Jun 2016 Newsletter
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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. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Inclination Evolution of Protoplanetary Disks Around Eccentric Binaries
Mon. Not. R. Astron. Soc. 000, 000{000 (0000) Printed 11 October 2017 (MN LATEX style file v2.2) Inclination Evolution of Protoplanetary Disks Around Eccentric Binaries J. J. Zanazzi1?, and Dong Lai1 1Cornell Center for Astrophysics, Planetary Science, Department of Astronomy, Cornell University, Ithaca, NY 14853, USA 11 October 2017 ABSTRACT It is usually thought that viscous torque works to align a circumbinary disk with the binary's orbital plane. However, recent numerical simulations suggest that the disk may evolve to a configuration perpendicular to the binary orbit (\polar alignment") if the binary is eccentric and the initial disk-binary inclination is sufficiently large. We carry out a theoretical study on the long-term evolution of inclined disks around eccentric binaries, calculating the disk warp profile and dissipative torque acting on the disk. For disks with aspect ratio H=r larger than the viscosity parameter α, bend- ing wave propagation effectively makes the disk precess as a quasi-rigid body, while viscosity acts on the disk warp and twist to drive secular evolution of the disk-binary inclination. We derive a simple analytic criterion (in terms of the binary eccentricity and initial disk orientation) for the disk to evolve toward polar alignment with the eccentric binary. When the disk has a non-negligible angular momentum compared to the binary, the final \polar alignment" inclination angle is reduced from 90◦. For typical protoplanetary disk parameters, the timescale of the inclination evolution is shorter than the disk lifetime, suggesting that highly-inclined disks and planets may exist orbiting eccentric binaries. Key words: Physical data and processes: accretion, accretion discs; Physical data and processes: hydrodynamics; stars: binaries: general; protoplanetary discs. -
Planets Transiting Non-Eclipsing Binaries
A&A 570, A91 (2014) Astronomy DOI: 10.1051/0004-6361/201323112 & c ESO 2014 Astrophysics Planets transiting non-eclipsing binaries David V. Martin1 and Amaury H. M. J. Triaud2;? 1 Observatoire Astronomique de l’Université de Genève, Chemin des Maillettes 51, CH-1290 Sauverny, Switzerland e-mail: [email protected] 2 Kavli Institute for Astrophysics & Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA Received 22 November 2013 / Accepted 28 August 2014 ABSTRACT The majority of binary stars do not eclipse. Current searches for transiting circumbinary planets concentrate on eclipsing binaries, and are therefore restricted to a small fraction of potential hosts. We investigate the concept of finding planets transiting non-eclipsing binaries, whose geometry would require mutually inclined planes. Using an N-body code we explore how the number and sequence of transits vary as functions of observing time and orbital parameters. The concept is then generalised thanks to a suite of simulated circumbinary systems. Binaries are constructed from radial-velocity surveys of the solar neighbourhood. They are then populated with orbiting gas giants, drawn from a range of distributions. The binary population is shown to be compatible with the Kepler eclipsing binary catalogue, indicating that the properties of binaries may be as universal as the initial mass function. These synthetic systems produce transiting circumbinary planets occurring on both eclipsing and non-eclipsing binaries. Simulated planets transiting eclipsing binaries are compared with published Kepler detections. We find 1) that planets transiting non-eclipsing binaries are probably present in the Kepler data; 2) that observational biases alone cannot account for the observed over-density of circumbinary planets near the stability limit, which implies a physical pile-up; and 3) that the distributions of gas giants orbiting single and binary stars are likely different. -
NEWSLETTER August 2015
NEWSLETTER August 2015 New Horizons at Pluto Credit NASA This space is reserved for promoting member's businesses. You can place an advert here for a donation to the group. Issue 11 August 2015 Page 1 Contents Cover 1 Contents 2 About the cover picture New Horizons 3-7 Thanet Astronomy Group Contact Details 8 Member's Meeting Dates and Times 9 Advertisement (West Bay Cafe) 10 What we did last month 11 Junior Members Page 12 Advertisement (Renaissance Glass) 13 Book Review 14 What's in the sky this month 15-17 Member's Page 18-19 Did You Know ? 20 Junior Astronomers Club (JAC & Gill) 21 Executive Committee Messages 22 Adult Word Search 23 Junior Word Search 24 Member's For Sale and Wanted 25 Issue 11 August 2015 Page 2 About the Cover Picture NEW HORIZONS New Horizons at Pluto Credit NASA New Horizons The Mission The New Horizons mission is the first mission to Pluto and the Kuiper Belt This mission has sent a space craft to the outer reaches of our Solar System to look at the dwarf planet Pluto, and beyond into the Kuiper Belt. The Kuiper Belt is the region of our Solar System beyond the orbit of the planet Neptune, about 30 Astronomical Units (AU) from the Sun and out to about 50 AU. This region contains the minor planet Pluto and its moons Charon, Hydra, Nix and Styx along with many comets, asteroids and many other small objects mostly made of ice. The Kuiper Belt - Credit: NASA Issue 11 August 2015 Page 3 About the Cover Picture NEW HORIZONS An AU or Astronomical Unit is equal to the distance between the Sun and the Earth about 93,000,000 miles or 150,000,000 km. -
FIXED STARS a SOLAR WRITER REPORT for Churchill Winston WRITTEN by DIANA K ROSENBERG Page 2
FIXED STARS A SOLAR WRITER REPORT for Churchill Winston WRITTEN BY DIANA K ROSENBERG Page 2 Prepared by Cafe Astrology cafeastrology.com Page 23 Churchill Winston Natal Chart Nov 30 1874 1:30 am GMT +0:00 Blenhein Castle 51°N48' 001°W22' 29°‚ 53' Tropical ƒ Placidus 02' 23° „ Ý 06° 46' Á ¿ 21° 15° Ý 06' „ 25' 23° 13' Œ À ¶29° Œ 28° … „ Ü É Ü 06° 36' 26' 25° 43' Œ 51'Ü áá Œ 29° ’ 29° “ àà … ‘ à ‹ – 55' á á 55' á †32' 16° 34' ¼ † 23° 51'Œ 23° ½ † 06' 25° “ ’ † Ê ’ ‹ 43' 35' 35' 06° ‡ Š 17° 43' Œ 09° º ˆ 01' 01' 07° ˆ ‰ ¾ 23° 22° 08° 02' ‡ ¸ Š 46' » Ï 06° 29°ˆ 53' ‰ Page 234 Astrological Summary Chart Point Positions: Churchill Winston Planet Sign Position House Comment The Moon Leo 29°Le36' 11th The Sun Sagittarius 7°Sg43' 3rd Mercury Scorpio 17°Sc35' 2nd Venus Sagittarius 22°Sg01' 3rd Mars Libra 16°Li32' 1st Jupiter Libra 23°Li34' 1st Saturn Aquarius 9°Aq35' 5th Uranus Leo 15°Le13' 11th Neptune Aries 28°Ar26' 8th Pluto Taurus 21°Ta25' 8th The North Node Aries 25°Ar51' 8th The South Node Libra 25°Li51' 2nd The Ascendant Virgo 29°Vi55' 1st The Midheaven Gemini 29°Ge53' 10th The Part of Fortune Capricorn 8°Cp01' 4th Chart Point Aspects Planet Aspect Planet Orb App/Sep The Moon Semisquare Mars 1°56' Applying The Moon Trine Neptune 1°10' Separating The Moon Trine The North Node 3°45' Separating The Moon Sextile The Midheaven 0°17' Applying The Sun Semisquare Jupiter 0°50' Applying The Sun Sextile Saturn 1°52' Applying The Sun Trine Uranus 7°30' Applying Mercury Square Uranus 2°21' Separating Mercury Opposition Pluto 3°49' Applying Venus Sextile -
Binocular Double Star Logbook
Astronomical League Binocular Double Star Club Logbook 1 Table of Contents Alpha Cassiopeiae 3 14 Canis Minoris Sh 251 (Oph) Psi 1 Piscium* F Hydrae Psi 1 & 2 Draconis* 37 Ceti Iota Cancri* 10 Σ2273 (Dra) Phi Cassiopeiae 27 Hydrae 40 & 41 Draconis* 93 (Rho) & 94 Piscium Tau 1 Hydrae 67 Ophiuchi 17 Chi Ceti 35 & 36 (Zeta) Leonis 39 Draconis 56 Andromedae 4 42 Leonis Minoris Epsilon 1 & 2 Lyrae* (U) 14 Arietis Σ1474 (Hya) Zeta 1 & 2 Lyrae* 59 Andromedae Alpha Ursae Majoris 11 Beta Lyrae* 15 Trianguli Delta Leonis Delta 1 & 2 Lyrae 33 Arietis 83 Leonis Theta Serpentis* 18 19 Tauri Tau Leonis 15 Aquilae 21 & 22 Tauri 5 93 Leonis OΣΣ178 (Aql) Eta Tauri 65 Ursae Majoris 28 Aquilae Phi Tauri 67 Ursae Majoris 12 6 (Alpha) & 8 Vul 62 Tauri 12 Comae Berenices Beta Cygni* Kappa 1 & 2 Tauri 17 Comae Berenices Epsilon Sagittae 19 Theta 1 & 2 Tauri 5 (Kappa) & 6 Draconis 54 Sagittarii 57 Persei 6 32 Camelopardalis* 16 Cygni 88 Tauri Σ1740 (Vir) 57 Aquilae Sigma 1 & 2 Tauri 79 (Zeta) & 80 Ursae Maj* 13 15 Sagittae Tau Tauri 70 Virginis Theta Sagittae 62 Eridani Iota Bootis* O1 (30 & 31) Cyg* 20 Beta Camelopardalis Σ1850 (Boo) 29 Cygni 11 & 12 Camelopardalis 7 Alpha Librae* Alpha 1 & 2 Capricorni* Delta Orionis* Delta Bootis* Beta 1 & 2 Capricorni* 42 & 45 Orionis Mu 1 & 2 Bootis* 14 75 Draconis Theta 2 Orionis* Omega 1 & 2 Scorpii Rho Capricorni Gamma Leporis* Kappa Herculis Omicron Capricorni 21 35 Camelopardalis ?? Nu Scorpii S 752 (Delphinus) 5 Lyncis 8 Nu 1 & 2 Coronae Borealis 48 Cygni Nu Geminorum Rho Ophiuchi 61 Cygni* 20 Geminorum 16 & 17 Draconis* 15 5 (Gamma) & 6 Equulei Zeta Geminorum 36 & 37 Herculis 79 Cygni h 3945 (CMa) Mu 1 & 2 Scorpii Mu Cygni 22 19 Lyncis* Zeta 1 & 2 Scorpii Epsilon Pegasi* Eta Canis Majoris 9 Σ133 (Her) Pi 1 & 2 Pegasi Δ 47 (CMa) 36 Ophiuchi* 33 Pegasi 64 & 65 Geminorum Nu 1 & 2 Draconis* 16 35 Pegasi Knt 4 (Pup) 53 Ophiuchi Delta Cephei* (U) The 28 stars with asterisks are also required for the regular AL Double Star Club. -
Solar Writer Report for Abraham Lincoln
FIXED STARS A Solar Writer Report for Abraham Lincoln Written by Diana K Rosenberg Compliments of:- Stephanie Johnson Seeing With Stars Astrology PO Box 159 Stepney SA 5069 Australia Tel/Fax: +61 (08) 8331 3057 Email: [email protected] Web: www.esotech.com.au Page 2 Abraham Lincoln Natal Chart 12 Feb 1809 12:40:56 PM UT +0:00 near Hodgenville 37°N35' 085°W45' Tropical Placidus 22' 13° 08°ˆ ‡ 17' ¾ 06' À ¿É ‰ 03° ¼ 09° 00° 06° 09°06° ˆ ˆ ‡ † ‡ 25° 16' 41'08' 40' † 01' 09' Œ 29' ‰ 9 10 23° ¶ 8 27°‰ 11 Ï 27° 01' ‘ ‰02' á 7 12 ‘ áá 23° á 23° ¸ 23°Š27' á Š à „ 28' 28' 6 18' 1 10°‹ º ‹37' 13° 05' ‹ 5 Á 22° ½ 27' 2 4 01' Ü 3 07° Œ ƒ » 09' 23° 09° Ý Ü 06° 16' 06' Ê 00°ƒ 13° 22' Ý 17' 08°‚ Page 23 Astrological Summary Chart Point Positions: Abraham Lincoln Planet Sign Position House Comment The Moon Capricorn 27°Cp01' 12th The Sun Aquarius 23°Aq27' 12th read into 1st House Mercury Pisces 10°Pi18' 1st Venus Aries 7°Ar27' 1st read into 2nd House Mars Libra 25°Li29' 8th Jupiter Pisces 22°Pi05' 1st Saturn Sagittarius 3°Sg08' 9th read into 10th House Uranus Scorpio 9°Sc40' 8th Neptune Sagittarius 6°Sg41' 9th read into 10th House Pluto Pisces 13°Pi37' 1st The North Node Scorpio 6°Sc09' 8th The South Node Taurus 6°Ta09' 2nd The Ascendant Aquarius 23°Aq28' 1st The Midheaven Sagittarius 8°Sg22' 10th The Part of Fortune Capricorn 27°Cp02' 12th Chart Point Aspects Planet Aspect Planet Orb App/Sep The Moon Square Mars 1°32' Separating The Moon Conjunction The Part of Fortune 0°00' Applying The Sun Trine Mars 2°02' Applying The Sun Conjunction The Ascendant -
Dark Matter Thermonuclear Supernova Ignition
MNRAS 000,1{21 (2019) Preprint 1 January 2020 Compiled using MNRAS LATEX style file v3.0 Dark Matter Thermonuclear Supernova Ignition Heinrich Steigerwald,1? Stefano Profumo,2 Davi Rodrigues,1 Valerio Marra1 1Center for Astrophysics and Cosmology (Cosmo-ufes) & Department of Physics, Federal University of Esp´ırito Santo, Vit´oria, ES, Brazil 2Department of Physics and Santa Cruz Institute for Particle Physics, 1156 High St, University of California, Santa Cruz, CA 95064, USA Accepted XXX. Received YYY; in original form ZZZ ABSTRACT We investigate local environmental effects from dark matter (DM) on thermonuclear supernovae (SNe Ia) using publicly available archival data of 224 low-redshift events, in an attempt to shed light on the SN Ia progenitor systems. SNe Ia are explosions of carbon-oxygen (CO) white dwarfs (WDs) that have recently been shown to explode at sub-Chandrasekhar masses; the ignition mechanism remains, however, unknown. Recently, it has been shown that both weakly interacting massive particles (WIMPs) and macroscopic DM candidates such as primordial black holes (PBHs) are capable of triggering the ignition. Here, we present a method to estimate the DM density and velocity dispersion in the vicinity of SN Ia events and nearby WDs; we argue that (i) WIMP ignition is highly unlikely, and that (ii) DM in the form of PBHs distributed according to a (quasi-) log-normal mass distribution with peak log10¹m0/1gº = 24:9±0:9 and width σ = 3:3 ± 1:0 is consistent with SN Ia data, the nearby population of WDs and roughly consistent with other constraints from the literature. -
194 9 Ce Le B Rating 65 Ye Ars O F Br Inging As Tr on Omy T O No Rth Te X
1949 Celebrating 65 Years of Bringing Astronomy to North Texas 2014 Contact information: Inside this issue: Info Officer (General Info) – [email protected]@fortworthastro.com Website Administrator – [email protected] Postal Address: Page Fort Worth Astronomical Society May Club Calendar 4 3812 Fenton Avenue Fort Worth, TX 76133 Celestial Events 5 Web Site: http://www.fortworthastro.org Facebook: http://tinyurl.com/3eutb22 Moon Phase Calendar 6 Twitter: http://twitter.com/ftwastro Yahoo! eGroup (members only): http://tinyurl.com/7qu5vkn Mars/Venus Data Sheet 7 Officers (2013-2014): Jupiter Data Sheet 8 President – Jim Murray, [email protected] Vice President – Matt Reed, [email protected] Cloudy Night Library 9 Sec/Tres – Lewis Westerfield, [email protected] Young Astronomer News 10 Board Members: 2012-2014 Member Observing Report 11 Phil Stage Bruce Cowles Constellation Families 12 2013-2015 13 Bill Nichols AL Observing Club of the Jim Craft Constellation of the Month 14 Cover Photo Constellation Mythology 15 Composite photo courtesy FWAS Prior Club Meeting Minutes 17 members, Chris Mlodnicki and Jim Murray General Club Information 20 That’s A Fact 20 Observing Site Reminders: Be careful with fire, mind all local burn bans! November’s Full Moon 20 Dark Site Usage Requirements (ALL MEMBERS): Maintain Dark-Sky Etiquette (http://tinyurl.com/75hjajy) FWAS Foto Files 21 Turn out your headlights at the gate! Sign the logbook (in camo-painted storage shed. Inside the door on the left- hand side) E di t or : Log club equipment problems (please contact a FWAS board member to in- form them of any problems) Shawn Kirchdorfer Put equipment back neatly when finished Last person out: M ont hl y FWContributors: Check all doors – secured, but NOT locked Matt McCullar Make sure nothing is left out Russ Boatright Brian Wortham The Fort Worth Astronomical Society (FWAS) was founded in 1949 and is a non-profit scientific educational organization incorporated in the state of Texas. -
HST-ACS Photometry of the Isolated Dwarf Galaxy VV124=UGC 4879
A&A 533, A37 (2011) Astronomy DOI: 10.1051/0004-6361/201117275 & c ESO 2011 Astrophysics HST-ACS photometry of the isolated dwarf galaxy VV124=UGC 4879 Detection of the blue horizontal branch and identification of two young star clusters, M. Bellazzini1,S.Perina1, S. Galleti1, and T. Oosterloo2 1 INAF - Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna, Italy e-mail: [email protected] 2 Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo, The Netherlands Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen, The Netherlands Received 17 May 2011 / Accepted 9 July 2011 ABSTRACT We present deep V and I photometry of the isolated dwarf galaxy VV124=UGC 4879, obtained from archival images taken with the Hubble Space Telescope – Advanced Camera for Surveys. In the color-magnitude diagrams of stars at distances greater than 40 from the center of the galaxy, we clearly identify a well-populated, old horizontal branch (HB) for the first time. We show that the distribution of these stars is more extended than that of red clump stars. This implies that very old and metal-poor populations 4 dominate in the outskirts of VV124. We also identify a massive (M = 1.2 ± 0.2 × 10 M) young (age = 250 ± 50 Myr) star cluster 3 (C1), as well as another of younger age (C2, ∼<30 ± 10 Myr) with a mass similar to classical open clusters (M ≤ 3.3 ± 0.5 × 10 M). Both clusters lie at projected distances less than 100 pc from the center of the galaxy. -
Observing List
day month year Epoch 2000 local clock time: 2.00 Observing List for 24 7 2019 RA DEC alt az Constellation object mag A mag B Separation description hr min deg min 39 64 Andromeda Gamma Andromedae (*266) 2.3 5.5 9.8 yellow & blue green double star 2 3.9 42 19 51 85 Andromeda Pi Andromedae 4.4 8.6 35.9 bright white & faint blue 0 36.9 33 43 51 66 Andromeda STF 79 (Struve) 6 7 7.8 bluish pair 1 0.1 44 42 36 67 Andromeda 59 Andromedae 6.5 7 16.6 neat pair, both greenish blue 2 10.9 39 2 67 77 Andromeda NGC 7662 (The Blue Snowball) planetary nebula, fairly bright & slightly elongated 23 25.9 42 32.1 53 73 Andromeda M31 (Andromeda Galaxy) large sprial arm galaxy like the Milky Way 0 42.7 41 16 53 74 Andromeda M32 satellite galaxy of Andromeda Galaxy 0 42.7 40 52 53 72 Andromeda M110 (NGC205) satellite galaxy of Andromeda Galaxy 0 40.4 41 41 38 70 Andromeda NGC752 large open cluster of 60 stars 1 57.8 37 41 36 62 Andromeda NGC891 edge on galaxy, needle-like in appearance 2 22.6 42 21 67 81 Andromeda NGC7640 elongated galaxy with mottled halo 23 22.1 40 51 66 60 Andromeda NGC7686 open cluster of 20 stars 23 30.2 49 8 46 155 Aquarius 55 Aquarii, Zeta 4.3 4.5 2.1 close, elegant pair of yellow stars 22 28.8 0 -1 29 147 Aquarius 94 Aquarii 5.3 7.3 12.7 pale rose & emerald 23 19.1 -13 28 21 143 Aquarius 107 Aquarii 5.7 6.7 6.6 yellow-white & bluish-white 23 46 -18 41 36 188 Aquarius M72 globular cluster 20 53.5 -12 32 36 187 Aquarius M73 Y-shaped asterism of 4 stars 20 59 -12 38 33 145 Aquarius NGC7606 Galaxy 23 19.1 -8 29 37 185 Aquarius NGC7009