confirmed to be P = 4.807 ± 0.002 h. Its phase curve is well-matched by a slope parameter G = 0.25 ±0.01 The 2009 October-November apparition of asteroid 1130 Skuld presented an excellent opportunity to measure its phase curve to very small solar phase angles. I devoted 13 nights over a two- month period to gathering photometric data on the object, over which time the solar phase angle ranged from α = 0.3 deg to α = 17.6 deg. All observations used Altimira Observatory’s 0.28-m Schmidt-Cassegrain telescope (SCT) working at f/6.3, SBIG ST- 8XE NABG CCD camera, and photometric V- and R-band filters. Exposure durations were 3 or 4 minutes with the SNR > 100 in all images, which were reduced with flat and dark frames. -
Strange and Terrible Wonders: Climate Change In
STRANGE AND TERRIBLE WONDERS: CLIMATE CHANGE IN THE EARLY MODERN WORLD A Dissertation by CHRISTOPHER RYAN GILSON Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Chester S. L. Dunning Committee Members, R. J. Q. Adams Joseph G. Dawson III Peter J. Hugill Head of Department, David Vaught August 2015 Major Subject: History Copyright 2015 Christopher R. Gilson ABSTRACT The study of climate and climatic change began during the Little Ice Age of the early modern world. Beginning in the sixteenth century, European clerics, scientists, and natural philosophers penned detailed observations of the era’s unusually cool and stormy weather. Scouring the historical record for evidence of similar phenomena in the past, early modern scholars concluded that the climate could change. By the eighteenth century, natural philosophers had identified at least five theories of climatic change, and many had adopted some variation of an anthropogenic explanation. The early modern observations described in this dissertation support the conclusion that cool temperatures and violent storms defined the Little Ice Age. This dissertation also demonstrates that modern notions of climate change are based upon 400 years of rich scholarship and spirited debate. This dissertation opens with a discussion of the origins of “climate” and meteorology in ancient Greek and Roman literature, particularly Aristotle’s Meteorologica. Although ancient scholars explored notions of environmental change, climate change—defined as such—was thought impossible. The translation and publication of ancient texts during the Renaissance contributed to the reexamination of nature and natural variability. -
The Minor Planet Bulletin
THE MINOR PLANET BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS VOLUME 35, NUMBER 3, A.D. 2008 JULY-SEPTEMBER 95. ASTEROID LIGHTCURVE ANALYSIS AT SCT/ST-9E, or 0.35m SCT/STL-1001E. Depending on the THE PALMER DIVIDE OBSERVATORY: binning used, the scale for the images ranged from 1.2-2.5 DECEMBER 2007 – MARCH 2008 arcseconds/pixel. Exposure times were 90–240 s. Most observations were made with no filter. On occasion, e.g., when a Brian D. Warner nearly full moon was present, an R filter was used to decrease the Palmer Divide Observatory/Space Science Institute sky background noise. Guiding was used in almost all cases. 17995 Bakers Farm Rd., Colorado Springs, CO 80908 [email protected] All images were measured using MPO Canopus, which employs differential aperture photometry to determine the values used for (Received: 6 March) analysis. Period analysis was also done using MPO Canopus, which incorporates the Fourier analysis algorithm developed by Harris (1989). Lightcurves for 17 asteroids were obtained at the Palmer Divide Observatory from December 2007 to early The results are summarized in the table below, as are individual March 2008: 793 Arizona, 1092 Lilium, 2093 plots. The data and curves are presented without comment except Genichesk, 3086 Kalbaugh, 4859 Fraknoi, 5806 when warranted. Column 3 gives the full range of dates of Archieroy, 6296 Cleveland, 6310 Jankonke, 6384 observations; column 4 gives the number of data points used in the Kervin, (7283) 1989 TX15, 7560 Spudis, (7579) 1990 analysis. Column 5 gives the range of phase angles. -
(K)Cudos at Ψtucson
(K)CUDOs at ΨTucson Work based on collaborative effort with present/former AZ students: Jeremiah Birrell and Lance Labun with contributions from exchange student from Germany Ch. Dietl. Johann Rafelski (UA-Physics) (K)CUDOS at ΨTucson PSITucson,April11,2013 1/39 1. Introduction 2. Dark Matter (CDM) Generalities 3. Strangeletts 4. Dark Matter (DM) CUDOs 5. CUDO impacts Johann Rafelski (UA-Physics) (K)CUDOS at ΨTucson PSITucson,April11,2013 2/39 kudos (from Greek kyddos, singular) = honor; glory; acclaim; praise kudo = back formation from kudos construed as a plural cud (Polish, pronounced c-ood) = miracle cudo (colloq. Polish) = of surprising and exceptional character CUDO=Compact UltraDense Object: A new opportunity to search for dark matter. Not dark matter in form of elementary particles (all present day searches) but (self) bound dark matter. Either an ultra-compact impactor or/and condensation seed for comets. There is a lot of dark matter around, cosmological abundance limit shown below. Johann Rafelski (UA-Physics) (K)CUDOS at ΨTucson PSITucson,April11,2013 3/39 A new type of meteors What if there are ‘dark’ matter meteor and asteroid-like bodies in the Universe? Could some of them have collided with solar system bodies and the Earth? Are they dressed in visible matter from prior impacts and as condensation seeds? CUDOs’ high density of gravitating matter provides the distinct observable, the surface-penetrating puncture: shot through Only a fraction of the kinetic energy damaging the solid surface. Johann Rafelski (UA-Physics) (K)CUDOS at ΨTucson PSITucson,April11,2013 4/39 Asteroids of high density Fruitful Discussions with Marshall Eubanks lead to these data. -
Asteroid Observations at Low Phase Angles. IV. Average Parameters for the New H, G1, G2 Magnitude System Vasilij G
Planetary and Space Science ∎ (∎∎∎∎) ∎∎∎–∎∎∎ Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss Asteroid observations at low phase angles. IV. Average parameters for the new H, G1, G2 magnitude system Vasilij G. Shevchenko a,b,n, Irina N. Belskaya a, Karri Muinonen c,d, Antti Penttilä c, Yurij N. Krugly a, Feodor P. Velichko a, Vasilij G. Chiorny a, Ivan G. Slyusarev a,b, Ninel M. Gaftonyuk e, Igor A. Tereschenko a a Institute of Astronomy of Kharkiv Karazin National University, Sumska str. 35, Kharkiv 61022, Ukraine b Department of Astronomy and Space Informatics of Kharkiv Karazin National University, Svobody sqr. 4, Kharkiv 61022, Ukraine c Department of Physics, University of Helsinki, P.O. Box 64, FI-00014, Finland d Finnish Geospatial Research Institute, P.O. Box 15, Masala, FI-02431, Finland e Crimean Astrophysical Observatory, Crimea, Simeiz 98680, Ukraine article info abstract Article history: We present new observational data for selected main-belt asteroids of different compositional types. The Received 21 January 2015 detailed magnitude–phase dependences including small phase angles (o1°) were obtained for these Received in revised form asteroids, namely: (10) Hygiea (down to the phase angle of 0.3°, C-type), (176) Iduna (0.2°, G-type), (214) 6 September 2015 Aschera (0.2°, E-type), (218) Bianca (0.3°, S-type), (250) Bettina (0.3°, M-type), (419) Aurelia (0.1°, F-type), Accepted 19 November 2015 (596) Scheila (0.2°, D-type), (635) Vundtia (0.2°, B-type), (671) Carnegia (0.2°, P-type), (717) Wisibada (0.1°, T-type), (1021) Flammario (0.6°, B-type), and (1279) Uganda (0.5°, E-type).