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AATSR Frequently Asked Questions (FAQ)
AATSR Frequently Asked Questions (FAQ) Author : IDEAS+ AATSR QC Team (Telespazio VEGA UK) IDEAS+-VEG-OQC-REP-2117 Issue 3 14 December 2016 AATSR Frequently Asked Questions (FAQ) Issue 3 AMENDMENT RECORD SHEET The Amendment Record Sheet below records the history and issue status of this document. ISSUE DATE REASON 1 20 Dec 2005 Initial Issue (as AEP_REP_001) 2 02 Oct 2013 Updated with new questions and information (issued as IDEAS- VEG-OQC-REP-0955) 3 14 Dec 2016 General updates, major edits to Q37., new questions: Q17., Q25., Q26., Q28., Q32., Q38., Q39., Q48. Now issued as IDEAS+-VEG-OQC-REP-2117 TABLE OF CONTENTS 1. INTRODUCTION ........................................................................................................................ 5 1.1 The Third AATSR Reprocessing Dataset (IPF 6.05) ............................................................ 5 1.2 References ............................................................................................................................ 6 2. GENERAL QUESTIONS ........................................................................................................... 7 Q1. What does AATSR stand for? ........................................................................................ 7 Q2. What is AATSR and what does it do? ............................................................................ 7 Q3. What is Envisat? ............................................................................................................. 7 Q4. What orbit does Envisat use? ........................................................................................ -
Society News Science News the Antikythera Mechanism Skinakas Observatory Spectroscopic Diagnostics of Galactic Nuclei Eclipsing Binaries
HIPPARCHOSHIPPARCHOS The Hellenic Astronomical Society Newsletter Volume 2, Issue 2 Society News Science News The Antikythera Mechanism Skinakas observatory Spectroscopic Diagnostics of Galactic Nuclei Eclipsing Binaries ISSN: 1790-9252 ʸ˱ˤ˳˶˱˹˯˩˭ˮˬ˰˱˙ ƋƜƠƦƓ6SHFLDO(GLWLRQ °ĆāąĆąõýĉýĊýĈØĉĊćąăąĂõ÷Ĉ çąÿąĈāóûÿĒĊÿý÷ĉĊćąăąĂõ÷ĆćóĆûÿă÷ûõă÷ÿĆûćõĆāąĀýØČôĉĊû Ċą 1H[6WDU 6( ă÷ ĉ÷Ĉ øąýþôĉûÿ ă÷ øćûõĊû čÿāÿòúûĈ ÷ĉĊóćûĈ Ćā÷ăôĊûĈù÷ā÷ĄõûĈĀ÷ÿòāā÷ĂûĊąĆòĊýĂ÷ûăĒĈĀąċĂĆÿąēÞ ăó÷ ąÿĀąùóăûÿ÷ 1H[6WDU 6( ĉċăúċòüûÿ ĆćďĊąČ÷ăô ûċčćýĉĊõ÷ Ăû ûĄûāÿùĂóăûĈ āûÿĊąċćùõûĈ Ā÷ÿ ÷ĆõĉĊûċĊą āĒùą ÷Ąõ÷Ĉ ĆćąĈ ĊÿĂô Ûûă Ćûćÿā÷ĂøòăûĊ÷ÿ ý Ćÿþ÷ăĒĊýĊ÷ ă÷ Ċą ĂûĊ÷ăÿĔĉûÿ ą ÷ùąć÷ĉĊôĈ ƌƞƢƜƨơƱƠƥ ăó÷ ąÿĀąùóăûÿ÷ 1H[6WDU 6( öÁ &HOHVWURQ ´¹ÅÀ«µ´¸ 1H[6WDU6( ĊýăĊûāûċĊ÷õ÷āóĄýĊýĈĊûčăąāąùõ÷ĈĒĆďĈĆāôćďĈ ÷ċĊąĂ÷ĊąĆąÿýĂóăą āûÿĊąċćùÿĀĒ ĉēĉĊýĂ÷ úċă÷ĊĒĊýĊ÷ ÷ă÷øòþĂÿĉýĈ Ăóĉď IODVK Ċąċ čûÿćÿĉĊýćõąċ ĊÿĈ ĀąćċČ÷õûĈ ãæäêÜâæ 1H[6WDU6( êëçæé 0DNVXWRY&DVVHJUDLQ¡¾»¿¾Ã¸¹Ë*R7R ûĆÿĉĊćĔĉûÿĈ 6WDU%ULJKW ;/7 Ċą ûĆ÷ă÷ĉĊ÷ĊÿĀĒ āąùÿĉĂÿĀĒ ÛàØãÜêèæéáØêæçêèæë PP l ûċþċùćòĂĂÿĉýĈĊąċĊýāûĉĀąĆõąċ6N\$OLJQpĀ÷ÿĆąāāòòāā÷ ÜéêØçæéêØéÞ PP ÜéêâæÚæé I £¢ ¢£¡¨¢¢ 6WDU%ULJKW;/7 ãûĊą1H[6WDU6(ûõĉĊûĉĊýþóĉýĊąċąúýùąēØĆāòûĆÿāóĄĊû ãÜÚïìÜâãÜÚÜßëäéÞ [ óă÷÷ăĊÿĀûõĂûăą÷ĆĒĊąĂûăąēĀ÷ÿĊąĊýāûĉĀĒĆÿąþ÷Ċąøćûÿùÿ÷ æèàØáæìØàäãÜÚÜßæé éêÞèàåÞ ØāĊ÷üÿĂąċþÿ÷Āô»´»¾Ã¬À ĉ÷ĈíćýĉÿùƹÿĔăĊ÷ĈĊýăĊûčăąāąùõ÷1H[6WDUĊ÷ĊýāûĉĀĒĆÿ÷ ¡¢¥ PP PP(/X[ 6( óčąċă Ċýă ÿĀ÷ăĒĊýĊ÷ ă÷ ûăĊąĆõĉąċă ĆûćõĆąċ ¡¤£¢ 6WDU3RLQWHU ÷ăĊÿĀûõĂûă÷ êą ĂĒăą Ćąċ óčûĊû ă÷ ĀòăûĊû ûõă÷ÿ ă÷ ĀąÿĊòĄûĊû £¡ ¢ 뺸¼¾Á ¨ PP »´kIOLSPLUURUl Ăóĉ÷÷ĆĒĊąĆćąĉąČþòāĂÿąĀ÷ÿă÷÷Ćąā÷ēĉûĊûĊąþó÷Ă÷ ÙØèæé NJ Ûûă ĄóćûĊû Ćąÿą ÷ăĊÿĀûõĂûăą ă÷ ûĆÿāóĄûĊû -
Cloud Cci ATSR-2 and AATSR Dataset Version 3: a 17-Year Climatology of Global Cloud and Radiation Properties Caroline A
Discussions https://doi.org/10.5194/essd-2019-217 Earth System Preprint. Discussion started: 11 December 2019 Science c Author(s) 2019. CC BY 4.0 License. Open Access Open Data Cloud_cci ATSR-2 and AATSR dataset version 3: a 17-year climatology of global cloud and radiation properties Caroline A. Poulsen1, Gregory R. McGarragh2, Gareth E. Thomas3,6, Martin Stengel4, Matthew W. Christensen5, Adam C. Povey7, Simon R. Proud5,6, Elisa Carboni3,6, Rainer Hollmann4, and Roy G. Grainger7 1Monash University, Melbourne, Australia 2Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK Now at Cooperative Institute for Research in the Atmosphere, Colorado State University 3Science Technology Facility Council, Rutherford Appleton Laboratory, Harwell, Oxfordshire, UK 4Deutscher Wetterdienst, Frankfurter Str. 135, 63067, Offenbach, Germany 5Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK 6National Centre for Earth Observation, Reading RG6 6BB, UK 7National Centre for Earth Observation, Atmospheric, Oceanic and Planetary Physics, University of Oxford, Parks Road, Oxford OX1 3PU, U.K. Correspondence: Caroline Poulsen ([email protected]) Abstract. We present version 3 (V3) of the Cloud_cci ATSR-2/AATSR dataset. The dataset was created for the European Space Agency (ESA) Cloud_cci (Climate Change Initiative) program. The cloud properties were retrieved from the second Along- Track Scanning Radiometer (ATSR-2) on board the second European Remote Sensing Satellite (ERS-2) spanning 1995-2003 and the Advanced ATSR (AATSR) on board Envisat, which spanned 2002-2012. The data comprises a comprehensive set 5 of cloud properties: cloud top height, temperature, pressure, spectral albedo, cloud effective emissivity, effective radius and optical thickness alongside derived liquid and ice water path. -
FAME-C: Cloud Property Retrieval Using Synergistic AATSR and MERIS Observations
Atmos. Meas. Tech., 7, 3873–3890, 2014 www.atmos-meas-tech.net/7/3873/2014/ doi:10.5194/amt-7-3873-2014 © Author(s) 2014. CC Attribution 3.0 License. FAME-C: cloud property retrieval using synergistic AATSR and MERIS observations C. K. Carbajal Henken, R. Lindstrot, R. Preusker, and J. Fischer Institute for Space Sciences, Freie Universität Berlin (FUB), Berlin, Germany Correspondence to: C. K. Carbajal Henken ([email protected]) Received: 29 April 2014 – Published in Atmos. Meas. Tech. Discuss.: 19 May 2014 Revised: 17 September 2014 – Accepted: 11 October 2014 – Published: 25 November 2014 Abstract. A newly developed daytime cloud property re- trievals. Biases are generally smallest for marine stratocu- trieval algorithm, FAME-C (Freie Universität Berlin AATSR mulus clouds: −0.28, 0.41 µm and −0.18 g m−2 for cloud MERIS Cloud), is presented. Synergistic observations from optical thickness, effective radius and cloud water path, re- the Advanced Along-Track Scanning Radiometer (AATSR) spectively. This is also true for the root-mean-square devia- and the Medium Resolution Imaging Spectrometer (MERIS), tion. Furthermore, both cloud top height products are com- both mounted on the polar-orbiting Environmental Satellite pared to cloud top heights derived from ground-based cloud (Envisat), are used for cloud screening. For cloudy pixels radars located at several Atmospheric Radiation Measure- two main steps are carried out in a sequential form. First, ment (ARM) sites. FAME-C mostly shows an underestima- a cloud optical and microphysical property retrieval is per- tion of cloud top heights when compared to radar observa- formed using an AATSR near-infrared and visible channel. -
Synthetic Aperture Radar in Europe: ERS, Envisat, and Beyond
SYNTHETIC APERTURE RADAR IN EUROPE Synthetic Aperture Radar in Europe: ERS, Envisat, and Beyond Evert Attema, Yves-Louis Desnos, and Guy Duchossois Following the successful Seasat project in 1978, the European Space Agency used advanced microwave radar techniques on the European Remote Sensing satellites ERS-1 (1991) and ERS-2 (1995) to provide global and repetitive observations, irrespective of cloud or sunlight conditions, for the scientific study of the Earth’s environment. The ERS synthetic aperture radars (SARs) demonstrated for the first time the feasibility of a highly stable SAR instrument in orbit and the significance of a long-term, reliable mission. The ERS program has created opportunities for scientific discovery, has revolutionized many Earth science disciplines, and has initiated commercial applica- tions. Another European SAR, the Advanced SAR (ASAR), is expected to be launched on Envisat in late 2000, thus ensuring the continuation of SAR data provision in C band but with important new capabilities. To maximize the use of the data, a new data policy for ERS and Envisat has been adopted. In addition, a new Earth observation program, The Living Planet, will follow Envisat, offering opportunities for SAR science and applications well into the future. (Keywords: European Remote Sensing satellite, Living Planet, Synthetic aperture radar.) INTRODUCTION In Europe, synthetic aperture radar (SAR) technol- Earth Watch component of the new Earth observation ogy for polar-orbiting satellites has been developed in program, The Living Planet, and possibly the scientific the framework of the Earth observation programs of Earth Explorer component will include future SAR the European Space Agency (ESA). -
Project's User Guide
User guide Editors: Sofoklis Sotirou, Nikolaos Dalamagkas Artwork: Sylvia Pentheroudaki, Evaggelos Anastasiou Ellinogermaniki Agogi This edition is co-financed by European Commission Copyright 2006 by Ellinogermaniki Agogi All rights reserved Reproduction or translation of any part of this work without the written permission of the copyright owners is unlawful. Request for permission or further information should be addressed to the copyright owners. Printed by Epinoia S.A. 4 Contents For the user of the D-Space service p.7 Chapter 1 p.9 1 The D-Space project p.11 Chapter 2 p.15 2 Technical description of the D-Space service p.17 2.1 The D-Space network of robotic telescopes p.17 2.2 The D-Space user interface p.21 2.2.1 Go observing p.23 2.2.2 The D-Space Resource Center p.25 2.2.3 The D-Space Communication Area p.25 Chapter 3 p.27 3 Scenarios of use p.29 3.1 Scenarios of use in formal learning settings p.29 3.2 Scenarios of Use in informal learning settings p.31 Appendix p.37 References p.47 5 6 For the user of the D-Space service The Discovery Space (D-Space) project focuses on the educational use of a network of remotely controlled telescopes. The aim of this short guide is to support the teach- ers in using the service. This Guide aims also to help users (teachers, students, astronomers, visitors of sci- ence parks and museums) to use the D-Space service in the optimum way. -
Progress in Multi-Wavelength and Multi-Messenger Observations of Blazars and Theoretical Challenges
Article Progress in Multi-Wavelength and Multi-Messenger Observations of Blazars and Theoretical Challenges Markus Böttcher Centre for Space Research, North-West University, Potchefstroom 2520, South Africa; [email protected]; Tel.: +27-18-299-2418 Received: 6 November 2018; Accepted: 9 January 2019; Published: 18 January 2019 Abstract: This review provides an overview of recent advances in multi-wavelength and multi-messenger observations of blazars, the current status of theoretical models for blazar emission, and prospects for future facilities. The discussion of observational results will focus on advances made possible through the Fermi Gamma-Ray Space Telescope and ground-based gamma-ray observatories (H.E.S.S., MAGIC, VERITAS), as well as the recent first evidence for a blazar being a source of IceCube neutrinos. The main focus of this review will be the discussion of our current theoretical understanding of blazar multi-wavelength and multi-messenger emission, in the spectral, time, and polarization domains. Future progress will be expected in particular through the development of the first X-ray polarimeter, IXPE, and the installation of the Cherenkov Telescope Array (CTA), both expected to become operational in the early to mid 2020s. Keywords: active galaxies; blazars; multi-wavelength astronomy; muti-messenger astronomy; neutrino astrophysics; polarization 1. Introduction Blazars are the class of jet-dominated, radio-loud active galactic nuclei (AGN) whose relativistic jets point close to our line of sight. Due to this viewing geometry, all emissions from a region moving 2 −1/2 with Lorentz factor G ≡ (1 − bG) , where bGc is the jet speed, along the jet, at an angle qobs with −1 respect to our line of sight, will be Doppler boosted in frequency by a factor d = (G[1 − bG cos qobs]) and in bolometric luminosity by a factor d4 with respect to quantities measured in the co-moving frame of the emission region. -
Bulletin 132 - November 2007 Node-2 Aloft
B132cover2 11/23/07 11:39 AM Page 1 www.esa.int number 132 - november 2007 Member States Etats membres Austria Allemagne Belgium Autriche Denmark Belgique Finland Danemark France Espagne Germany Finlande Greece France Ireland Grèce Italy Irlande Luxembourg Italie Netherlands Luxembourg Norway Norvège Portugal Pays-Bas SPACE FOR EUROPE Spain Portugal Sweden Royaume-Uni Switzerland Suède United Kingdom Suisse ESA bulletin 132 - november 2007 Node-2 Aloft ESA Communications ESTEC, PO Box 299, 2200 AG Noordwijk, The Netherlands Columbus Next Tel: +31 71 565-3408 Fax: +31 71 565-5433 Visit Publications at http://www.esa.int IFCb132 11/21/07 9:56 AM Page 2 european space agency Editorial/Circulation Office ESA Communications ESTEC, PO Box 299, The European Space Agency was formed out of, and took over the rights and obligations of, the two earlier European space organisations – the 2200 AG Noordwijk European Space Research Organisation (ESRO) and the European Organisation for the Development and Construction of Space Vehicle Launchers The Netherlands (ELDO). The Member States are Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Tel: +31 71 565-3408 Portugal, Spain, Sweden, Switzerland and the United Kingdom. Canada is a Cooperating State. Editors Andrew Wilson In the words of its Convention: the purpose of the Agency shall be to provide for and to promote for exclusively peaceful purposes, cooperation among Carl Walker European States in space research and technology and their -
(A)ATSR Land Surface Temperature (LST) Product (UOL LST L2) Level 2 User Guide
(A)ATSR Land Surface Temperature (LST) Product (UOL_LST_L2) Level 2 User Guide v 1.0 (A)ATSR LST L2 Product User Guide Version History Version Date Change 0.9 03/12/2013 Initial version for evaluation 1.0 17/12/2013 ESA QC recommendations applied 2 (A)ATSR LST L2 Product User Guide Table of Contents 1 Introduction ............................................................................................................................................................... 4 2 Product Description ................................................................................................................................................ 4 2.1 Scope .................................................................................................................................................................... 4 2.2 Filename Convention .................................................................................................................................... 5 2.3 File contents ..................................................................................................................................................... 6 3 Metadata ...................................................................................................................................................................... 7 3.1 Global attributes ............................................................................................................................................. 8 3.2 Variable Metadata ......................................................................................................................................... -
International Journal Remote Sensing, 2000, Vol. 21, No.17, 3383-3390
int. j. remote sensing, 2000, vol. 21, no. 17, 3383–3390 Developments in the ‘validation’ of satellite sensor products for the study of the land surface C. JUSTICE University of Virginia, Department of Environmental Sciences, University of Virginia, Charlottesville, VA 22903, USA; e-mail: [email protected] A. BELWARD Joint Research Centre, 21020 Ispra, Italy J. MORISETTE Geography Department, University of Maryland, c/o NASA-GSFC, Code 923, Greenbelt, Maryland, 20770, USA P. LEWIS Department of Geography, University of London, 26 Bedford Way, London WC1H 0AP, UK J. PRIVETTE NASA-GSFC, Code 923, Greenbelt, Maryland, 20770, USA and F. BARET INRA Bioclimatology, 84 914 Avignon, France Abstract. Increased availability of global satellite sensor data is resulting in an increase in satellite sensor products for global change research and environmental monitoring. The ensuing research and policy directives that will utilize these satellite products puts a high priority on providing statements of their accuracy. The process of quantifying the accuracy of these geophysical products is herein termed ‘validation’. This Letter provides examples of international land product ‘validation’ research and describes a new international forum for coordination within the Committee on Earth Observation Satellites (CEOS) Calibration and Validation Working Group (CVWG). 1. Introduction Researchers have long been concerned with the need to quantify the accuracy of remotely sensed land cover classi cations at the local scale but with the increase in data sets from coarse resolution sensing systems, attention has turned to the challenge of global product ‘validation’ (Justice and Townshend 1994, Robinson 1996, Justice et al. 1998a). ‘Validation’ is the process of assessing by independent means the accuracy of the data products derived from the system outputs, ‘validation’ is disting- uished from calibration which is the process of quantitatively de ning the system response to known, controlled signal inputs (WWW 1). -
Multi-Band Intra-Night Optical Variability of BL Lacertae
Article Multi-Band Intra-Night Optical Variability of BL Lacertae Haritma Gaur 1,*, Alok C. Gupta 2, Rumen Bachev 3, Anton Strigachev 3, Evgeni Semkov 3, Paul J. Wiita 4,5, Minfeng Gu 1 and Sunay Ibryamov 6 1 Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, China; [email protected] 2 Aryabhatta Research Institute of Observational Sciences (ARIES), Manora Peak, Nainital 263002, India; [email protected] 3 Institute of Astronomy and National Astronomical Observatory, Bulgarian Academy of Sciences, 72 Tsarigradsko Shosse Blvd., 1784 Sofia, Bulgaria; [email protected] (R.B); [email protected] (A.S); [email protected] (E.S) 4 Department of Physics, The College of New Jersey, P.O. Box 7718, Ewing, NJ 08628-0718, USA; [email protected] 5 Kavli Institute for Particle Astrophysics and Cosmology, SLAC, 2575 Sand Hill Rd, Menlo Park, CA 94025, USA 6 Department of Theoretical and Applied Physics, Faculty of Natural Sciences, University of Shumen, 115, Universitetska Str., 9712 Shumen, Bulgaria; [email protected] * Correspondence: [email protected] Received: 30 October 2017; Accepted: 5 December 2017; Published: 8 December 2017 Abstract: We monitored BL Lacertae frequently during 2014–2016 when it was generally in a high state. We searched for intra-day variability for 43 nights using quasi-simultaneous measurements in the B, V, R, and I bands (totaling 143 light curves); the typical sampling interval was about eight minutes. On hour-like timescales, BL Lac exhibited significant variations during 13 nights in various optical bands. -
Optical Counterpart to Swift J0243. 6+ 6124
Astronomy & Astrophysics manuscript no. ms c ESO 2020 September 23, 2020 Optical counterpart to Swift J0243.6+6124 P. Reig1, 2, J. Fabregat3, and J. Alfonso-Garzón4 1 Institute of Astrophysics, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece 2 Physics Department, University of Crete, 71003 Heraklion, Greece e-mail: [email protected] 3 Observatorio Astronómico, Universidad de Valencia, Catedrático José Beltrán 2, 46980 Paterna, Spain 4 Centro de Astrobiología-Departamento de Astrofísica (CSIC-INTA), Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Spain Received ; accepted ABSTRACT Context. Swift J0243.6+6124 is a unique system. It is the first and only ultra-luminous X-ray source in our Galaxy. It is the first and only high-mass Be X-ray pulsar showing radio jet emission. It was discovered during a giant X-ray outburst in October 2017. While there are numerous studies in the X-ray band, very little is known about the optical counterpart. Aims. Our aim is to characterize the variability timescales in the optical and infrared bands in order to understand the nature of this intriguing system. Methods. We performed optical spectroscopic observations to determine the spectral type. Long-term photometric light curves to- gether with the equivalent width of the Hα line were used to monitor the state of the circumstellar disk. We used BVRI photometry to estimate the interstellar absorption and distance to the source. Continuous photometric monitoring in the B and V bands allowed us to search for intra-night variability. Results. The optical counterpart to Swift J0243.6+6124 is a V = 12.9, O9.5Ve star, located at a distance of ∼ 5 kpc.