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The Comet's Tale
THE COMET’S TALE Newsletter of the Comet Section of the British Astronomical Association Volume 9, No 1 (Issue 17), 2002 April JOEL HASTINGS METCALF MINISTER, HUMANITARIAN, ASTRONOMER Richard R Didick Joel Hastings Metcalf was born in The following account, taken used with either a single prism or Meadville, Pennsylvania, on from a newspaper article about a grating, both of which were January 4th, 1866, the son of him when he lived in Taunton, is provided. Lewis Herbert and Anna (Hicks) somewhat dubious since he Metcalf. Lewis was a Civil War actually bought the 7-inch In the observatory at Keesville, Veteran, a soldier who lost a leg refractor. "When but 14 years old the instrument was mounted in a at the first battle of "Bull Run" he built a telescope and ground very substantial dome, being and was held at Libby prison until out a lens with which he was able fastened to a fine cut granite base exchanged and discharged. to observe with success all the weighting about a ton. In a principal heavenly bodies. This February when Lake Champlain At the approximate age of 14, Joel was a small two-inch lens. His had frozen over, the whole outfit Metcalf borrowed Richard next attempt was a three-inch lens was loaded on sleds and started Proctor's book, Other Worlds and he later made one of three across the Lake on the ice. The Than Ours, from his Sunday and a half inches, which he ice was thick enough - but there school library which led him to an subsequently sold to Harvard are always long cracks in the interest in astronomy. -
19740026181.Pdf
DYNAMIC& AND PHOTOMETRIC INVESTIGATION OF COMETARY TYPE I1 TAILS Grant NGR 09-015-159 Semiannual Progress Report No. 6 For the period March 15 to September 14, 1974 Principal Investigator Dr. Zdenek Sekanina Prepared for . .-- National Aeronautics and Space Administration ; . Washington, D.C. 20546 q, ' ';'.. ',. : , , , - , .., ,: .,M, ._I _, . ..!..' , , .. ".. .,;-'/- Smithsonian Institution Astrophysical Observatory Cambridge, Massachusetts 02138 DYNAMICAL AND PHOTOMETRIC INVESTIGATION OF COMETARY TYPE 11 TAILS Grant NGR 09-015-159 Semiannual Progress Report No. 6 For the period March 15 to September 14, 1974 Principal Investigator Dr. Zdenek Sekanina Pre-ared for National Aeronautics and Space Administration Washington, D. C. 20546 Smithsonian Institut ion Astrophysical Observatory Sambridge, Massachusetts 02138 TABLE OF CONTENTS ABSTRACT ........................... iii PART A. COMPARISON OF THE WORKING MODEL FOR THE ANTITAIL OF COMET KOHOUTEK (1973f) WITH GROUND-BASED PHOTOGRAPHIC OBSERVATIONS . 1 1. Introduction ....................... 1 11. The Cerro Tololo photographs ............... 1 111. Photographic photometry of the Cerro Tololo plates. The technique ........................ 4 IV. Photographic photometry of the Cerro Tololo plates. The results ......................... V. Calibration stars for the Cerro Tololo plates ....... VI. Preliminary physical interpretation of the observed radial profiles of the antitail ................. VII. References ....................... PART B. OTHER ACTIVITIES IN THE REPORTED PERIOD ........... -
Cronología De Lanzamientos Espaciales
Cronología de lanzamientos espaciales Cronología de Lanzamientos Espaciales Año 2011 Copyright © 2009 by Eladio Miranda Batlle. All rights reserved. Los textos, imágenes y tablas que se encuentran en esta cronología cuentan con la autorización de sus propietarios para ser publicadas o se hace referencia a la fuente de donde se obtuvieron los mismos. Eladio Miranda Batlle [email protected] Cronología de lanzamientos espaciales Contenido 2011 Enero 20.05.2011 Telstar 14R (Estrela do Sul 2) 20.01.11 KH-12 USA224 20.05.2011 ST 2 / GSat 8 (Insat 4G) 20.01.11 Elektro-L 22.01.11 HTV 2 /Kounotori-2. Junio 28.01.11 Progress-M 09M/ARISSat 07.06.2011 Soyuz TMA-02M/27S Febrero 10.06.2011 Aquarius (SAC D, ESSP 6) 15.06.2011 Rasad 1 01.02.11 Cosmos 2470 Geo-lk-2 20.06.2011 ZX 10 (ChinaSat 10) 06.02.11 RPP (USA 225,NROL 66) 21.06.2011 Progress-M 11M 16.02.11 ATV 2 (Johannes Kepler) 27.06.2011 Kosmos 2472 (Yantar- 24.02.11 Discovery F39(STS133) 4K2M #7) /PMM(Leonardo)/ELC 4 30.06.2011 ORS 1 26.02.11 Kosmos 2471(Urangan-K1) Julio Marzo 06.07.2011 SJ 11-03 04.03.11 Glory/ E1P/ KySat 1/ 08.07.2011 Atlantis F33 (STS-135) Hermes MPLM 2-04 (Raffaello 05.03.11 X-37B OTV-2 (USA 226) F4) PSSC-Testbed 2 11.03.11 SDS-3 6(USA 227, NROL 11.07.2011 TL 1B (Tianlian) 27) 13.07.2011 Globalstar MO81/83/85/88/89/91 15.07.2011 GSat 12 Abril 15.07.2011 SES 3 / Kazsat 2 16.07.2011 GPS-2F 2 (Navstar 66, 04.04.11 Soyuz TMA 21 USA 231) 09.04.11 BD-2 13 18.07.2011 Spektr-R (Radio-Astron) 15.04.11 NOSS-35A (USA 229, 26.07.2011 BD-2 I4 NROL 34) 29.07.2011 SJ 11-02 20.04.11 -
Tim Peake Tells All Slim Satellite for Star Wars
Spaceflight A British Interplanetary Society Publication Tim Peake tells all Slim satellite for Star Wars Fantastic Philae! SAMPLE Apollo 15’s room with a view Vol 57 No 1 January 2015 £4.50 www.bis-space.com 1.indd 441 11/27/2014 9:48:17 AM CONTENTS Editor: Published by the British Interplanetary Society David Baker, PhD, BSc, FBIS Volume 57 No. 1 January 2015 Sub-editor: Ann Page 18 Antares Falters Production Assistant: As the forensic engineering analysis of the failure of an Antares Ben Jones rocket on 28 October reaches its preliminary conclusions, what was Spaceflight Promotion: responsible for the catastrophic loss of more than 2 tonnes of cargo Suszann Parry for the ISS and what impact will it have on the future for Orbital SPACEFLIGHT OFFICE Sciences? 27/29 South Lambeth Road, London, SW8 1SZ, England. 19-22 The Apollo 15 Standup EVA Tel: +44 (0)20 7735 3160 Space historian Joel W Powell digs out the details on Apollo 15 Fax: +44 (0)20 7587 5118 commander Dave Scott’s unique survey of the Hadley Apennine Email: [email protected] landing site from his position standing on the ascent engine cover, www.bis-space.com head and shoulders out the top of the Lunar Module Falcon. ADVERTISING 23-25 Tim Peake Speaks of Principia Tel: +44 (0)1424 883401 Spaceflight’s Nick Spall talks to British astronaut Tim Peake about Email: [email protected] his Principia mission, now less than a year away from launch on a DISTRIBUTION Soyuz spacecraft to the ISS where he will remain for approximately six Spaceflight may be received worldwide by months. -
The Cometary Antitail
return to updates The Cometary Antitail by Miles Mathis First published March 5, 2013 Comet Tail. Comet ISON is already generating excitement, since it is predicted to be one of the brightest ever seen in our lifetimes. It is scheduled to pass beginning November 28. The comet PANSTARRS is currently being seen in the south and will soon be seen here as well. This gives me the opportunity to address cometary theory, how it currently fails, and how to improve it with the unified field. Let's look at the antitail. The antitail is one of three cometary tails known, along with the dust tail and the ion tail. The ion tail points directly away from the Sun, and is caused by the Solar wind. According to this diagram above, the dust tail appears to point mainly on the tangent, behind the comet, and so it forms a pretty natural exhaust tail. But the antitail is not so easy to explain with current theory. It is a dust tail that leads the comet, so it is neither exhaust nor ion push caused by the Sun. This is what Wikipedia says on the main page for “comet”: On occasions a short tail pointing in the opposite direction to the ion and dust tails may be seen – the antitail. These were once thought somewhat mysterious, but are merely the end of the dust tail apparently projecting ahead of the comet due to our viewing angle. But if we click on the “antitail” link on that page, we don't find that explanation. -
Commercial Space Transportation: 2011 Year in Review
Commercial Space Transportation: 2011 Year in Review COMMERCIAL SPACE TRANSPORTATION: 2011 YEAR IN REVIEW January 2012 HQ-121525.INDD 2011 Year in Review About the Office of Commercial Space Transportation The Federal Aviation Administration’s Office of Commercial Space Transportation (FAA/AST) licenses and regulates U.S. commercial space launch and reentry activity, as well as the operation of non-federal launch and reentry sites, as authorized by Executive Order 12465 and Title 51 United States Code, Subtitle V, Chapter 509 (formerly the Commercial Space Launch Act). FAA/AST’s mission is to ensure public health and safety and the safety of property while protecting the national security and foreign policy interests of the United States during commercial launch and reentry operations. In addition, FAA/ AST is directed to encourage, facilitate, and promote commercial space launches and reentries. Additional information concerning commercial space transportation can be found on FAA/AST’s web site at http://www.faa.gov/about/office_org/headquarters_offices/ast/. Cover: Art by John Sloan (2012) NOTICE Use of trade names or names of manufacturers in this document does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the Federal Aviation Administration. • i • Federal Aviation Administration / Commercial Space Transportation CONTENTS Introduction . .1 Executive Summary . .2 2011 Launch Activity . .3 WORLDWIDE ORBITAL LAUNCH ACTIVITY . 3 Worldwide Launch Revenues . 5 Worldwide Orbital Payload Summary . 5 Commercial Launch Payload Summaries . 6 Non-Commercial Launch Payload Summaries . 7 U .S . AND FAA-LICENSED ORBITAL LAUNCH ACTIVITY . 9 FAA-Licensed Orbital Launch Summary . 9 U .S . and FAA-Licensed Orbital Launch Activity in Detail . -
Changes to the Database for May 1, 2021 Release This Version of the Database Includes Launches Through April 30, 2021
Changes to the Database for May 1, 2021 Release This version of the Database includes launches through April 30, 2021. There are currently 4,084 active satellites in the database. The changes to this version of the database include: • The addition of 836 satellites • The deletion of 124 satellites • The addition of and corrections to some satellite data Satellites Deleted from Database for May 1, 2021 Release Quetzal-1 – 1998-057RK ChubuSat 1 – 2014-070C Lacrosse/Onyx 3 (USA 133) – 1997-064A TSUBAME – 2014-070E Diwata-1 – 1998-067HT GRIFEX – 2015-003D HaloSat – 1998-067NX Tianwang 1C – 2015-051B UiTMSAT-1 – 1998-067PD Fox-1A – 2015-058D Maya-1 -- 1998-067PE ChubuSat 2 – 2016-012B Tanyusha No. 3 – 1998-067PJ ChubuSat 3 – 2016-012C Tanyusha No. 4 – 1998-067PK AIST-2D – 2016-026B Catsat-2 -- 1998-067PV ÑuSat-1 – 2016-033B Delphini – 1998-067PW ÑuSat-2 – 2016-033C Catsat-1 – 1998-067PZ Dove 2p-6 – 2016-040H IOD-1 GEMS – 1998-067QK Dove 2p-10 – 2016-040P SWIATOWID – 1998-067QM Dove 2p-12 – 2016-040R NARSSCUBE-1 – 1998-067QX Beesat-4 – 2016-040W TechEdSat-10 – 1998-067RQ Dove 3p-51 – 2017-008E Radsat-U – 1998-067RF Dove 3p-79 – 2017-008AN ABS-7 – 1999-046A Dove 3p-86 – 2017-008AP Nimiq-2 – 2002-062A Dove 3p-35 – 2017-008AT DirecTV-7S – 2004-016A Dove 3p-68 – 2017-008BH Apstar-6 – 2005-012A Dove 3p-14 – 2017-008BS Sinah-1 – 2005-043D Dove 3p-20 – 2017-008C MTSAT-2 – 2006-004A Dove 3p-77 – 2017-008CF INSAT-4CR – 2007-037A Dove 3p-47 – 2017-008CN Yubileiny – 2008-025A Dove 3p-81 – 2017-008CZ AIST-2 – 2013-015D Dove 3p-87 – 2017-008DA Yaogan-18 -
Samson's Long Hair (Strength Hidden) | Coma, Stream Or Tail
Sabine Vlaming <[email protected]> Comet means 'long haired star' in Greek | Samson's long hair (strength hidden) | Coma, stream or tail | Coma Berenices: hidden behind hair | His tail drew a third of the stars | Is Revelation 8:8 Hawaii (and the stored chemicals) Sabine Vlaming <[email protected]> 15 juli 2020 om 08:47 Aan: Sabine Vlaming <[email protected]> ---------- Forwarded message --------- Van: Sabine Vlaming <[email protected]> Date: za 11 aug. 2018 om 12:52 Subject: Comet means 'long haired star' in Greek | Samson's long hair (strength hidden) | Coma, stream or tail | Coma Berenices: hidden behind hair | His tail drew a third of the stars | Is Revelation 8:8 Hawaii (and the stored chemicals) To: Comet | 'Long haired' star | Another association with samson | Nudge to Coma Berenices too From Wikipedia, the free encyclopedia JumpThis article is about the astronomical objects. For other uses, see Comet (disambiguation). to A comet is an icy small Solar System body that, when searchnavigation passing close to the Sun, warms and begins to release gases, a process called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred metres to tens of kilometres across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times the Earth's diameter, while the tail may stretch one astronomical unit. If sufficiently bright, a comet may be seen from the Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. -
Comets: Data, Problems, and Objectives
Comets: Data, Problems, and Objectives Fred L. Whipple Center for Astrophysics Cambridge, Massachusetts A highly abridged review of new relevant results from the observations of Comet Kohoutek (1973f) is followed by an outline summary of our basic knowledge concerning comets, both subjects being confined to data related to the nature and origin of comets rather than the phenomena (for example, plasma phenomena are omitted). The discussion then centers on two likely places of cometary origin in the developing solar system, the proto-Uranus-Neptune region versus the much more distant fragmented interstellar cloud region, now frequented by comets of the Opik-Oort cloud. The Comet Kohoutek results add new insights, particularly with regard to the parent molecules and the nature of meteoric solids in comets, to restrict the range of the physical circumstances of comet formation. A few fundamental and outstanding questions are asked, and a plea made for unmanned missions to comets and asteroids in order to provide definitive answers as to the nature and origin of comets, asteroids, and the solar system generally. A Few of the Major Advances in Lew and Heiber (ref. 9) and Herzberg and Lew (ref. 10) made a major step forward by Comet Knowledge From + identifying H20 bands which were measured Observations of Comet by Benevenuti and Wurm (ref. 11) and by Kohoutek (1973f) Wehinger et al. (ref. 12). Definitive studies of this vital ion should solidify our knowledge The first radio observations of a comet of the abundance and behavior of H20, ap- leading to the discovery of the new parent parently the most abundant and controlling molecules methyl cyanide (CH3CN) and material in comets. -
Forward-Scattering Enhancement of Comet Brightness
Forward-Scattering Enhancement of Comet Brightness. III. Prospects for C/2010 (Elenin) as Viewed from the Earth and the SOHO, STEREO-A, and STEREO-B Spacecraft ____________________ Joseph N. Marcus 19 Arbor Road St. Louis, MO 63132 USA [email protected] _____________ Submitted to International Comet Quarterly 2011 July 28 Abstract Comet C/2010 X1 (Elenin) ventures into extreme forward-scattering geometry when it passes between the Sun and the STEREO-B spacecraft (minimum scattering angle θmin = 7.3° on Aug. 13.13 UT), the Earth (θmin = 3.1° on Sept. 26.78 UT), and the SOHO spacecraft (θmin = 3.1° on Sept. 26.90 UT). Near these times, brightness enhancements of −6 to −7 magnitudes from the baseline can be expected, based on a model of the coma scattering function, Φ(θ) (Marcus 2007a). Large as they are, these predicted enhancements are blunted by the comet’s extremely low dust-to-gas light ratio, inferred as δ90 = 0.15 from current continuum photometry. I analyze current visual magnitudes through June and develop a model for a baseline light curve which incorporates a dust-to-gas light ratio, δ90(r), which varies with heliocentric distance, r. The model predicts a falloff in the index of brightening of C/2010 X1 from n = 4 at r > 1 AU to n = 3 at r < 1 AU in the canonical baseline total magnitude formula m1 = H0 + 5 log ∆ + 2.5 n log r + mΦ(θ), where mΦ(θ) = − 2.5 log Φ(θ), ∆ is comet-observer distance, and H0 = 8.0 is the derived absolute magnitude. -
Computational Physics Project 3 Comet Dust Tails
Computational Physics Project 3 Comet Dust Tails Outline ● Comet Dust Tails ● Forces acting on Dust Particles ● Two basic elements of calculation – Acceleration of dust grain near nucleus – Subsequent motion of dust grain in orbit ● Calculation Parameters and Questions to be considered Comet Tails ● Ion Tail – ionized gas driven away from sun by solar wind Ion Tail ● Dust Tail – Dust particles pushed by solar radiation pressure Dust – Curved shape with respect Tail to the nucleus is result of orbital motion of particles responding to the radiation pressure. Dust Tail Features ● Anti-tail – Large dust particles an move sunward before turning around under radiation pressure. – Most in plane of orbit ● Structures in Tail – Produced by changes in the amount of dust with time. ● We are going to try to explain these features. Dust Tail Forces ● Gravity of Sun – Nucleus in orbit around Sun, no other forces will be considered in calculating position of nucleus. – Dust grain in orbit around Sun, so solar gravity must be considered. ● Gravity of Comet – Dust grain feels gravity of comet. ● Drag of outflowing gas from the comet – Dust grain pushed by outflowing gas ● Solar Radiation Pressure – Dust grain pushed by radiation pressure of sunlight Gravity Force Geometry This shows where the dust Is with respect to the nucleus NUCLEUS r - r d n r DUST n GRAIN r d SUN Drag A density of air in cylinder: ρ Projectile distance travelled in ∆t = ∆L Mass of air molecules encountered in time ∆t: m = ρ A ∆L = d A v ∆t Energy imparted to air molecules through collision: ∆E ~ ½ m v2 ~ ½ ρ A v2 ∆L Energy comes from projectile: Work done = Drag Force X ∆L ∆E = Drag Force ∆L ~ ½ ρ A v2 ∆L Drag Force ~ ½ ρ A v2 Drag on Dust Grain C is drag coefficient drag v is gas velocity – gas is directed radially outward from nucleus gas A is cross section of grain ρ is gas density gas Q is number of water molecules per second MH2O is mass of water Where r is distance from comet nucleus molecule and R is radius of comet nucleus. -
Comets II, Revised Chapter #7006
Comets II, Revised Chapter #7006 Motionofcometarydust Marco Fulle INAF { Osservatorio Astronomico di Trieste Summary. On time{scales of days to months, the motion of cometary dust is mainly affected by solar radiation pressure, which determines dust dynamics according to its cross{section. Within this scenario, dust motion builds{up structures named dust tails. Tail photometry, depending on the dust cross section too, allows models to infer the best available outputs describing fundamental dust parameters: mass loss rate, ejection velocity from the coma, and size distribution. Only models taking into account all these parameters, each strictly linked to all others, can provide self{consistent estimates of each of them. All available tail models find that comets release dust with its mass dominated by the largest ejected boulders. A much more unexpected result is however possible: also coma brightness may be dominated by meter{sized boulders. This result, if confirmed by future observations, would require deep revisions of most dust coma models, based on the common assumption that coma light is coming from grains of sizes close to the observation wavelength. 1. HISTORICAL OVERVIEW While ices sublimate on the nucleus surface, the dust embedded in it is released and dragged out by the gas expanding in the coma. The dust motion then depends on the following boundary conditions: the 3D nucleus topography and the complex 3D gas{dust interaction close to the nucleus surface. Both these conditions were never available to modelers. Dust coma shapes heavily depend on the details of the boundary conditions, and coma models cannot disentangle the effect of dust parameters on coma shapes from those due to the unknown boundary conditions.