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Exploring the Earth's Magnetic Field

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([SORULQJWKH(DUWK·V0DJQHWLF)LHOG $Q,0$*(6DWHOOLWH*XLGHWRWKH0DJQHWRVSKHUH An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 1 $FNQRZOHGJPHQWV Dr. James Burch IMAGE Principal Investigator Dr. William Taylor IMAGE Education and Public Outreach Raytheon ITS and NASA Goddard SFC Dr. Sten Odenwald IMAGE Education and Public Outreach Raytheon ITS and NASA Goddard SFC Ms. Annie DiMarco This resource was developed by Greenwood Elementary School the NASA Imager for Brookville, Maryland Magnetopause-to-Auroral Global Exploration (IMAGE) Ms. Susan Higley Cherry Hill Middle School Information about the IMAGE Elkton, Maryland Mission is available at: http://image.gsfc.nasa.gov Mr. Bill Pine http://pluto.space.swri.edu/IMAGE Chaffey High School Resources for teachers and Ontario, California students are available at: Mr. Tom Smith http://image.gsfc.nasa.gov/poetry Briggs-Chaney Middle School Silver Spring, Maryland Cover Artwork: Image of the Earth’s ring current observed by the IMAGE, HENA instrument. Some representative magnetic field lines are shown in white. An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 2 &RQWHQWV Chapter 1: What is a Magnet? , *UDGH 3OD\LQJ:LWK0DJQHWLVP ,, *UDGH ([SORULQJ0DJQHWLF)LHOGV ,,, *UDGH ([SORULQJWKH(DUWKDVD0DJQHW ,9 *UDGH (OHFWULFLW\DQG0DJQHWLVP Chapter 2: Investigating Earth’s Magnetism 9 *UDGH *UDGH7KH:DQGHULQJ0DJQHWLF3ROH 9, *UDGH 3ORWWLQJ3RLQWVLQ3RODU&RRUGLQDWHV 9,, *UDGH 0HDVXULQJ'LVWDQFHVRQWKH3RODU0DS 9,,, *UDGH :DQGHULQJ3ROHVLQWKH/DVW<HDUV ,; *UDGH 7KH0DJQHWRVSKHUHDQG8V ; *UDGH $6LPSOH0DJQHWRPHWHU ;, *UDGH $%LWRI*HRPHWU\ ;,, *UDGH :KDWLVDQ2VFLOODWLRQ3HULRG" ;,,, *UDGH :KDWLVDQ2VFLOODWLRQ$PSOLWXGH" ;,9 *UDGH 0DWKHPDWLFVRI6LPSOH2VFLOODWRUV ;9 *UDGH 7KH,QYHUVH&XEH/DZIRU0DJQHWLF)RUFHV Chapter 3: Magnetic Storms, Aurora and Space Weather ;9, *UDGH 0DJQHWLF6WRUPV)URPWKH*URXQG ;9,, *UDGH ,QYHVWLJDWLQJ0DJQHWLF6WRUPV ;9,,, *UDGH 0DJQHWLF6WRUPVDQG6RODU$FWLYLW\ ;,; *UDGH 0DJQHWLF6WRUPVDQG$XURUD ;; *UDGH 5RXQGWKH&ORFN0RQLWRULQJRI$XURUD ;;, *UDGH 7KH(YROXWLRQRIDQ$XURUDLQ7LPH ;;,, *UDGH 7KH$XURUDO%DWWHU\DQG(OHFWULFDO&LUFXLW ;;,,, *UDGH 7KH0DJQHWRSDXVH%RXQGDU\'LVWDQFH An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 3 &RRUGLQDWLRQZLWK6FLHQFH6WDQGDUGV 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Inquiry X XXXX XXXXXXXXXX Motion X XXX XX X Forces XXXX XXXXXX XXXXXXX Light X Electricity X X Magnetism XXXXXXXXXXXXX XXXXXXXX Energy X X XXXXXX Astronomy XX XXXXXXXXX XXXXXXXXX Earth XX XXXXX XXXX XXXXXXXXX Technology X XXXX XXXX XXXXXXXX XXXX Science XXXX Human Endeavor What is a Investigating the Earth’s Magnetism Magnetic Storms, Aurora and Magnet? Space Weather This book was designed to provide teachers with activities that allow students to explore topics related to the Sun-Earth Connection. We have provided a full range of activities for the grades 3-12 community so that teachers may see how the single topic of magnetism can evolve in sophistication as the student matures. Teachers are invited to use the activities as-is, or to modify them as needed to suit their particular objectives. The units are designed for use in conjunction with your current curriculum as individual lessons or as a unit. The chart above is designed to assist teachers in integrating the activities contained with existing curricula and National Science Standards. Throughout the lessons you will find activities that require the students to make observations, and record their findings. Observations can be recorded in science learning logs, journals or by organization into charts or graphs. An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 4 ,QWURGXFWLRQ "Students should be actively engaged in learning to view the world scientifically. They should be encouraged to ask questions about nature and to seek answer, collect things, count and measure things, make qualitative observations, organize collections and observations and discuss findings." (American Association for the Advancement of Science; Benchmarks for Science) Scientists and students share an active curiosity about the world. A true scientist maintains that inquisitive quality and continues to question, explore and investigate. In developing this book, we have attempted to stimulate an active curiosity about the Sun-Earth Connection, and specifically how Earth and its magnetic field react to solar influences. The activities in this book combine hands-on experimentation with the use of satellite data resources on the internet, to provide students with a well-rounded perspective into basic issues in contemporary Sun- Earth research. "When students observe differences in the way things behave or get different results in repeated investigations, they should suspect that something differs from trial to trial, and try to find out what." (AAAS ‘Benchmarks for Science Literacy, 1999) Each lesson focuses upon a particular aspect of studying the Sun and the Earth as a system, and how scientists make the observations. Included in the procedure sections are questions that will further encourage scientific inquiry. Each lesson begins with a description of the activities in which the students will participate, and provides general background information. The objectives sections highlight the science process skills the students will develop while completing the activities. The procedures sections are general, and can be adapted to meet the knowledge and developmental levels of the students. Many lessons have extension activities designed to have the students apply the new knowledge in grade appropriate activities. Although the lessons may be used with only the information provided, we include where appropriate the addresses of web pages on the Internet, and on the IMAGE ‘Space Weather’ CDROM, so that further material can be incorporated into the lesson. For further information, please visit the IMAGE satellite’s Education and Public Outreach web site at: An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 5 7KHVFLHQWLILFVWXG\RI(DUWK·VPDJQHWLFILHOGLVDFRPSOH[VXEMHFWWKDWKDVHYROYHG WUHPHQGRXVO\VLQFH:LOOLDP*LOEHUW·VERRN¶'H0DJQHWH·ZDVSXEOLVKHGLQ7KH ·V ZHUH D SHULRG RI XQGHUVWDQGLQJ KRZ PDJQHWLF IRUFHV RSHUDWHG LQ JUHDW PDWKHPDWLFDOGHWDLOE\SK\VLFLVWVVXFKDV2HUVWHG)DUDGD\DQG*DXVVFXOPLQDWLQJ ZLWKWKHHOHFWURPDJQHWLFWKHRU\E\-DPHV&OHUN0D[ZHOO7KHUHODWLRQVKLS RI ODERUDWRU\PDJQHWVWRWHUUHVWULDOPDJQHWLVPEHFDPHDG\QDPLFVFLHQWLILFGLVFLSOLQH RQFHSK\VLFLVWVUHDOL]HGWKDWDXURUDZHUHUHODWHGWRGLVWXUEHGPDJQHWLFFRQGLWLRQV DGLVFRYHU\PDGHE\$OH[DQGHUYRQ+XPEROWLQWKH·V'XULQJWKHWKFHQWXU\ VRSKLVWLFDWHGSK\VLFVPRGHOVZHUHGHYHORSHGWRH[SODLQKRZ(DUWK·VPDJQHWLFILHOG FKDQJHVHVSHFLDOO\GXHWRVRODUVWRUPVDQGWKHRXWSRXULQJRIPDWWHU DQG HOHFWURPDJQHWLFHQHUJ\ 6DWHOOLWHREVHUYDWLRQVVLQFHWKH·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·VPDJQHWLFILHOGDQGZK\VSDFHZHDWKHULVVXHV DUHEHFRPLQJLQFUHDVLQJO\LPSRUWDQWYLVLWWKHIROORZLQJZHEUHVRXUFHV ,0$*((GXFDWLRQ:HESDJH KWWSLPDJHJVIFQDVDJRYSRHWU\ ([SORUDWLRQRIWKH0DJQHWRVSKHUH KWWSZZZLVWSJVIFQDVDJRY(GXFDWLRQ,QWURKWPO 1$6$6XQ(DUWK)RUXP KWWSVXQHDUWKJVIFQDVDJRY 1$6$2665HVRXUFH'LUHFWRU\ KWWSWHDFKVSDFHVFLHQFHVWVFLHGX 6SDFH:HDWKHU,OOXVWUDWHG3ULPHU KWWSVXQHDUWKJVIFQDVDJRYVHFKWPOWXWKWPO 7RGD\·V6SDFH:HDWKHU KWWSZZZVHFQRDDJRY6:1 $UHFHQWERRNDERXWKXPDQLPSDFWV KWWSZZZWKHDVWURQRP\FDIHQHW An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 6 $OWKRXJKLWLVQRWUHTXLUHGLQRUGHUWRXVHWKLVWHDFKHU·VJXLGHWKH,0$*(¶6SDFH :HDWKHU· &'520 KDV PDQ\ UHVRXUFHV WKDW DUH UHOHYDQW WR WKH DFWLYLWLHV LQ WKLV ZRUNERRN+HUHLVDVKRUWLQGH[RIWKHUHVRXUFHVDVVXPLQJWKDW\RXU FRPSXWHU OLVWHGWKH&'520GHYLFHDV¶'ULYH,· 6XSSOHPHQWDU\DFWLYLW\ZRUNERRNVIRU.VWXGHQWV ILOH,_SRHWU\DFWLYLWLHVKWPO $UWLFOHVDERXWWKH,0$*(PLVVLRQVSDFHZHDWKHUDQGKXPDQLPSDFWV ILOH,_SRHWU\UHVRXUFHVKWPO &DVHKLVWRULHVRIVHYHUDOPDMRUVWRUPVLQFOXGLQJUHSUHVHQWDWLYHGDWD ILOH,_SRHWU\WRGD\,0$*(6((KWPO ,PDJHVDQGPRYLHVIURPWKH,0$*(VDWHOOLWH ILOH,_SRHWU\PXOWLPHGLDKWPO +RZWREXLOGDPDJQHWRPHWHUDQGMRLQ¶0DJ1HW· ILOH,_SRHWU\ZRUNERRNPDJQHWKWPO )$4VDERXWDVWURQRP\DQGVSDFHSK\VLFV ILOH,_SRHWU\DVNDVNPDJKWPO 7KHODWHVWQHZVIURP,0$*( ILOH,_SRHWU\QHZVQHZQHZVKWPO 6SDFH:HDWKHU3ULPHU ILOH,_SRHWU\WXWRULDOWXWKWPO /LYHGDWDIURPVSDFH ILOH,_SRHWU\WRGD\LQWURKWPO :KDWLV6SDFH:HDWKHU" ILOH,_SRHWU\VN\WHOKWP ,QWURGXFLQJWKH,0$*(VDWHOOLWH ILOH,_SRHWU\VZULLQGH[KWPO An IMAGE Satellite Guide to Exploring the Earth’s Magnetic Field 7 ,3OD\LQJZLWK0DJQHWLVP ,QWURGXFWLRQ 2EMHFWLYHV What is magnetism? We have all had the • Students will identify items that are experience of using simple magnets to hold attracted to magnets. notes on surfaces such as refrigerator doors. Magnetism is the force produced by • Sudents will experiment with an magnets which does all of the "holding". invisible force. Magnetism is also a very important force in nature which can move hot gases in stars, • Students will learn about polarity. and in the space around Earth. The students will investigate magnetism and magnetic
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  • Permanent Magnet Design Guidelines

    Permanent Magnet Design Guidelines

    NOTE(2019): THIS ORGANIZATION (MMPA) IS OBSOLETE! MAGNET GUIDELINES Basic physics of magnet materials II. Design relationships, figures merit and optimizing techniques Ill. Measuring IV. Magnetizing Stabilizing and handling VI. Specifications, standards and communications VII. Bibliography INTRODUCTION This guide is a supplement to our MMPA Standard No. 0100. It relates the information in the Standard to permanent magnet circuit problems. The guide is a bridge between unit property data and a permanent magnet component having a specific size and geometry in order to establish a magnetic field in a given magnetic circuit environment. The MMPA 0100 defines magnetic, thermal, physical and mechanical properties. The properties given are descriptive in nature and not intended as a basis of acceptance or rejection. Magnetic measure- ments are difficult to make and less accurate than corresponding electrical mea- surements. A considerable amount of detailed information must be exchanged between producer and user if magnetic quantities are to be compared at two locations. MMPA member companies feel that this publication will be helpful in allowing both user and producer to arrive at a realistic and meaningful specifica- tion framework. Acknowledgment The Magnetic Materials Producers Association acknowledges the out- standing contribution of Parker to this and designers and manufacturers of products usingpermanent magnet materials. Parker the Technical Consultant to MMPA compiled and wrote this document. We also wish to thank the Standards and Engineering Com- mittee of MMPA which reviewed and edited this document. December 1987 3M July 1988 5M August 1996 December 1998 1 M CONTENTS The guide is divided into the following sections: Glossary of terms and conversion A very important starting point since the whole basis of communication in the magnetic material industry involves measurement of defined unit properties.