Occultations with Video
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Astronomie in Theorie Und Praxis 8. Auflage in Zwei Bänden Erik Wischnewski
Astronomie in Theorie und Praxis 8. Auflage in zwei Bänden Erik Wischnewski Inhaltsverzeichnis 1 Beobachtungen mit bloßem Auge 37 Motivation 37 Hilfsmittel 38 Drehbare Sternkarte Bücher und Atlanten Kataloge Planetariumssoftware Elektronischer Almanach Sternkarten 39 2 Atmosphäre der Erde 49 Aufbau 49 Atmosphärische Fenster 51 Warum der Himmel blau ist? 52 Extinktion 52 Extinktionsgleichung Photometrie Refraktion 55 Szintillationsrauschen 56 Angaben zur Beobachtung 57 Durchsicht Himmelshelligkeit Luftunruhe Beispiel einer Notiz Taupunkt 59 Solar-terrestrische Beziehungen 60 Klassifizierung der Flares Korrelation zur Fleckenrelativzahl Luftleuchten 62 Polarlichter 63 Nachtleuchtende Wolken 64 Haloerscheinungen 67 Formen Häufigkeit Beobachtung Photographie Grüner Strahl 69 Zodiakallicht 71 Dämmerung 72 Definition Purpurlicht Gegendämmerung Venusgürtel Erdschattenbogen 3 Optische Teleskope 75 Fernrohrtypen 76 Refraktoren Reflektoren Fokus Optische Fehler 82 Farbfehler Kugelgestaltsfehler Bildfeldwölbung Koma Astigmatismus Verzeichnung Bildverzerrungen Helligkeitsinhomogenität Objektive 86 Linsenobjektive Spiegelobjektive Vergütung Optische Qualitätsprüfung RC-Wert RGB-Chromasietest Okulare 97 Zusatzoptiken 100 Barlow-Linse Shapley-Linse Flattener Spezialokulare Spektroskopie Herschel-Prisma Fabry-Pérot-Interferometer Vergrößerung 103 Welche Vergrößerung ist die Beste? Blickfeld 105 Lichtstärke 106 Kontrast Dämmerungszahl Auflösungsvermögen 108 Strehl-Zahl Luftunruhe (Seeing) 112 Tubusseeing Kuppelseeing Gebäudeseeing Montierungen 113 Nachführfehler -
Occultation Evidence for a Satellite of the Trojan Asteroid (911) Agamemnon Bradley Timerson1, John Brooks2, Steven Conard3, David W
Occultation Evidence for a Satellite of the Trojan Asteroid (911) Agamemnon Bradley Timerson1, John Brooks2, Steven Conard3, David W. Dunham4, David Herald5, Alin Tolea6, Franck Marchis7 1. International Occultation Timing Association (IOTA), 623 Bell Rd., Newark, NY, USA, [email protected] 2. IOTA, Stephens City, VA, USA, [email protected] 3. IOTA, Gamber, MD, USA, [email protected] 4. IOTA, KinetX, Inc., and Moscow Institute of Electronics and Mathematics of Higher School of Economics, per. Trekhsvyatitelskiy B., dom 3, 109028, Moscow, Russia, [email protected] 5. IOTA, Murrumbateman, NSW, Australia, [email protected] 6. IOTA, Forest Glen, MD, USA, [email protected] 7. Carl Sagan Center at the SETI Institute, 189 Bernardo Av, Mountain View CA 94043, USA, [email protected] Corresponding author Franck Marchis Carl Sagan Center at the SETI Institute 189 Bernardo Av Mountain View CA 94043 USA [email protected] 1 Keywords: Asteroids, Binary Asteroids, Trojan Asteroids, Occultation Abstract: On 2012 January 19, observers in the northeastern United States of America observed an occultation of 8.0-mag HIP 41337 star by the Jupiter-Trojan (911) Agamemnon, including one video recorded with a 36cm telescope that shows a deep brief secondary occultation that is likely due to a satellite, of about 5 km (most likely 3 to 10 km) across, at 278 km ±5 km (0.0931″) from the asteroid’s center as projected in the plane of the sky. A satellite this small and this close to the asteroid could not be resolved in the available VLT adaptive optics observations of Agamemnon recorded in 2003. -
Mathématiques Et Espace
Atelier disciplinaire AD 5 Mathématiques et Espace Anne-Cécile DHERS, Education Nationale (mathématiques) Peggy THILLET, Education Nationale (mathématiques) Yann BARSAMIAN, Education Nationale (mathématiques) Olivier BONNETON, Sciences - U (mathématiques) Cahier d'activités Activité 1 : L'HORIZON TERRESTRE ET SPATIAL Activité 2 : DENOMBREMENT D'ETOILES DANS LE CIEL ET L'UNIVERS Activité 3 : D'HIPPARCOS A BENFORD Activité 4 : OBSERVATION STATISTIQUE DES CRATERES LUNAIRES Activité 5 : DIAMETRE DES CRATERES D'IMPACT Activité 6 : LOI DE TITIUS-BODE Activité 7 : MODELISER UNE CONSTELLATION EN 3D Crédits photo : NASA / CNES L'HORIZON TERRESTRE ET SPATIAL (3 ème / 2 nde ) __________________________________________________ OBJECTIF : Détermination de la ligne d'horizon à une altitude donnée. COMPETENCES : ● Utilisation du théorème de Pythagore ● Utilisation de Google Earth pour évaluer des distances à vol d'oiseau ● Recherche personnelle de données REALISATION : Il s'agit ici de mettre en application le théorème de Pythagore mais avec une vision terrestre dans un premier temps suite à un questionnement de l'élève puis dans un second temps de réutiliser la même démarche dans le cadre spatial de la visibilité d'un satellite. Fiche élève ____________________________________________________________________________ 1. Victor Hugo a écrit dans Les Châtiments : "Les horizons aux horizons succèdent […] : on avance toujours, on n’arrive jamais ". Face à la mer, vous voyez l'horizon à perte de vue. Mais "est-ce loin, l'horizon ?". D'après toi, jusqu'à quelle distance peux-tu voir si le temps est clair ? Réponse 1 : " Sans instrument, je peux voir jusqu'à .................. km " Réponse 2 : " Avec une paire de jumelles, je peux voir jusqu'à ............... km " 2. Nous allons maintenant calculer à l'aide du théorème de Pythagore la ligne d'horizon pour une hauteur H donnée. -
On the Accuracy of Restricted Three-Body Models for the Trojan Motion
DISCRETE AND CONTINUOUS Website: http://AIMsciences.org DYNAMICAL SYSTEMS Volume 11, Number 4, December 2004 pp. 843{854 ON THE ACCURACY OF RESTRICTED THREE-BODY MODELS FOR THE TROJAN MOTION Frederic Gabern1, Angel` Jorba1 and Philippe Robutel2 Departament de Matem`aticaAplicada i An`alisi Universitat de Barcelona Gran Via 585, 08007 Barcelona, Spain1 Astronomie et Syst`emesDynamiques IMCCE-Observatoire de Paris 77 Av. Denfert-Rochereau, 75014 Paris, France2 Abstract. In this note we compare the frequencies of the motion of the Trojan asteroids in the Restricted Three-Body Problem (RTBP), the Elliptic Restricted Three-Body Problem (ERTBP) and the Outer Solar System (OSS) model. The RTBP and ERTBP are well-known academic models for the motion of these asteroids, and the OSS is the standard model used for realistic simulations. Our results are based on a systematic frequency analysis of the motion of these asteroids. The main conclusion is that both the RTBP and ERTBP are not very accurate models for the long-term dynamics, although the level of accuracy strongly depends on the selected asteroid. 1. Introduction. The Restricted Three-Body Problem models the motion of a particle under the gravitational attraction of two point masses following a (Keple- rian) solution of the two-body problem (a general reference is [17]). The goal of this note is to discuss the degree of accuracy of such a model to study the real motion of an asteroid moving near the Lagrangian points of the Sun-Jupiter system. To this end, we have considered two restricted three-body problems, namely: i) the Circular RTBP, in which Sun and Jupiter describe a circular orbit around their centre of mass, and ii) the Elliptic RTBP, in which Sun and Jupiter move on an elliptic orbit. -
HUBBLE ULTRAVIOLET SPECTROSCOPY of JUPITER TROJANS Ian Wong1†, Michael E
Draft version March 11, 2019 Preprint typeset using LATEX style emulateapj v. 12/16/11 HUBBLE ULTRAVIOLET SPECTROSCOPY OF JUPITER TROJANS Ian Wong1y, Michael E. Brown2, Jordana Blacksberg3, Bethany L. Ehlmann2,3, and Ahmed Mahjoub3 1Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; [email protected] 2Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 3Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA y51 Pegasi b Postdoctoral Fellow Draft version March 11, 2019 ABSTRACT We present the first ultraviolet spectra of Jupiter Trojans. These observations were carried out using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope and cover the wavelength range 200{550 nm at low resolution. The targets include objects from both of the Trojan color sub- populations (less-red and red). We do not observe any discernible absorption features in these spectra. Comparisons of the averaged UV spectra of less-red and red targets show that the subpopulations are spectrally distinct in the UV. Less-red objects display a steep UV slope and a rollover at around 450 nm to a shallower visible slope, whereas red objects show the opposite trend. Laboratory spectra of irradiated ices with and without H2S exhibit distinct UV absorption features; consequently, the featureless spectra observed here suggest H2S alone is not responsible for the observed color bimodal- ity of Trojans, as has been previously hypothesized. We propose some possible explanations for the observed UV-visible spectra, including complex organics, space weathering of iron-bearing silicates, and masked features due to previous cometary activity. -
Structure and Composition of the Surfaces of Trojan Asteroids from Reflection and Emission Spectroscopy
Lunar and Planetary Science XXXVII (2006) 2075.pdf STRUCTURE AND COMPOSITION OF THE SURFACES OF TROJAN ASTEROIDS FROM REFLECTION AND EMISSION SPECTROSCOPY. Joshua. P. Emery,1 Dale. P. Cruikshank,2 and Jeffrey Van Cleve3 1NASA Ames / SETI Institute ([email protected]), 2NASA Ames Research Center ([email protected]), 3 Ball Aerospace ([email protected]). Introduction: The orbits of Trojan asteroids (~5.2 AU – beyond the Main Belt) place them in the transi- 1.0 tion region between the rocky inner and icy outer Solar 0.9 1172 Aneas System. Most Trojans were traditionally thought to 0.8 have originated in this region [3], although other loca- 1.0 tions of origin are possible [e.g., 4,5,6]. Possible con- 0.9 nections between Trojans and other groups of objects 911 Agamemnon 0.8 (Jupiter family comets, irregular satellites, Centaurs, Emissivity KBOs) are also important, but only poorly understood 1.0 [4,6,7,9]. The compositions of Trojans thereby hold 0.9 624 Hektor important clues concerning conditions in this critical 0.8 transition region, and the solar nebula as a whole. We discuss emission and reflection spectra of three Trojans 10 15 20 25 30 35 Wavelength (µm) (624 Hektor, 911 Agamemnon, and 1172 Aneas) and implications for surface structure and composition. Figure 2. Mid-IR emissivity spectra of Trojans. Vis-NIR Reflectance Spectroscopy: Reflectance studies of Trojans in the visible and NIR (0.8 – 4.0 Analysis: The Trojans have a similar spectral shape µm) reveal dark surfaces with mild to very red spectral to some carbonaceous meteorites and fine-grained sili- slopes, but no distinct absorption features (Fig. -
Astrocladistics of the Jovian Trojan Swarms
MNRAS 000,1–26 (2020) Preprint 23 March 2021 Compiled using MNRAS LATEX style file v3.0 Astrocladistics of the Jovian Trojan Swarms Timothy R. Holt,1,2¢ Jonathan Horner,1 David Nesvorný,2 Rachel King,1 Marcel Popescu,3 Brad D. Carter,1 and Christopher C. E. Tylor,1 1Centre for Astrophysics, University of Southern Queensland, Toowoomba, QLD, Australia 2Department of Space Studies, Southwest Research Institute, Boulder, CO. USA. 3Astronomical Institute of the Romanian Academy, Bucharest, Romania. Accepted XXX. Received YYY; in original form ZZZ ABSTRACT The Jovian Trojans are two swarms of small objects that share Jupiter’s orbit, clustered around the leading and trailing Lagrange points, L4 and L5. In this work, we investigate the Jovian Trojan population using the technique of astrocladistics, an adaptation of the ‘tree of life’ approach used in biology. We combine colour data from WISE, SDSS, Gaia DR2 and MOVIS surveys with knowledge of the physical and orbital characteristics of the Trojans, to generate a classification tree composed of clans with distinctive characteristics. We identify 48 clans, indicating groups of objects that possibly share a common origin. Amongst these are several that contain members of the known collisional families, though our work identifies subtleties in that classification that bear future investigation. Our clans are often broken into subclans, and most can be grouped into 10 superclans, reflecting the hierarchical nature of the population. Outcomes from this project include the identification of several high priority objects for additional observations and as well as providing context for the objects to be visited by the forthcoming Lucy mission. -
The Brightest Stars Seite 1 Von 9
The Brightest Stars Seite 1 von 9 The Brightest Stars This is a list of the 300 brightest stars made using data from the Hipparcos catalogue. The stellar distances are only fairly accurate for stars well within 1000 light years. 1 2 3 4 5 6 7 8 9 10 11 12 13 No. Star Names Equatorial Galactic Spectral Vis Abs Prllx Err Dist Coordinates Coordinates Type Mag Mag ly RA Dec l° b° 1. Alpha Canis Majoris Sirius 06 45 -16.7 227.2 -8.9 A1V -1.44 1.45 379.21 1.58 9 2. Alpha Carinae Canopus 06 24 -52.7 261.2 -25.3 F0Ib -0.62 -5.53 10.43 0.53 310 3. Alpha Centauri Rigil Kentaurus 14 40 -60.8 315.8 -0.7 G2V+K1V -0.27 4.08 742.12 1.40 4 4. Alpha Boötis Arcturus 14 16 +19.2 15.2 +69.0 K2III -0.05 -0.31 88.85 0.74 37 5. Alpha Lyrae Vega 18 37 +38.8 67.5 +19.2 A0V 0.03 0.58 128.93 0.55 25 6. Alpha Aurigae Capella 05 17 +46.0 162.6 +4.6 G5III+G0III 0.08 -0.48 77.29 0.89 42 7. Beta Orionis Rigel 05 15 -8.2 209.3 -25.1 B8Ia 0.18 -6.69 4.22 0.81 770 8. Alpha Canis Minoris Procyon 07 39 +5.2 213.7 +13.0 F5IV-V 0.40 2.68 285.93 0.88 11 9. Alpha Eridani Achernar 01 38 -57.2 290.7 -58.8 B3V 0.45 -2.77 22.68 0.57 144 10. -
Anousheh Ansari
: Fort Worth Astronomical Society (Est. 1949) August 2010 Astronomical League Member At the August Meeting: Special Guest Anousheh Ansari Club Calendar – 2 – 3 Skyportunities Star Party & Club Reports – 5 House Calls by Ophiuchus – 6 Hubble’s Amazing Rescue – 8 Your Most Important Optics -- 9 Stargazers’ Diary – 11 1 Milky Way Over Colorado by Jim Murray August 2010 Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 7 Third Qtr Moon Challenge binary star for August: Make use of the New Viking 1 Orbiter 11:59 pm Moon Weekend for Alvan Clark 11 (ADS 11324) (Serpens Cauda) ceases operation better viewing at the 30 years ago Notable carbon star for August: Dark Sky Site Mars : Saturn O V Aquilae 1.9 Conjunction Mercury at greatest Challenge deep-sky object for August: eastern elongation Venus, Mars and Abell 53 (Aquila) Saturn all within a this evening binocular field of First in-flight New Moon view for the first 12 New Moon shuttle repair Neal Armstrong Weekend Weekend days of August. 15 years ago born 80 years ago 8 9 10 11 12 13 14 New Moon Moon at Perigee Double shadow (224,386 miles) transit on Jupiter 3RF Star Party 10:08 pm 1 pm 5:12am High in SSW Museum Star (A.T. @ 5:21 am) Party Venus : Saturn O . 3 of separation Perseid Meteor Watch Party @ 3RF New Moon Magellan enters Fairly consistent show Weekend orbit around Venus of about 60 per hour 20 years ago 15 16 17 18 19 20 21 Algol at Minima 2:45 am - In NE First Qtr Moon Total Solar 1:14 pm Eclipse in 7 years Nearest arc of totality takes in FWAS Grand Island NE St Joseph MO Meeting With Neptune @ Columbia MO Venus at greatest Opposition Anousheh Algol at Minima eastern elongation N of Nashville TN 11:34pm Low In NE 5 am N of Charleston SC Ansari this evening 22 23 24 25 26 27 28 Full Moon Moon at Apogee 2:05 pm (252,518.miles) GATE CODES Smallest of 2010 1 am to the (within 11 hrs of apogee) DARK SKY SITE will be changed st September 1 BE SURE YOU ARE CURRENT WITH DUES to Astroboy’s Day Job Venus : Mars receive new codes O 2 Conjunction 29 31 30 Anousheh Ansari’s Mission Patch at right. -
Tyson's Zodiac
Mercury Direct Mercury Tyson’s Zodiac: Are There Really Fourteen Signs? by Diana K. Rosenberg Dr. Neil deGrasse Tyson, research sci- chus treads upon the Scorpion (according entist in astrophysics at Princeton University to tradition) in order to crush it. (See Figure 1, and Curator of Astronomy at the Hayden Plan- page 60.) It is this overlap that creates a prob- etarium of the American Museum of Natural lem and makes it seem as though Ophiuchus’s History, has become a familiar face on tele- allotment of degrees exceeds the Scorpion’s. vision. He frequently appears on talk shows, Tyson wrote that the ecliptic stays in cheerily and with gusto declaiming that astrol- Ophiuchus for a longer period of time than in ogers are ignorant of the “fact” that there are Scorpius, but this holds true only if the artifi- fourteen zodiacal constellations, rather than cial demarcation lines imposed by the Inter- twelve. He has also authored several books, national Astronomical Union (IAU) in 1930 among them Universe Down to Earth. In this are adhered to.3 The astronomers who deter- work, he states: mined those lines could not bring themselves to accept overlaps or combinations; the lines, … the zodiac contains fourteen constella- they believed, must keep each figure entirely tions, not twelve. The Sun, after leaving the separate, and the sky figures, like caged ani- constellation Scorpius, enters the constella- mals, must remain within them.4 A quick tion Ophiuchus. It then stays in Ophiuchus glance at the lines dividing the Scorpion and for a longer [emphasis Tyson’s] period of the feet of Ophiuchus shows that absolutely no time than Scorpius, the sign that is adver- allowance was made for the Scorpion’s upper tised to precede Sagittarius. -
GTO Keypad Manual, V5.001
ASTRO-PHYSICS GTO KEYPAD Version v5.xxx Please read the manual even if you are familiar with previous keypad versions Flash RAM Updates Keypad Java updates can be accomplished through the Internet. Check our web site www.astro-physics.com/software-updates/ November 11, 2020 ASTRO-PHYSICS KEYPAD MANUAL FOR MACH2GTO Version 5.xxx November 11, 2020 ABOUT THIS MANUAL 4 REQUIREMENTS 5 What Mount Control Box Do I Need? 5 Can I Upgrade My Present Keypad? 5 GTO KEYPAD 6 Layout and Buttons of the Keypad 6 Vacuum Fluorescent Display 6 N-S-E-W Directional Buttons 6 STOP Button 6 <PREV and NEXT> Buttons 7 Number Buttons 7 GOTO Button 7 ± Button 7 MENU / ESC Button 7 RECAL and NEXT> Buttons Pressed Simultaneously 7 ENT Button 7 Retractable Hanger 7 Keypad Protector 8 Keypad Care and Warranty 8 Warranty 8 Keypad Battery for 512K Memory Boards 8 Cleaning Red Keypad Display 8 Temperature Ratings 8 Environmental Recommendation 8 GETTING STARTED – DO THIS AT HOME, IF POSSIBLE 9 Set Up your Mount and Cable Connections 9 Gather Basic Information 9 Enter Your Location, Time and Date 9 Set Up Your Mount in the Field 10 Polar Alignment 10 Mach2GTO Daytime Alignment Routine 10 KEYPAD START UP SEQUENCE FOR NEW SETUPS OR SETUP IN NEW LOCATION 11 Assemble Your Mount 11 Startup Sequence 11 Location 11 Select Existing Location 11 Set Up New Location 11 Date and Time 12 Additional Information 12 KEYPAD START UP SEQUENCE FOR MOUNTS USED AT THE SAME LOCATION WITHOUT A COMPUTER 13 KEYPAD START UP SEQUENCE FOR COMPUTER CONTROLLED MOUNTS 14 1 OBJECTS MENU – HAVE SOME FUN! -
Downloaded at %20Package.Zip
Data analysis of 2005 Regulus occultation and simulation of the 2014 occultation Costantino Sigismondi, ICRANet, UFRJ and Observatorio Nacional, Rio de Janeiro [email protected] Tony George, IOTA North America [email protected] Thomas Flatrès, IOTA European Section [email protected] Abstract On March 20, 2014 at 6:06 UT (2:06 New York time) Regulus, the 1.3 magnitude brighter star of Leo constellation, is going to be occulted by the asteroid 163 Erigone. The unusual event, visible to the naked eye over NYC, can allow to measure the shape of the asteroid, with reaching a space resolution below the diffraction limit of the eye, and of all instruments not based on interferometry. Ultimately the aperture of the instrument is related to the amount of scintillation affecting the light curve of the occultation, limitating the accuracy of video recorded data. The asteroid profile scans the surface of the star at a velocity of 6 mas/s; the diameter of the star is about 1.3 mas and the detection of the stellar limb darkening signature is discussed, taking into consideration also the Fresnel fringes. New data reduction with R-OTE software of the 2005 Regulus occultation and simulations of the 2014 occultation with Fren_difl software are presented. The occultation of Regulus of March 20, 2014 above New York City The total solar eclipse of 1925 above New York area [5] and the occultation of delta Ophiuchi above France and Germany in 2010 [4] have been two occultation events followed by a relatively high number of observers. Potentially the occultation of 1.3 mas [8] first magnitude star Regulus over New York City can be the first asteroidal occultation observed by million people and broadcasted on the internet [23].