X-Array Aperture Configuration in Planar Or Non-Planar Spacecraft
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Darwin in the Press: What the Spanish Dailies Said About the 200Th Anniversary of Charles Darwin’S Birth
CONTRIBUTIONS to SCIENCE, 5 (2): 193–198 (2009) Institut d’Estudis Catalans, Barcelona Celebration of the Darwin Year 2009 DOI: 10.2436/20.7010.01.75 ISSN: 1575-6343 www.cat-science.cat Darwin in the press: What the Spanish dailies said about the 200th anniversary of Charles Darwin’s birth Esther Díez, Anna Mateu, Martí Domínguez Mètode, University of Valencia, Valencia, Spain Resum. El bicentenari del naixement de Charles Darwin, cele- Summary. The bicentenary of Charles Darwin’s birth, cele- brat durant el passat any 2009, va provocar un considerable brated in 2009, caused a surge in the interest shown by the augment de l’interés informatiu de la figura del naturalista an- press in the life and work of the renowned English naturalist. glès. En aquest article s’analitza la cobertura informativa This article analyzes the press coverage devoted to the Darwin d’aquest aniversari en onze diaris generalistes espanyols, i Year in eleven Spanish daily papers during the week of Dar- s’estableix grosso modo quines són les principals postures de win’s birthday and provides a brief synopsis of the positions la premsa espanyola davant de la teoria de l’evolució. D’aques- adopted by the Spanish press regarding the theory of evolu- ta anàlisi, queda ben palès com el creacionisme és encara molt tion. The analysis makes very clear the relatively strong support viu en els mitjans espanyols més conservadors. for creationism by the conservative press in Spain. Paraules clau: Charles Darwin ∙ ciència vs. creacionisme ∙ Keywords: Charles Darwin ∙ science vs. creationism ∙ tractament informatiu científic scientific news coverage “The more we know of the fixed laws of nature the more In this article, we examine to what extent and in what form incredible do miracles become.” this controversy persists in Spanish society, focusing on the print media’s response to the celebration, in 2009, of the 200th Charles Darwin (1887). -
The XMM-Newton SAS - Distributed Development and Maintenance of a Large Science Analysis System: a Critical Analysis
Astronomical Data Analysis Software and Systems XIII ASP Conference Series, Vol. 314, 2004 F. Ochsenbein, M. Allen, and D. Egret, eds. The XMM-Newton SAS - Distributed Development and Maintenance of a Large Science Analysis System: A Critical Analysis Carlos Gabriel1, John Hoar1, Aitor Ibarra1, Uwe Lammers2, Eduardo Ojero1, Richard Saxton1, Giuseppe Vacanti2 XMM-Newton Science Operations Centre, Science Operations and Data Systems Division of ESA, European Space Agency Mike Denby, Duncan Fyfe, Julian Osborne Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH, UK Abstract. The XMM-Newton Scientific Analysis System (SAS) is the software used for the reduction and calibration of data taken with the XMM-Newton satellite instruments leading to almost 400 refereed scien- tific papers published in the last 2.5 years. Its maintenance, further devel- opment and distribution is under the responsibility of the XMM-Newton Science Operations Centre together with the Survey Science Centre, rep- resenting a collaborative effort of more than 30 scientific institutes. Developed in C++, Fortran 90/95 and Perl, the SAS makes large use of open software packages such as ds9 for image display (SAO-R&D Software Suite), Grace, LHEASOFT and cfitsio (HEASARC project), pgplot, fftw and the non-commercial version of Qt (TrollTech). The combination of supporting several versions of SAS for multiple platforms (including SunOS, DEC, many Linux flavours and MacOS) in a widely distributed development process which makes use of a suite of ex- ternal packages and libraries presents substantial issues for the integrity of the SAS maintenance and development. A further challenge comes from the necessity of maintaining the flexibility of a software package evolving together with progress made in instrument calibration and anal- ysis refinement, whilst at the same time being the source of all official products of the XMM-Newton mission. -
Prime Focus (06-16).Pub
Highlights of the June Sky - - - - - - Saturn at opposition. - - - - - - DAWN: A very thin waning A Publication of the Kalamazoo Astronomical Society crescent Moon is about 2° below Mercury. Look low in east about 20 minutes before sunrise. - - - 4th - - - New Moon 11:00 pm EDT KAS - - - 9th - - - PM: Regulus, the brightest star in Leo, is about 7° to General Meeting: Friday, June 3 @ 7:00 pm the Moon’s upper left. Kalamazoo Area Math & Science Center - See Page 8 for Details - - - 10th - - - PM: The Moon is located about halfway between Observing Session: Saturday, June 11 @ 9:30 pm Regulus and Jupiter. The Moon, Mars, Jupiter & Saturn - Kalamazoo Nature Center - - - 11th - - - PM: The Moon forms a Board Meeting: Sunday, June 12 @ 5:00 pm triangle with Jupiter and Sunnyside Church - 2800 Gull Road - All Members Welcome Sigma () Leonis. - - - 12th - - - Observing Session: Saturday, June 25 @ 9:30 pm First Quarter Moon 4:10 am EDT Grand Globular Clusters - Kalamazoo Nature Center - - - 14th - - - PM: Spica, the brightest star in Virgo, is <5° below a waxing gibbous Moon. - - - 17th → 18th - - - Inside the Newsletter. PM: The Moon, Saturn, and Mars make a wide, flat May Meeting Minutes............................. p. 2 triangle, with the longest side stretching ~18° to Board Meeting Minutes......................... p. 3 connect the two planets. - - - 18th → 19th - - - Learn More About the A.L...................p. 3 PM: The Moon and Saturn are 3° to 4° apart. Observations of the Red Planet.......... p. 4 - - - 20th - - - NASA Space Place.................................. p. 5 Full Moon 7:02 am EDT June Night Sky......................................... p. 6 Summer solstice occurs at KAS Board & Announcements........... -
SUCCESSES of the HUBBLE SPACE TELESCOPE, 18Th February 2005 Astronomical History the Hubble Telescope Has Been a Major Tool for the Last Fifteen Years
SUCCESSES OF THE HUBBLE SPACE TELESCOPE, 18th February 2005 Astronomical History The Hubble telescope has been a major tool for the last fifteen years. However, astronomy is as old as man – the earliest known good star map was by Hipparchus 2500 years ago, and a Roman statue (now in Naples) is of Atlas supporting a celestial globe. In 1610 Galileo made the first telescope, opening up the sky; he was able to see the moons of Jupiter, which clearly orbited Jupiter – not Earth, then considered the absolute centre of the universe… Larger telescopes were soon built, with long tubes to accommodate the low curvature lenses that gave the best results – they were not easily manoeuvred. There is a large 28” Refractor at the Observatory in Greenwich, designated ROG, made in 1893 but on an 1859 mount, which even in London’s atmosphere is useful for planetary observation. In 19thC astronomers began to study not just the location of celestial objects but what types they were. Reflecting Telescopes These use a mirror as the prime element to gather and focus light. Small ones were made in the late 18thC, then in the early 19thC Herschel designed one with an 18” mirror. Mirrors being supported from behind, are easier to mount than lenses can only be held at the edge; they can gather more light and give a brighter, sharper image. In 1948 the 200” (5 m) Hale telescope at Mount Palomar set a new standard, high up above much of the atmosphere for maximum clarity. This was built for traditional observation by eye; then longer exposures were made possible with photographic plates; now CCDs (Charge Coupled Detectors) give higher sensitivity. -
The Space Infrared Interferometric Telescope (SPIRIT): High- Resolution Imaging and Spectroscopy in the Far-Infrared
Leisawitz, D. et al., J. Adv. Space Res., in press (2007), doi:10.1016/j.asr.2007.05.081 The Space Infrared Interferometric Telescope (SPIRIT): High- resolution imaging and spectroscopy in the far-infrared David Leisawitza, Charles Bakera, Amy Bargerb, Dominic Benforda, Andrew Blainc, Rob Boylea, Richard Brodericka, Jason Budinoffa, John Carpenterc, Richard Caverlya, Phil Chena, Steve Cooleya, Christine Cottinghamd, Julie Crookea, Dave DiPietroa, Mike DiPirroa, Michael Femianoa, Art Ferrera, Jacqueline Fischere, Jonathan P. Gardnera, Lou Hallocka, Kenny Harrisa, Kate Hartmana, Martin Harwitf, Lynne Hillenbrandc, Tupper Hydea, Drew Jonesa, Jim Kellogga, Alan Koguta, Marc Kuchnera, Bill Lawsona, Javier Lechaa, Maria Lechaa, Amy Mainzerg, Jim Manniona, Anthony Martinoa, Paul Masona, John Mathera, Gibran McDonalda, Rick Millsa, Lee Mundyh, Stan Ollendorfa, Joe Pellicciottia, Dave Quinna, Kirk Rheea, Stephen Rineharta, Tim Sauerwinea, Robert Silverberga, Terry Smitha, Gordon Staceyf, H. Philip Stahli, Johannes Staguhn j, Steve Tompkinsa, June Tveekrema, Sheila Walla, and Mark Wilsona a NASA’s Goddard Space Flight Center, Greenbelt, MD b Department of Astronomy, University of Wisconsin, Madison, Wisconsin, USA c California Institute of Technology, Pasadena, CA, USA d Lockheed Martin Technical Operations, Bethesda, Maryland, USA e Naval Research Laboratory, Washington, DC, USA f Department of Astronomy, Cornell University, Ithaca, USA g Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA h Astronomy Department, University of Maryland, College Park, Maryland, USA i NASA’s Marshall Space Flight Center, Huntsville, Alabama, USA j SSAI, Lanham, Maryland, USA ABSTRACT We report results of a recently-completed pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 µm. -
Adaptive Nulling for the Terrestrial Planet Finder Interferometer Robert D
Adaptive nulling for the Terrestrial Planet Finder Interferometer Robert D. Peters*, Oliver P. Lay, Akiko Hirai, Muthu Jeganathan Jet Propulsion Laboratory, California Institute of Technology 4800 Oak Grove Drive, Pasadena CA 91109 ABSTRACT Deep, stable starlight nulls are needed for the direct detection of Earth-like planets and require careful control of the intensity and phases of the beams that are being combined. We are testing a novel compensator based on a deformable mirror to correct the intensity and phase at each wavelength and polarization across the nulling bandwidth. We have successfully demonstrated intensity and phase control using a deformable mirror across a 100nm wide band in the near- IR, and are in the process of conducting experiments in the mid-IR wavelengths. This paper covers the current results and in the mid-IR. Keywords: Nulling interferometry, planet detection, deformable mirror, dispersion compensator, nulling, amplitude and phase correction, adaptive nuller 1. INTRODUCTION Direct detection of Earth like planets around nearby stars requires a combination of starlight suppression and high angular resolution (< 0.1 arcsec). The technique of nulling interferometry1 has been proposed at mid-infrared wavelengths for both the European Darwin mission2 and NASA’s Terrestrial Planet Finder - Interferometer (TPF-I)3. The latter is also developing a visible coronagraph architecture (TPF-C). For the case of the mid-IR interferometer, the light from the star must be suppressed by a factor of 105 or more over the bandwidth of interest, currently 7 - 17 μm. All designs under consideration include a single-mode spatial filter (SMSF) through which the combined light is passed before being detected. -
Science Enabled by High Precision Inertial Formation Flying
Science enabled by high precision inertial formation flying G. K. Skinner1∗, B. R. Dennis2, J. F. Krizmanic2;3, E. P. Kontar4 1 MPE, 85748 Garching, Germany Phone: +49 89 30000 3828 E-mail: [email protected] 2 NASA-GSFC, Greenbelt, MD 20770, USA Phone: +1 301 286 7983/6817 E-mail: Brian.R.Dennis/[email protected] 3 Universities Space Research Association (USRA), Columbia, MD 21044, USA 4 Glasgow University, G12 8QQ, UK Phone: +44 141 330 2499 E-mail: [email protected] ∗Corresponding author Abstract: The capability of maintaining two satellites in precise relative position, stable in a celestial coordinate system, would enable major advances in a number of scientific disciplines and with a variety of types of instrumentation. The common requirement is for formation flying of two spacecraft with the direction of their vector separation in inertial coordinates precisely controlled and accurately determined as a function of time. We consider here the scientific goals that could be achieved with such technology and review some of the proposals that have been made for specific missions. Types of instrumentation that will benefit from the development of this type of formation flying include 1) imaging systems, in which an optical element on one spacecraft forms a distant image recorded by a detector array on the other spacecraft, including telescopes capable of very high angular resolution; 2) systems in which the front spacecraft of a pair carries an occulting disk, allowing very high dynamic range observations of the solar corona and exoplanets; 3) interferometers, another class of instrument that aims at very high angular resolution and which, though usually requiring more than two spacecraft, demands very much the same developments. -
The Astronomy of Sir John Herschel
Introduction m m m m m m m m m m m Herschel’s Stars The Stars flourish, and in spite of all my attempts to thin them and . stuff them in my pockets, continue to afford a rich harvest. John Herschel to James Calder Stewart, July 17, 1834 n 2017, TRAPPIST-1, a red dwarf star forty light years from Earth, made headlines as the center of a system with not one or two but Iseven potentially habitable exoplanets.1 This dim, nearby star offers only the most recent example of verification of the sort of planetary system common in science fiction: multiple temperate, terrestrial worlds within a single star’s family of planets. Indeed, this discovery followed the an- nouncement only a few years earlier of the very first Earth-sized world orbiting within the habitable zone of its star, Kepler-186, five hundred light years from Earth.2 Along with other ongoing surveys and advanced instruments, the Kepler mission, which recently added an additional 715 worlds to a total of over five thousand exoplanet candidates, is re- vealing a universe in which exoplanets proliferate, Earth-like worlds are common, and planets within the habitable zone of their host star are far from rare.3 Exoplanetary astronomy has developed to the point that as- tronomers can not only detect these objects but also describe the phys- ical characteristics of many with a high degree of confidence and pre- cision, gaining information on their composition, atmospheric makeup, temperature, and even weather patterns. 3 © 2018 University of Pittsburgh Press. All rights reserved. -
Advanced Technologies for Future Space Telescopes and Instruments
Advanced Technologies for Future Space Telescopes and Instruments - A sample of upcoming astronomy missions - Interferometry in space (Darwin) - Very large telescopes in orbit (XEUS) - Future space telescope concepts (TPF) Dr. Ph. Gondoin (ESA) IR and visible astronomy missions (ESA Cosmic Vision – NASA Origin programs) DARWIN TPF GAIA SIM Herschel SIRTF Planck Eddington Kepler JWST Corot 1 GAIA Science Objective: Understanding the structure and evolution of the Galaxy PayloadGAIA payload • 2 astrometric telescopes: • Separated by 106o • SiC mirrors (1.4 m × 0.5 m) • Large focal plane (TDI operating CCDs) • 1 additional telescope equipped with: • Medium-band photometer • Radial-velocity spectrometer 2 Technology requirements for GAIA (applicable to many future space missions) • Large focal plane assemblies: – 250 CCDs per astrometry field, 3 side buttable, small pixel (9 µm), high perf. CCDs ( large CTE, low-noise, wide size, high QE), TDI operation • Ultra-stable telescope structure and optical bench: • Light weight mirror elements: – SiC mirrors (highly aspherized for good off-axis performance) Large SiC mirror for space telescopes (Boostec) ESA Herschell telescope: 1.35 m prototype 3.5 m brazed flight model (12 petals) 3 James Webb Space Telescope (JWST) Mirror Actuators Beryllium Mirrors Mirror System AMSD SBMD Wavefront Sensing and Control, Mirror Phasing Secondary mirror uses six actuators In a hexapod configuration Primary mirror segments attached to backplane using actuators in a three-point kinematic mount NIRSpec: a Multi-object -
Measuring Extended Structure in Stars Using the Keck Interferometer Nuller
Measuring Extended Structure in Stars using the Keck Interferometer Nuller Chris Koreskoa M. Mark Colavitab Eugene Serabynb Andrew Boothb and Jean Garciab aMichelson Science Center, IPAC, Caltech, Pasadena, CA 91125, USA; bJet Propulsion Laboratory, Caltech, Pasadena, CA 91109, USA ABSTRACT The Keck Interferometer Nuller is designed to detect faint off-axis mid-infrared light a few tens to a few hundreds of milliarcseconds from a bright central star. The starlight is suppressed by destructive combination along the long (85 m) baseline, which produces a fringe spacing of 25 mas at a wavelength of 10 µm, with the central null crossing the position of the star. The strong, variable mid-infrared background is subtracted using interferometric phase chopping along the short (5 m) baseline. This paper presents an overview of the observing and data reduction strategies used to produce a calibrated measurement of the off-axis light. During the observations, the instrument cycles rapidly through several calibration and measurement steps, in order to monitor and stabilize the phases of the fringes produced by the various baselines, and to derive the fringe intensity at the constructive peak and destructive null along the long baseline. The data analysis involves removing biases and coherently demodulating the short-baseline fringe with the long-baseline fringe tuned to alternate between constructive and destructive phases, combining the results of many measurements to improve the sensitivity, and estimating the part of the null leakage signal which is associated with the finite angular size of the central star. Comparison of the results of null measurements on science target and calibrator stars permits the instrumental leakage - the “system null leakage” - to be removed and the off-axis light to be measured. -
System Design and Technology Development for the Terrestrial
System design and technology development for the Terrestrial Planet Finder infrared interferometer Gary Blackwood*, Eugene Serabyn, Serge Dubovitsky, MiMi Aung, Steven M. Gunter, Curt Henry Jet Propulsion Laboratory ABSTRACT This paper describes the technical program that will demonstrate the viability of two mid-infrared interferometer architectures being developed for the Terrestrial Planet Finder (TPF) to support a mission concept downselect in 2006. The TPF science objectives are to survey a statistically significant number of nearby solar-type stars for radiation from terrestrial planets, to characterize these planets and to then perform spectroscopy for detection of biomarkers. A 4- telescope, 36-m Structurally-Connected Interferometer using a dual-chopped Bracewell nuller will meet the minimum science requirement to completely survey 30 nearby stars and partially survey 120 others. A Formation-Flying Interferometer will meet the full science requirement to completely survey 150 stars, and involves a trade between dual- chopped Bracewell, degenerate Angel Cross, and the Darwin bow-tie input pupil. The system engineering trades for the connected structure and formation-flying architectures are described. The top technical concems for these architectures are mapped to technology developments that will retire these concems prior to the project downselect between a mid- infrared nulling interferometer and a visible coronagraph. Keywords: interferometry, terrestrial planets, nulling, formation-flying, cryogenic structures 1. INTRODUCTION The goals of the Terrestrial Planet Finder (TPF) are to detect and characterize terrestrial-sized planets around nearby stars for signs of habitability and for evidence of life. The TPF science requirements are to survey a statistically meaningful number of solar-type stars for radiation from terrestrial planets, to characterize these planets and their orbital parameters, and to then perform follow-up spectroscopy on promising targets. -
Research and Scientific Support Department 2003 – 2004
COVER 7/11/05 4:55 PM Page 1 SP-1288 SP-1288 Research and Scientific Research Report on the activities of the Support Department Research and Scientific Support Department 2003 – 2004 Contact: ESA Publications Division c/o ESTEC, PO Box 299, 2200 AG Noordwijk, The Netherlands Tel. (31) 71 565 3400 - Fax (31) 71 565 5433 Sec1.qxd 7/11/05 5:09 PM Page 1 SP-1288 June 2005 Report on the activities of the Research and Scientific Support Department 2003 – 2004 Scientific Editor A. Gimenez Sec1.qxd 7/11/05 5:09 PM Page 2 2 ESA SP-1288 Report on the Activities of the Research and Scientific Support Department from 2003 to 2004 ISBN 92-9092-963-4 ISSN 0379-6566 Scientific Editor A. Gimenez Editor A. Wilson Published and distributed by ESA Publications Division Copyright © 2005 European Space Agency Price €30 Sec1.qxd 7/11/05 5:09 PM Page 3 3 CONTENTS 1. Introduction 5 4. Other Activities 95 1.1 Report Overview 5 4.1 Symposia and Workshops organised 95 by RSSD 1.2 The Role, Structure and Staffing of RSSD 5 and SCI-A 4.2 ESA Technology Programmes 101 1.3 Department Outlook 8 4.3 Coordination and Other Supporting 102 Activities 2. Research Activities 11 Annex 1: Manpower Deployment 107 2.1 Introduction 13 2.2 High-Energy Astrophysics 14 Annex 2: Publications 113 (separated into refereed and 2.3 Optical/UV Astrophysics 19 non-refereed literature) 2.4 Infrared/Sub-millimetre Astrophysics 22 2.5 Solar Physics 26 Annex 3: Seminars and Colloquia 149 2.6 Heliospheric Physics/Space Plasma Studies 31 2.7 Comparative Planetology and Astrobiology 35 Annex 4: Acronyms 153 2.8 Minor Bodies 39 2.9 Fundamental Physics 43 2.10 Research Activities in SCI-A 45 3.