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Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Hans-Christian Helltegen

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LiU-ITN-TEK-A14/052 SE Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Hans-Christian Helltegen 2014-12-18 Department of Science and Technology Institutionen för teknik och naturvetenskap Linköping University Linköpings universitet nedewS ,gnipökrroN 47 106-ES 47 ,gnipökrroN nedewS 106 47 gnipökrroN LiU-ITN-TEK-A14/052 SE Visualizing Space Weather: Acquiring and Rendering Data of Earth's Magnetosphere Examensarbete utfört i Datateknik vid Tekniska högskolan vid Linköpings universitet Hans-Christian Helltegen Handledare Alexander Bock Examinator Anders Ynnerman Norrköping 2014-12-18 Upphovsrätt Detta dokument hålls tillgängligt på Internet – eller dess framtida ersättare – under en längre tid från publiceringsdatum under förutsättning att inga extra- ordinära omständigheter uppstår. Tillgång till dokumentet innebär tillstånd för var och en att läsa, ladda ner, skriva ut enstaka kopior för enskilt bruk och att använda det oförändrat för ickekommersiell forskning och för undervisning. Överföring av upphovsrätten vid en senare tidpunkt kan inte upphäva detta tillstånd. All annan användning av dokumentet kräver upphovsmannens medgivande. För att garantera äktheten, säkerheten och tillgängligheten finns det lösningar av teknisk och administrativ art. Upphovsmannens ideella rätt innefattar rätt att bli nämnd som upphovsman i den omfattning som god sed kräver vid användning av dokumentet på ovan beskrivna sätt samt skydd mot att dokumentet ändras eller presenteras i sådan form eller i sådant sammanhang som är kränkande för upphovsmannens litterära eller konstnärliga anseende eller egenart. För ytterligare information om Linköping University Electronic Press se förlagets hemsida http://www.ep.liu.se/ Copyright The publishers will keep this document online on the Internet - or its possible replacement - for a considerable time from the date of publication barring exceptional circumstances. The online availability of the document implies a permanent permission for anyone to read, to download, to print out single copies for your own use and to use it unchanged for any non-commercial research and educational purpose. Subsequent transfers of copyright cannot revoke this permission. All other uses of the document are conditional on the consent of the copyright owner. The publisher has taken technical and administrative measures to assure authenticity, security and accessibility. According to intellectual property law the author has the right to be mentioned when his/her work is accessed as described above and to be protected against infringement. For additional information about the Linköping University Electronic Press and its procedures for publication and for assurance of document integrity, please refer to its WWW home page: http://www.ep.liu.se/ © Hans-Christian Helltegen Visualizing Space Weather: Acquiring and Rendering Data of Earth’s Magnetosphere Master’s Thesis in Media Technology and Engineering HANS-CHRISTIAN HELLTEGEN Department of Science and Technology Media and Information Technology Linkoping¨ University Norrk¨oping, Sweden 2014 Abstract This thesis aims to describe the work and results of an intership at NASA’s Goddard Space Flight Center and part of the OpenSpace project. The project is a collabora- tion between Link¨oping University in Norrk¨oping, the American Museum of Natural History in New York and the Community Coordinated Modeling Center at NASA out- side Washington D.C. The work done during this intership has been to research and implement visualizations for Earth’s magnetosphere based on data from scientific space weather models. An interface was developed to access and read the data sets into the OpenSpace software, where the data is be rendered using volume ray-casting and field- line tracing. The fieldlines are a major part of this thesis and every step of the way from the seed points to the rendering are presented and discussed. All of these features and functionality have been implemented in the OpenSpace software which will continue to grow towards its goal of being able to interactively visualize space in a multi-screen environment in real time. Acknowledgements First off I would like to thank my supervisor Alexander Bock and my examinator pro- fessor Anders Ynnerman for entrusting me with this project, I really appreciate it and this have been a great experience! Also thank you Alex for your help with my thesis, your detailed feedback and notes have made the writing so much easier. Thank you Masha for doing everything in your power to help two lost Swedes find a place to live. Your generosity and kindness welcomed us in the best possible way to the US. Thanks to everyone at the CCMC for making me feel part of the gang and always being there to an- swer questions and give feedback. Without your expertise none of this would have been possible. Thank you Michael for putting up with my terrible jokes and trying to do the impossible task of education me about space. Bob, thank you for keeping us up-to-date with the general project and also making sure we’re heading the right direction. Thank you Jeimy for being an awesome roommate and giving me the latino experience. Thank you Aleksi and Andr´es for showing me D.C. and introducing me to so many fun people. You guys made my trip so much better and really helped me discover one of the best cities I’ve ever been in. Thanks Marina for confirming every single stereotype I had about Russians and taking me to all kinds of cool places. Thanks to all the other D.C. people who made my stay great! I am definitely returning one day and hope to see you all again. Jonas, thank you for being my partner in science. Having someone to exchange ideas and arrive in the US with was great. Finally thanks to my family and friends for all the encouragement, putting up with me being away and tolerating when I have been bad at keeping in touch. Hans-Christian, Link¨oping November 2014 Contents 1 Introduction 1 1.1 Context ..................................... 1 1.2 PurposeandRequirements .......................... 1 1.3 ThesisStructure ................................ 2 2 Background 3 2.1 OpenSpace ................................... 3 2.2 SpaceWeather ................................. 3 2.3 CCMC...................................... 5 2.4 Kameleon.................................... 5 2.5 BATS-R-US................................... 6 2.6 CDF....................................... 6 2.7 Fieldlines .................................... 7 2.8 Lorentz Force . 9 3 Method & Implementation 10 3.1 TheData .................................... 10 3.2 VolumeRendering ............................... 10 3.3 Kameleon Wrapper . 11 3.4 FieldlineTracing ................................ 12 3.5 Runge-Kutta .................................. 14 3.6 MagneticFields................................. 15 3.7 SeedPoints ................................... 15 3.8 GeometryLines................................. 16 3.9 Lorentz Force . 17 3.10 Billboards . 17 4 Results 19 4.1 VolumeRendering ............................... 19 4.2 FieldlineTracing ................................ 20 4.3 Fieldline Classification . 22 i CONTENTS 4.4 Billboards.................................... 23 4.5 Lorentz Force Trajectories . 26 5 Discussion 27 5.1 Kameleon Wrapper . 27 5.2 FieldlineTracing ................................ 28 5.3 Billboards.................................... 28 5.4 SeedPoints ................................... 29 5.5 Lorentz Force Trajectories . 29 6 Conclusion 30 Bibliography 31 ii 1 Introduction n this chapter I briefly outline some basic information for the thesis. I explain the I context behind the thesis, i.e. how it came to be, the purpose and requirements of the work, and finally the structure of the thesis. 1.1 Context This thesis is the result of an internship with the Community Coordinated Modeling Center (CCMC) at NASA’s Goddard Space Flight Center in USA for doing my master’s thesis as a part of the collaborative project OpenSpace. The thesis is written from a computer science perspective due to my background being engineering in media technol- ogy and computer science. The OpenSpace project began in 2012 and I am part of the third round of students sent. 1.2 Purpose and Requirements The purpose of this thesis and work is to implement visualization schemes for the mag- netosphere while developing the core OpenSpace software. These visualization needs to: • Run in real time. The visualizations are going to be used for exploration, so interactive speeds are a required. • Be scientifically correct. NASA researchers are going to use it for their research. • Be aesthetically pleasing. OpenSpace will be used for space shows at museums so the visual quality needs to be good. The resulting application also needs to be able to run cross-platform, i.e. on Linux, Mac, and Windows, in stereoscopic 3D and on multi-channel displays, such as planetariums. 1 1.3. THESIS STRUCTURE CHAPTER 1. INTRODUCTION 1.3 Thesis Structure In chapter 2, I explain the OpenSpace project, Space Weather, and the CCMC with their tools in depth. Then in chapter 3 of my thesis work, an overview of appropriate visualization techniques and the implementation of the selected visualization techniques are explained. In chapter 4 I showcase results from my implemented techniques and discuss how the work progressed. After that the results, techniques, and remarks are discussed in chapter 5. Finally in chapter 6 I give my thoughts on the work as a whole and give some closing words. 2 2 Background his chapter gives
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