Observations of the Sun at Vacuum-Ultraviolet Wavelengths from Space. Part II: Results and Interpretations
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A Deep Learning Framework for Solar Phenomena Prediction
FlareNet: A Deep Learning Framework for Solar Phenomena Prediction FDL 2017 Solar Storm Team: Sean McGregor1, Dattaraj Dhuri1,2, Anamaria Berea1,3, and Andrés Muñoz-Jaramillo1,4 1NASA’s 2017 Frontier Development Laboratory 2Tata Institute of Fundamental Research (TIFR), Mumbai, India 3Center for Complexity in Business, University of Maryland, College Park, MD, USA 4SouthWest Research Institute, Boulder, CO, USA Abstract Solar activity can interfere with the normal operation of GPS satellites, the power grid, and space operations, but inadequate predictive models mean we have little warning for the arrival of newly disruptive solar activity. Petabytes of data col- lected from satellite instruments aboard the Solar Dynamics Observatory (SDO) provide a high-cadence, high-resolution, and many-channeled dataset of solar phenomena. Several challenging deep learning problems may be derived from the data, including space weather forecasting (i.e., solar flares, solar energetic particles, and coronal mass ejections). This work introduces a software framework, FlareNet, for experimentation within these problems. FlareNet includes compo- nents for the downloading and management of SDO data, visualization, and rapid experimentation. The system architecture is built to enable collaboration between heliophysicists and machine learning researchers on the topics of image regres- sion, image classification, and image segmentation. We specifically highlight the problem of solar flare prediction and offer insights from preliminary experiments. 1 Introduction The violent release of solar magnetic energy – collectively referred to as “space weather" – is responsible for a variety of phenomena that can disrupt technological assets. In particular, solar flares (sudden brightenings of the solar corona) and coronal mass ejections (CMEs; the violent release of solar plasma) can disrupt long-distance communications, reduce Global Positioning System (GPS) accuracy, degrade satellites, and disrupt the power grid [5]. -
Solar and Space Physics: a Science for a Technological Society
Solar and Space Physics: A Science for a Technological Society The 2013-2022 Decadal Survey in Solar and Space Physics Space Studies Board ∙ Division on Engineering & Physical Sciences ∙ August 2012 From the interior of the Sun, to the upper atmosphere and near-space environment of Earth, and outwards to a region far beyond Pluto where the Sun’s influence wanes, advances during the past decade in space physics and solar physics have yielded spectacular insights into the phenomena that affect our home in space. This report, the final product of a study requested by NASA and the National Science Foundation, presents a prioritized program of basic and applied research for 2013-2022 that will advance scientific understanding of the Sun, Sun- Earth connections and the origins of “space weather,” and the Sun’s interactions with other bodies in the solar system. The report includes recommendations directed for action by the study sponsors and by other federal agencies—especially NOAA, which is responsible for the day-to-day (“operational”) forecast of space weather. Recent Progress: Significant Advances significant progress in understanding the origin from the Past Decade and evolution of the solar wind; striking advances The disciplines of solar and space physics have made in understanding of both explosive solar flares remarkable advances over the last decade—many and the coronal mass ejections that drive space of which have come from the implementation weather; new imaging methods that permit direct of the program recommended in 2003 Solar observations of the space weather-driven changes and Space Physics Decadal Survey. For example, in the particles and magnetic fields surrounding enabled by advances in scientific understanding Earth; new understanding of the ways that space as well as fruitful interagency partnerships, the storms are fueled by oxygen originating from capabilities of models that predict space weather Earth’s own atmosphere; and the surprising impacts on Earth have made rapid gains over discovery that conditions in near-Earth space the past decade. -
Solar Chromospheric Flares
Solar Chromospheric Flares A proposal for an ISSI International Team Lyndsay Fletcher (Glasgow) and Jana Kasparova (Ondrejov) Summary Solar flares are the most energetic energy release events in the solar system. The majority of energy radiated from a flare is produced in the solar chromosphere, the dynamic interface between the Sun’s photosphere and corona. Despite solar flare radiation having been known for decades to be principally chromospheric in origin, the attention of the community has re- cently been strongly focused on the corona. Progress in understanding chromospheric flare physics and the diagnostic potential of chromospheric observations has stagnated accord- ingly. But simultaneously, motivated by the available chromospheric observations, the ‘stan- dard flare model’, of energy transport by an electron beam from the corona, is coming under scrutiny. With this team we propose to return to the chromosphere for basic understanding. The present confluence of high quality chromospheric flare observations and sophisticated numerical simulation techniques, as well as the prospect of a new generation of missions and telescopes focused on the chromosphere, makes it an excellent time for this endeavour. The international team of experts in the theory and observation of solar chromospheric flares will focus on the question of energy deposition in solar flares. How can multi-wavelength, high spatial, spectral and temporal resolution observations of the flare chromosphere from space- and ground-based observatories be interpreted in the context of detailed modeling of flare radiative transfer and hydrodynamics? With these tools we can pin down the depth in the chromosphere at which flare energy is deposited, its time evolution and the response of the chromosphere to this dramatic event. -
Manual Ls40tha H-Alpha Solar-Telescope
Manual LS40THa H-alpha Solar-Telescope Telescope for solar observation in the H-Alpha wavelength. The H-alpha wavelength is the most impressive way to observe the sun, here prominences at the solar edge become visible, filaments and flares on the surface, and much more. Included Contents: - LS40THa telescope - H-alpha unit with tilt-tuning - Blocking-filter B500, B600, or B1200 - 1.25 inch Helical focuser - Dovetail bar (GP level) for installing at astronomical mounts - 1/4-20 tapped base (standard thread for photo-tripods) inside the dovetail for installing at photo-tripods - Sol-searcher Please note: Please keep the foam insert from the delivery box. The optionally available transport-case for the LS40THa (item number 0554010) is not supplied without such a foam insert, the original foam insert from the delivery box fits exactly into this transport-case. Congratulations and thank you for purchasing the LS40THa telescope from Lunt Solar Systems! The easy handling makes this telescope ideal for starting H-Alpha solar observation. Due to its compact dimensions it is also a good travel telescope for the experienced solar observers. Safety Information: There are inherent dangers when looking at the Sun thru any instrument. Lunt Solar Systems has taken your safety very seriously in the design of our systems. With safety being the highest priority we ask that you read and understand the operation of your telescope or filter system prior to use. Never attempt to disassemble the telescope! Do not use your system if it is in someway compromised due to mishandling or damage. Please contact our customer service with any questions or concerns regarding the safe use of your instrument. -
Formation and Evolution of Coronal Rain Observed by SDO/AIA on February 22, 2012?
A&A 577, A136 (2015) Astronomy DOI: 10.1051/0004-6361/201424101 & c ESO 2015 Astrophysics Formation and evolution of coronal rain observed by SDO/AIA on February 22, 2012? Z. Vashalomidze1;2, V. Kukhianidze2, T. V. Zaqarashvili1;2, R. Oliver3, B. Shergelashvili1;2, G. Ramishvili2, S. Poedts4, and P. De Causmaecker5 1 Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, 8042 Graz, Austria e-mail: [teimuraz.zaqarashvili]@oeaw.ac.at 2 Abastumani Astrophysical Observatory at Ilia State University, Cholokashvili Ave.3/5, Tbilisi, Georgia 3 Departament de Física, Universitat de les Illes Balears, 07122, Palma de Mallorca, Spain 4 Dept. of Mathematics, Centre for Mathematical Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven, Belgium 5 Dept. of Computer Science, CODeS & iMinds-iTEC, KU Leuven, KULAK, E. Sabbelaan 53, 8500 Kortrijk, Belgium Received 30 April 2014 / Accepted 25 March 2015 ABSTRACT Context. The formation and dynamics of coronal rain are currently not fully understood. Coronal rain is the fall of cool and dense blobs formed by thermal instability in the solar corona towards the solar surface with acceleration smaller than gravitational free fall. Aims. We aim to study the observational evidence of the formation of coronal rain and to trace the detailed dynamics of individual blobs. Methods. We used time series of the 171 Å and 304 Å spectral lines obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) above active region AR 11420 on February 22, 2012. Results. Observations show that a coronal loop disappeared in the 171 Å channel and appeared in the 304 Å line more than one hour later, which indicates a rapid cooling of the coronal loop from 1 MK to 0.05 MK. -
Mechanisms of Chromospheric and Coronal Heating a NIXT Solar X-Ray Photo in the Fe XVI Line at 63.5 a Taken on a Rocket Flight on 11 Sept
Mechanisms of Chromospheric and Coronal Heating A NIXT solar X-ray photo in the Fe XVI line at 63.5 A taken on a rocket flight on 11 Sept. 1989 by Leon Golub (see the article on p. 115 of this book) P. Ultnschneider E. R. Priest R. Rosner (Eds.) Mechanisms of Chromospheric and Coronal Heating Proceedings of the International Conference, Heidelberg, 5-8 lune 1990 With 260 Figures Springer-Verlag Berlin Heidelberg GmbH Professor Dr. Peter Ulmschneider Institut für Theoretische Astrophysik. Im Neuenheimer Feld 561. D-69oo Heidelberg. Fed. Rep. ofGermany Professor Dr. Eric R. Priest University of St. Andrews. The Mathematical Institute North Haugh. St. Andrews KY16 9SS. Great Britain Professor Dr. Robert Rosner E. Fermi Institute and Dept. of Astronomy and Astrophysics. 5640 S Ellis Ave .• Chicago. IL 60637. USA Cover picture: In this scenario by Chitre and Davila (see the article on p.402 of this book) acoustic waves shake coronal magnetic loops and get resonantly absorbed in the loop. ISBN 978-3-642-87457-4 ISBN 978-3-642-87455-0 (eBook) DOI 10.I007/978-3-642-87455-0 This work is subject to copyright. All rights are reserved. whether the whole or part of the material is concerned. specifically the rights of translation. reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in other ways, and storage in data banks. Duplication ofthis publication or parts thereofis only per mitted underthe provisions ofthe German Copyright Law ofSeptember9, 1965. in its current version, and a copy right fee must always be paid. Violations fall under the prosecution act ofthe German Copyright Law. -
Space Weather Lecture 2: the Sun and the Solar Wind
Space Weather Lecture 2: The Sun and the Solar Wind Elena Kronberg (Raum 442) [email protected] Elena Kronberg: Space Weather Lecture 2: The Sun and the Solar Wind 1 / 39 The radiation power is '1.5 kW·m−2 at the distance of the Earth The Sun: facts Age = 4.5×109 yr Mass = 1.99×1030 kg (330,000 Earth masses) Radius = 696,000 km (109 Earth radii) Mean distance from Earth (1AU) = 150×106 km (215 solar radii) Equatorial rotation period = '25 days Mass loss rate = 109 kg·s−1 It takes sunlight 8 min to reach the Earth Elena Kronberg: Space Weather Lecture 2: The Sun and the Solar Wind 2 / 39 The Sun: facts Age = 4.5×109 yr Mass = 1.99×1030 kg (330,000 Earth masses) Radius = 696,000 km (109 Earth radii) Mean distance from Earth (1AU) = 150×106 km (215 solar radii) Equatorial rotation period = '25 days Mass loss rate = 109 kg·s−1 It takes sunlight 8 min to reach the Earth The radiation power is '1.5 kW·m−2 at the distance of the Earth Elena Kronberg: Space Weather Lecture 2: The Sun and the Solar Wind 2 / 39 The Solar interior Core: 1H +1 H !2 H + e+ + n + 0.42 MeV 1H +2 He !3 H + g + 5.5 MeV 3He +3 He !4 He + 21H + 12.8 MeV The radiative zone: electromagnetic radiation transports energy outwards The convection zone: energy is transported by convection The photosphere – layer which emits visible light The chromosphere is the Sun’s atmosphere. -
Multi-Spacecraft Analysis of the Solar Coronal Plasma
Multi-spacecraft analysis of the solar coronal plasma Von der Fakultät für Elektrotechnik, Informationstechnik, Physik der Technischen Universität Carolo-Wilhelmina zu Braunschweig zur Erlangung des Grades einer Doktorin der Naturwissenschaften (Dr. rer. nat.) genehmigte Dissertation von Iulia Ana Maria Chifu aus Bukarest, Rumänien eingereicht am: 11.02.2015 Disputation am: 07.05.2015 1. Referent: Prof. Dr. Sami K. Solanki 2. Referent: Prof. Dr. Karl-Heinz Glassmeier Druckjahr: 2016 Bibliografische Information der Deutschen Nationalbibliothek Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar. Dissertation an der Technischen Universität Braunschweig, Fakultät für Elektrotechnik, Informationstechnik, Physik ISBN uni-edition GmbH 2016 http://www.uni-edition.de © Iulia Ana Maria Chifu This work is distributed under a Creative Commons Attribution 3.0 License Printed in Germany Vorveröffentlichung der Dissertation Teilergebnisse aus dieser Arbeit wurden mit Genehmigung der Fakultät für Elektrotech- nik, Informationstechnik, Physik, vertreten durch den Mentor der Arbeit, in folgenden Beiträgen vorab veröffentlicht: Publikationen • Mierla, M., Chifu, I., Inhester, B., Rodriguez, L., Zhukov, A., 2011, Low polarised emission from the core of coronal mass ejections, Astronomy and Astrophysics, 530, L1 • Chifu, I., Inhester, B., Mierla, M., Chifu, V., Wiegelmann, T., 2012, First 4D Recon- struction of an Eruptive Prominence -
The Solar Optical Telescope
NASATM109240 The Solar Optical Telescope (NAS.A- TM- 109240) TELESCOPE (NASA) NASA The Solar Optical Telescope is shown in the Sun-pointed configuration, mounted on an Instrument Pointing System which is attached to a Spacelab Pallet riding in the Shuttle Orbiter's Cargo Bay. The Solar Optical Telescope - will study the physics of the Sun on the scale at which many of the important physical processes occur - will attain a resolution of 73km on the Sun or 0.1 arc seconds of angular resolution 1 SOT-I GENERAL CONFIGURATION ARTICULATED VIEWPOINT DOOR PRIMARY MIRROR op IPS SENSORS WAVEFRONT SENSOR - / i— VENT LIGHT TUNNEL-7' ,—FINAL I 7 I FOCUS IPS INTERFACE E-BOX SHELF GREGORIAN POD---' U (1 of 4) HEAT REJECTION MIRROR-S 1285'i Why is the Solar Optical Telescope Needed? There may be no single object in nature that mankind For exrmple, the hedii nq and expns on of the solar wind U 2 is more dependent upon than the Sun, unless it is the bathes the Earth in solar plasma is ultimately attributable to small- Earth itself. Without the Sun's radiant energy, there scale processes that occur close to the solar surface. Only by would be no life on Earth as we know it. Even our prim- observing the underlying processes on the small scale afforded ary source of energy today, fossil fuels, is available be- by the Solar Optical Telescope can we hope to gain a profound cause of solar energy millions of years ago; and when understanding of how the Sun transfers its radiant and particle mankind succeeds in taming the nuclear reaction that energy through the different atmospheric regions and ultimately converts hydrogen into helium for our future energy to our Earth. -
The 2015 Senior Review of the Heliophysics Operating Missions
The 2015 Senior Review of the Heliophysics Operating Missions June 11, 2015 Submitted to: Steven Clarke, Director Heliophysics Division, Science Mission Directorate Jeffrey Hayes, Program Executive for Missions Operations and Data Analysis Submitted by the 2015 Heliophysics Senior Review panel: Arthur Poland (Chair), Luca Bertello, Paul Evenson, Silvano Fineschi, Maura Hagan, Charles Holmes, Randy Jokipii, Farzad Kamalabadi, KD Leka, Ian Mann, Robert McCoy, Merav Opher, Christopher Owen, Alexei Pevtsov, Markus Rapp, Phil Richards, Rodney Viereck, Nicole Vilmer. i Executive Summary The 2015 Heliophysics Senior Review panel undertook a review of 15 missions currently in operation in April 2015. The panel found that all the missions continue to produce science that is highly valuable to the scientific community and that they are an excellent investment by the public that funds them. At the top level, the panel finds: • NASA’s Heliophysics Division has an excellent fleet of spacecraft to study the Sun, heliosphere, geospace, and the interaction between the solar system and interstellar space as a connected system. The extended missions collectively contribute to all three of the overarching objectives of the Heliophysics Division. o Understand the changing flow of energy and matter throughout the Sun, Heliosphere, and Planetary Environments. o Explore the fundamental physical processes of space plasma systems. o Define the origins and societal impacts of variability in the Earth/Sun System. • All the missions reviewed here are needed in order to study this connected system. • Progress in the collection of high quality data and in the application of these data to computer models to better understand the physics has been exceptional. -
Astronomy Astrophysics
A&A 424, 289–300 (2004) Astronomy DOI: 10.1051/0004-6361:20040403 & c ESO 2004 Astrophysics Dynamics of solar coronal loops II. Catastrophic cooling and high-speed downflows D. A. N. Müller1,2, H. Peter1, and V. H. Hansteen2 1 Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, 79104 Freiburg, Germany e-mail: [email protected];[email protected] 2 Institute of Theoretical Astrophysics, University of Oslo, PO Box 1029, Blindern 0315, Oslo, Norway e-mail: [email protected] Received 7 March 2004 / Accepted 14 May 2004 Abstract. This work addresses the problem of plasma condensation and “catastrophic cooling” in solar coronal loops. We have carried out numerical calculations of coronal loops and find several classes of time-dependent solutions (static, periodic, irregular), depending on the spatial distribution of a temporally constant energy deposition in the loop. Dynamic loops exhibit recurrent plasma condensations, accompanied by high-speed downflows and transient brightenings of transition region lines, in good agreement with features observed with TRACE. Furthermore, these results also offer an explanation for the recent EIT observations of De Groof et al. (2004) of moving bright blobs in large coronal loops. In contrast to earlier models, we suggest that the process of catastrophic cooling is not initiated by a drastic decrease of the total loop heating but rather results from a loss of equilibrium at the loop apex as a natural consequence of heating concentrated at the footpoints of the loop, but constant in time. Key words. Sun: corona – Sun: transition region – Sun: UV radiation 1. Introduction observations, compatible with “dramatic evacuation” of active region loops triggered by rapid, radiation dominated cooling. -
Arxiv:1708.06781V1 [Astro-Ph.SR] 22 Aug 2017 Very Complex Region That Is Difficult to Directly Diagnose
Draft version August 24, 2017 Preprint typeset using LATEX style emulateapj v. 12/16/11 TWO-DIMENSIONAL RADIATIVE MAGNETOHYDRODYNAMIC SIMULATIONS OF PARTIAL IONIZATION IN THE CHROMOSPHERE. II. DYNAMICS AND ENERGETICS OF THE LOW SOLAR ATMOSPHERE Juan Mart´ınez-Sykora1,2, Bart De Pontieu2,3, Mats Carlsson3, Viggo H. Hansteen3,2, Daniel Nobrega-Siverio´ 4,5, and Boris V. Gudiksen3 1 Bay Area Environmental Research Institute, Petaluma, CA 94952, USA 2 Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304, USA 3 Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo, Norway 4 Instituto de Astrof´ısicade Canarias, 38200 La Laguna (Tenerife), Spain and 5 Department of Astrophysics, Universidad de La Laguna, E-38200 La Laguna (Tenerife), Spain Draft version August 24, 2017 ABSTRACT We investigate the effects of interactions between ions and neutrals on the chromosphere and over- lying corona using 2.5D radiative MHD simulations with the Bifrost code. We have extended the code capabilities implementing ion-neutral interaction effects using the Generalized Ohm's Law, i.e., we include the Hall term and the ambipolar diffusion (Pedersen dissipation) in the induction equation. Our models span from the upper convection zone to the corona, with the photosphere, chromosphere and transition region partially ionized. Our simulations reveal that the interactions between ionized particles and neutral particles have important consequences for the magneto-thermodynamics of these modeled layers: 1) ambipolar diffusion increases the temperature in the chromosphere; 2) sporadically the horizontal magnetic field in the photosphere is diffused into the chromosphere due to the large ambipolar diffusion; 3) ambipolar diffusion concentrates electrical currents leading to more violent jets and reconnection processes, resulting in 3a) the formation of longer and faster spicules, 3b) heating of plasma during the spicule evolution, and 3c) decoupling of the plasma and magnetic field in spicules.