Dear Science Educator: Because of Its Relationship to the Sun, Solar
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Solar Modulation Effect on Galactic Cosmic Rays
Solar Modulation Effect On Galactic Cosmic Rays Cristina Consolandi – University of Hawaii at Manoa Nov 14, 2015 Galactic Cosmic Rays Voyager in The Galaxy The Sun The Sun is a Star. It is a nearly perfect spherical ball of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. 3 The Sun & The Heliosphere The heliosphere contains the solar system GCR may penetrate the Heliosphere and propagate trough it by following the Sun's magnetic field lines. 4 The Heliosphere Boundaries The Heliosphere is the region around the Sun over which the effect of the solar wind is extended. 5 The Solar Wind The Solar Wind is the constant stream of charged particles, protons and electrons, emitted by the Sun together with its magnetic field. 6 Solar Wind & Sunspots Sunspots appear as dark spots on the Sun’s surface. Sunspots are regions of strong magnetic fields. The Sun’s surface at the spot is cooler, making it looks darker. It was found that the stronger the solar wind, the higher the sunspot number. The sunspot number gives information about 7 the Sun activity. The 11-year Solar Cycle The solar Wind depends on the Sunspot Number Quiet At maximum At minimum of Sun Spot of Sun Spot Number the Number the sun is Active sun is Quiet Active! 8 The Solar Wind & GCR The number of Galactic Cosmic Rays entering the Heliosphere depends on the Solar Wind Strength: the stronger is the Solar wind the less probable would be for less energetic Galactic Cosmic Rays to overcome the solar wind! 9 How do we measure low energy GCR on ground? With Neutron Monitors! The primary cosmic ray has enough energy to start a cascade and produce secondary particles. -
And Ground-Based Observations of Pulsating Aurora
University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 2010 Space- and ground-based observations of pulsating aurora Sarah Jones University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation Jones, Sarah, "Space- and ground-based observations of pulsating aurora" (2010). Doctoral Dissertations. 597. https://scholars.unh.edu/dissertation/597 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. SPACE- AND GROUND-BASED OBSERVATIONS OF PULSATING AURORA BY SARAH JONES B.A. in Physics, Dartmouth College 2004 DISSERTATION Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Physics May, 2010 UMI Number: 3470104 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. UMT Dissertation Publishing UMI 3470104 Copyright 2010 by ProQuest LLC. All rights reserved. This edition of the work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 This dissertation has been examined and approved. -
O + Escape During the Extreme Space Weather Event of 4-10 September
O + Escape During the Extreme Space Weather Event of 4-10 September 2017 Audrey Schillings, Hans Nilsson, Rikard Slapak, Peter Wintoft, Masatoshi Yamauchi, Magnus Wik, Iannis Dandouras, Chris Carr To cite this version: Audrey Schillings, Hans Nilsson, Rikard Slapak, Peter Wintoft, Masatoshi Yamauchi, et al.. O + Es- cape During the Extreme Space Weather Event of 4-10 September 2017. Journal of Space Weather and Space Climate, EDP sciences, 2018, 16 (9), pp.1363-1376. 10.1029/2018SW001881. hal-02408153 HAL Id: hal-02408153 https://hal.archives-ouvertes.fr/hal-02408153 Submitted on 12 Dec 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. SPACE WEATHER, VOL. ???, XXXX, DOI:10.1002/, + 1 O escape during the extreme space weather event of 2 September 4–10, 2017 Audrey Schillings,1,2 Hans Nilsson,1,2 Rikard Slapak,3 Peter Wintoft,4 Masatoshi Yamauchi,1 Magnus Wik,4 Iannis Dandouras,5 and Chris M. Carr,6 Corresponding author: Audrey Schillings, Swedish Institute of Space Physics, Kiruna, Sweden. ([email protected]) 1Swedish Institute of Space Physics, Kiruna, Sweden. 2Division of Space Technology, Lule˚a University of Technology, Kiruna, Sweden. -
A Three-Dimensional Time-Dependent Model of the Polar Wind
JOURNAL OF G EOPHYSICAL RESE ARCH. VO L. 94 . NO . A7. PAG E 8973-8991 , J ULY I. 1989 A Three-Dimensional Time-Dependent Model of the Polar Wind R. W. SCHUNK AND J. J. SOJKA Center for Atmospheric and Space Sciences, Utah State University, Logan A time-dependent global model of the polar wind was used to study transient polar wind per turbations during changing magnetospheric conditions. The model calculates three-dimensional distributions for the NO+, ot, Nt, N+ and 0 + densities and the ion and electron tempera tures from diffusion and heat conduction equations at altitudes between 120 and 800 km. At altitudes above 500 km, the time-dependent nonlinear hydrodynamic equations for 0 + and H+ are solved self-consistently with the ionospheric equations. The model takes account of supersonic ion outflow, shock formation, and ion energization during a plasma expansion event. During the simulation, the magnetic activity level changed from quiet to active and back to quiet again over a 4.5-hour period. The study indicates the following: (1) Plasma pressure changes due to Te , Ti or electron density variations produce perturbations in the polar wind. In particular, plasma flux tube motion through the auroral oval and high electric field regions produces transient large-scale ion upflows and downflows. At certain times and in certain regions both inside and outside the auroral oval, H+-O+ counterstreaming can occur, (2) The density structure in the polar wind is considerably more complicated than in the ionosphere because of both horizontal plasma convec tion and changing vertical propagation speeds due to spatially varying ionospheric temperatures, (3) During increasing magnetic activity, there is an overall increase in Te , Ti and the electron density in the F-region, but there is a time delay in the buildup of the electron density that is . -
Geomagnetic Disturbance Intensity Dependence on the Universal Timing of the Storm Peak
Geomagnetic disturbance intensity dependence on the universal timing of the storm peak R.M. Katus1,3,2, M.W. Liemohn2, A.M. Keesee3, T.J. Immel4, R. Ilie2, D. T. Welling2, N. Yu. Ganushkina5,2, N.J. Perlongo2, and A. J. Ridley2 1. Department of Mathematics, Eastern Michigan University, Ypsilanti, MI, USA 2. Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI, USA 3. Department of Physics and Astronomy, West Virginia University, Morgantown, WVU, USA 4. Space Sciences Laboratory, University of California, Berkeley, CA, USA 5. Finnish Meteorological Institute, Helsinki, Finland Submitted to: Journal of Geophysical Research Corresponding author email: [email protected] AGU index terms: 2730 Magnetosphere: inner 2788 Magnetic storms and substorms (4305, 7954) 4305 Space weather (2101, 2788, 7900) 4318 Statistical analysis (1984, 1986) 7954 Magnetic storms (2788) Keywords: Geomagnetic indices, ground-based magnetometers, Longitudinal dependence, magnetic storms, space weather Key points: • We statistically examine storm-time solar wind and geophysical data as a function of UT of the storm peak. • There is a significant UT dependence to large storms; larger storms occur with a peak near 02 UT. • The difference in storm magnitude is caused by substorm activity and not by solar wind driving. This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/2016JA022967 This article is protected by copyright. All rights reserved. -
Activity - Sunspot Tracking
JOURNEY TO THE SUN WITH THE NATIONAL SOLAR OBSERVATORY Activity - SunSpot trAcking Adapted by NSO from NASA and the European Space Agency (ESA). https://sohowww.nascom.nasa.gov/classroom/docs/Spotexerweb.pdf / Retrieved on 01/23/18. Objectives In this activity, students determine the rate of the Sun’s rotation by tracking and analyzing real solar data over a period of 7 days. Materials □ Student activity sheet □ Calculator □ Pen or pencil bacKgrOund In this activity, you’ll observe and track sunspots across the Sun, using real images from the National Solar Observatory’s: Global Oscillation Network Group (GONG). This can also be completed with data students gather using www.helioviewer.org. See lesson 4 for instructions. GONG uses specialized telescope cameras to observe diferent layers of the Sun in diferent wavelengths of light. Each layer has a diferent story to tell. For example, the chromosphere is a layer in the lower solar atmosphere. Scientists observe this layer in H-alpha light (656.28nm) to study features such as flaments and prominences, which are clearly visible in the chromosphere. For the best view of sunspots, GONG looks to the photosphere. The photosphere is the lowest layer of the Sun’s atmosphere. It’s the layer that we consider to be the “surface” of the Sun. It’s the visible portion of the Sun that most people are familiar with. In order to best observe sunspots, scientists use photospheric light with a wavelength of 676.8nm. The images that you will analyze in this activity are of the solar photosphere. The data gathered in this activity will allow you to determine the rate of the Sun’s rotation. -
Ionospheric Response to Traveling Convection Twin Vortices
GEOPHYSICAL RESEARCH LETTERS, VOL. 21, NO. 17, PAGES 1759-1762, AUGUST 15,1994 JonoS heric response to traveling convection twin vortices It W. Schunk, L. Zhu, and J. J. Sojka Center for Atmo pheric and Space Sciences, Utah State University, Logan, Utah 84322-4405 Abstract. Traveling convection twin vortices have been move in the antisunward direction for a period of several hours, bserved for everal years. At ionospheric altitudes, the twin with about a 15-minute time interval between vortices. ~ortiCes correspond to spatially localized, transient structures Mounting evidence indicates that the twin vortices occur on embedded in large-scale background convection pattern. The closed magnetic field lines and most likely those field lines convection vortices are typically observed in the morning and that connect to the low-latitude boundary layers (LLBL) evening regions. They are aligned predominantly in the east [Heikkila et ai., 1989; McHenry et ai., 1990a]. At present, the west direction and have a horizontal extent of from 500-1000 prevailing view is that the twin vortices are not a result of flux km. Associated with the twin vortices are enhanced electric transfer events at the dayside magnetopause, but their exact fields, particle precipitation, and an upward/downward field cause is still controversial. Friis-Christensen et ai. [1988] aligned cu rrent pair. Once formed, the twin vortex structures suggested that the traveling vortices are due to sudden changes propagate in the tail ward direction at speeds of several km/s, in the solar wind dynamic pressure or the interplanetary but they weaken as they propagate and only last for about 10- magnetic field (lMF). -
Jets Downstream of Collisionless Shocks
Space Sci Rev (2018) 214:81 https://doi.org/10.1007/s11214-018-0516-3 Jets Downstream of Collisionless Shocks Ferdinand Plaschke1,2 · Heli Hietala3 · Martin Archer4 · Xóchitl Blanco-Cano5 · Primož Kajdicˇ5 · Tomas Karlsson6 · Sun Hee Lee7 · Nojan Omidi8 · Minna Palmroth9,10 · Vadim Roytershteyn11 · Daniel Schmid12 · Victor Sergeev13 · David Sibeck7 Received: 19 December 2017 / Accepted: 2 June 2018 / Published online: 21 June 2018 © The Author(s) 2018 Abstract The magnetosheath flow may take the form of large amplitude, yet spatially local- ized, transient increases in dynamic pressure, known as “magnetosheath jets” or “plasmoids” among other denominations. Here, we describe the present state of knowledge with respect to such jets, which are a very common phenomenon downstream of the quasi-parallel bow shock. We discuss their properties as determined by satellite observations (based on both case and statistical studies), their occurrence, their relation to solar wind and foreshock con- ditions, and their interaction with and impact on the magnetosphere. As carriers of plasma and corresponding momentum, energy, and magnetic flux, jets bear some similarities to bursty bulk flows, which they are compared to. Based on our knowledge of jets in the near Earth environment, we discuss the expectations for jets occurring in other planetary and B F. Plaschke [email protected] 1 Space Research Institute, Austrian Academy of Sciences, Graz, Austria 2 Present address: Institute of Physics, University of Graz, Graz, Austria 3 Department of -
Cmes, Solar Wind and Sun-Earth Connections: Unresolved Issues
CMEs, solar wind and Sun-Earth connections: unresolved issues Rainer Schwenn Max-Planck-Institut für Sonnensystemforschung, Katlenburg-Lindau, Germany [email protected] In recent years, an unprecedented amount of high-quality data from various spaceprobes (Yohkoh, WIND, SOHO, ACE, TRACE, Ulysses) has been piled up that exhibit the enormous variety of CME properties and their effects on the whole heliosphere. Journals and books abound with new findings on this most exciting subject. However, major problems could still not be solved. In this Reporter Talk I will try to describe these unresolved issues in context with our present knowledge. My very personal Catalog of ignorance, Updated version (see SW8) IAGA Scientific Assembly in Toulouse, 18-29 July 2005 MPRS seminar on January 18, 2006 The definition of a CME "We define a coronal mass ejection (CME) to be an observable change in coronal structure that occurs on a time scale of a few minutes and several hours and involves the appearance (and outward motion, RS) of a new, discrete, bright, white-light feature in the coronagraph field of view." (Hundhausen et al., 1984, similar to the definition of "mass ejection events" by Munro et al., 1979). CME: coronal -------- mass ejection, not: coronal mass -------- ejection! In particular, a CME is NOT an Ejección de Masa Coronal (EMC), Ejectie de Maså Coronalå, Eiezione di Massa Coronale Éjection de Masse Coronale The community has chosen to keep the name “CME”, although the more precise term “solar mass ejection” appears to be more appropriate. An ICME is the interplanetry counterpart of a CME 1 1. -
Coronal Holes
Living Rev. Solar Phys., 6, (2009), 3 LIVING REVIEWS http://www.livingreviews.org/lrsp-2009-3 in solar physics Coronal Holes Steven R. Cranmer Harvard-Smithsonian Center for Astrophysics 60 Garden Street, Mail Stop 50 Cambridge, MA 02138, U.S.A. email: [email protected] http://www.cfa.harvard.edu/~scranmer/ Accepted on 15 September 2009 Published on 29 September 2009 Abstract Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind. This paper reviews measurements of the plasma properties in coronal holes and how these measurements are used to reveal details about the physical processes that heat the solar corona and accelerate the solar wind. It is still unknown to what extent the solar wind is fed by flux tubes that remain open (and are energized by footpoint-driven wave-like fluctuations), and to what extent much of the mass and energy is input intermittently from closed loops into the open-field regions. Evidence for both paradigms is summarized in this paper. Special emphasis is also given to spectroscopic and coronagraphic measurements that allow the highly dynamic non-equilibrium evolution of the plasma to be followed as the asymptotic conditions in interplanetary space are established in the extended corona. For example, the importance of kinetic plasma physics and turbulence in coronal holes has been affirmed by surprising measurements from the UVCS instrument on SOHO that heavy ions are heated to hundreds of times the temperatures of protons and electrons. -
Critical Thinking Activity: Getting to Know Sunspots
Student Sheet 1 CRITICAL THINKING ACTIVITY: GETTING TO KNOW SUNSPOTS Our Sun is not a perfect, constant source of heat and light. As early as 28 B.C., astronomers in ancient China recorded observations of the movements of what looked like small, changing dark patches on the surface of the Sun. There are also some early notes about sunspots in the writings of Greek philosophers from the fourth century B.C. However, none of the early observers could explain what they were seeing. The invention of the telescope by Dutch craftsmen in about 1608 changed astronomy forever. Suddenly, European astronomers could look into space, and see unimagined details on known objects like the moon, sun, and planets, and discovering planets and stars never before visible. No one is really sure who first discovered sunspots. The credit is usually shared by four scientists, including Galileo Galilei of Italy, all of who claimed to have noticed sunspots sometime in 1611. All four men observed sunspots through telescopes, and made drawings of the changing shapes by hand, but could not agree on what they were seeing. Some, like Galileo, believed that sunspots were part of the Sun itself, features like spots or clouds. But other scientists, believed the Catholic Church's policy that the heavens were perfect, signifying the perfection of God. To admit that the Sun had spots or blemishes that moved and changed would be to challenge that perfection and the teachings of the Church. Galileo eventually made a breakthrough. Galileo noticed the shape of the sunspots became reduced as they approached the edge of the visible sun. -
Lectures 6, 7 and 8 October 8, 10 and 13 the Heliosphere
ESSESS 77 LecturesLectures 6,6, 77 andand 88 OctoberOctober 8,8, 1010 andand 1313 TheThe HeliosphereHeliosphere The Exploding Sun • We have seen that at times the Sun explosively sends plasma into the surrounding space. • This occurs most dramatically during CMEs. The History of the Solar Wind • 1878 Becquerel (won Noble prize for his discovery of radioactivity) suggests particles from the Sun were responsible for aurora • 1892 Fitzgerald (famous Irish Mathematician) suggests corpuscular radiation (from flares) is responsible for magnetic storms The Sun’s Atmosphere Extends far into Space 2008 Image 1919 Negative The Sun’s Atmosphere Extends Far into Space • The image of the solar corona in the last slide was taken with a natural occulting disk – the moon’s shadow. • The moon’s shadow subtends the surface of the Sun. • That the Sun had a atmosphere that extends far into space has been know for centuries- we are actually seeing sunlight scattered off of electrons. A Solar Wind not a Stationary Atmosphere • The Earth’s atmosphere is stationary. The Sun’s atmosphere is not stable but is blown out into space as the solar wind filling the solar system and then some. • The first direct measurements of the solar wind were in the 1960’s but it had already been suggested in the early 1900s. – To explain a correlation between auroras and sunspots Birkeland [1908] suggested continuous particle emission from these spots. – Others suggested that particles were emitted from the Sun only during flares and that otherwise space was empty [Chapman and Ferraro, 1931]. Discovery of the Solar Wind • That it is continuously expelled as a wind (the solar wind) was realized when Biermann [1951] noticed that comet tails pointed away from the Sun even when the comet was moving away from the Sun.