How to Oberve the Sun Safely 2nd by Macdonald

free ebooks ==> www.ebook777.com www.ebook777.com free ebooks ==> www.ebook777.com Patrick Moore’s Practical Astronomy Series For further volumes: http://www.springer.com/series/3192 free ebooks ==> www.ebook777.com www.ebook777.com free ebooks ==> www.ebook777.com How to Observe the Sun Safely Second Edition Lee Macdonald free ebooks ==> www.ebook777.com Lee Macdonald Cambridge,UK ISSN 1431-9756 ISBN 978-1-4614-3824-3 ISBN 978-1-4614-3825-0 (eBook) DOI 10.1007/978-1-4614-3825-0 Springer New York Heidelberg Dordrecht London Library of Congress Control Number: 2012937044 © Springer Science+Business Media New York 2012 This work is subject to copyright All rights are reserved by the Publisher, 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 any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer Permissions for use may be obtained through RightsLink at the Copyright Clearance Center Violations are liable to prosecution under the respective Copyright Law The use of general descriptive names, registered names, trademarks, service marks, etc in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made The publisher makes no warranty, express or implied, with respect to the material contained herein Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) www.ebook777.com free ebooks ==> www.ebook777.com Preface There is now more interest in observing the Sun than ever before among amateur astronomers Go to any major astronomical meeting or convention and you will see at least one solar telescope in action, and it is sure to draw a crowd The Sun indeed has much to offer the amateur astronomer with modest equipment On most days, it shows sunspots and other features that display a wealth of fine detail and change their appearance strikingly from day to day But observing the Sun can be dangerous Never look at the sun through an ordinary telescope or other optical aid, even for a brief instant The Sun’s intense radiation, amplified and focused by a telescope, will almost certainly cause eye injury and could well lead to complete blindness Do not attempt any solar observing until you have read and understood the safety precautions and observing advice set out in Chap of this book – even if you think you have the correct equipment Be especially wary about using filters to observe the Sun If you have a filter that makes the Sun look dark, it is not necessarily safe, as it is largely the Sun’s invisible radiation that is harmful to the eye However, provided you use the correct techniques, such as projecting the solar image onto a screen or using a specially designed high-quality solar filter that fits over the telescope aperture, it is quite easy to observe the Sun safely One of the joys of solar observing is that useful observations are possible even with very small telescopes – such as the small refractors, Schmidt–Cassegrains, and Maksutov telescopes − that are readily available off the shelf In fact, due in part to the fact that the Sun has more than enough light, a small telescope can actually give better results than a large one! Observing the Sun is also not affected by light pollution, a major advantage for the many amateur astronomers whose view of the night sky is obscured by the glow of streetlights and security lighting The Sun can be observed from a busy town just as successfully as from the remote countryside v free ebooks ==> www.ebook777.com vi Preface Our nearest star is studied intensively by professional astronomers and is monitored around the clock, using space-based observatories as well as telescopes from the ground, and both the level of research and the equipment required to carry it out are far beyond the amateur’s means Therefore, solar observing does not offer the potential for discoveries or making major scientific contributions, like some other branches of amateur astronomy, such as supernova hunting or variable star observing But monitoring solar features and keeping careful records of them is still important Throughout the world, many amateur astronomers systematically monitor the Sun and send their observations to solar observing organizations for analysis Monitoring levels of sunspot activity is particularly useful, as it continues a long series of observations made with small telescopes since the nineteenth century, which provide by far the best long-term record of solar activity that we have and is vital to our understanding of the Sun’s behavior and any effects it might have on Earth’s climate More observers are always welcome in these sunspot counting programs Solar photography is also useful, as it has considerable educational value Professional solar images tend only to show small parts of the Sun or show our nearest star at invisible wavelengths, where its appearance is radically different from that in visible light Amateur images, on the other hand, portray the Sun more realistically and so are more meaningful to the wider public Indeed, as well as amateur astronomers, this book is also intended for those bringing astronomy to a wider audience, such as professional scientists engaged in public outreach activities, which are increasingly important in the present age of budget cutbacks, when scientists are under increasing pressure to bring their subject to the public and justify its value to the taxpayer The first edition of How to Observe the Sun Safely (Springer, 2003), was mostly written during 2001 But since that time, solar observing – and amateur astronomy as a whole – has undergone radical changes The most fundamental of these has been the digital revolution and the almost complete substitution of digital imaging for film photography The first edition had a chapter on digital photography, but the book’s main emphasis was on 35-mm work Digital cameras were still in their infancy: their resolution and exposure capabilities were modest, and they were difficult to use with telescopes Digital SLRs did exist, but they cost over $2,000, putting them out of the reach of most amateurs And no one had thought of using a webcam, costing (and weighing) less than an eyepiece to take high-resolution images All this has now changed Digital SLRs now start at under $500 and take better images than their 35-mm predecessors, with all the benefits of digital imaging − the ability to see and evaluate your results on the spot, and no more waiting to finish a roll of film and have it developed At the same time, amateurs are routinely using webcams to take images of sunspots and H-alpha solar features with a resolution once reserved for professional observatories Another revolution has taken place in the affordability, and availability, of telescopes and filters for observing the Sun in H-alpha In 2001, the revolution was beginning, with the appearance of the Coronado SolarMax 40, the first “sub-angstrom” H-alpha filter to be available for under $1,000 And, since then, the www.ebook777.com free ebooks ==> www.ebook777.com Preface vii revolution has continued Now, some solar telescopes costing as little as $500 can show spectacular solar features that before 2001 would have required instruments costing five to ten times as much Two other companies – Lunt and Solarscope – have appeared and are producing high-quality H-alpha filters and telescopes, as has a revived DayStar (long the only source of sub-angstrom H-alpha filters for amateurs), with the result that the amateur now has a vast and potentially confusing array of equipment to choose from Therefore, there is all the more need for an up-to-date guide to show the amateur what to look for on the Sun, how to record observations, and what equipment to use This second edition is aimed at the amateur who knows the basics of astronomy and wants to know how to go about observing the Sun What is emphasized is what is possible using commercially available equipment that is easy to get hold of in most parts of the world For this reason, I have deliberately eschewed some specialized topics, such as observing the Sun’s radio emissions, which requires homemade equipment and a fair amount of technical know-how Neither I discuss in much detail the Sun-related topics of eclipses and the aurora Both are major fields in astronomy by themselves, and some good books on them have already been published Throughout the book, the emphasis is on practical solar observing – what you can with ordinary equipment, provided you take the proper safety precautions I have tried to avoid unnecessary theory and have not attempted detailed scientific explanations, as these are available elsewhere Rather, this book is intended as a basic guide to give the amateur a taste for observing our ever-changing nearest star, in the hope that he or she will explore further free ebooks ==> www.ebook777.com www.ebook777.com free ebooks ==> www.ebook777.com Acknowledgments I would like to thank Dave Tyler for permission to use his exceptionally detailed images – surely among the best solar images ever taken by an amateur astronomer – and Derek Hatch for his fine solar eclipse pictures Thanks are also due to Richard Bailey (Solar Section Director of the Society for Popular Astronomy) for supplying photographs of his H-alpha filter I owe a particular debt of gratitude to Dr Dominic Ford of the Cavendish Laboratory, Cambridge University, UK for his time in preparing the exquisite line diagrams from my freehand sketches, using the PyXPlot software that he wrote himself Another Cambridge colleague, Mark Hurn, kindly provided access to library facilities and enabled me to photograph some equipment at the Institute of Astronomy at Cambridge Peter Meadows generously gave me permission to reproduce one of his Stonyhurst solar disks, and Lyn Smith, Solar Section Director of the British Astronomical Association, allowed me to use BAA Solar Section data to plot a graph of solar activity from 2001 to 2010 I am grateful to David Hathaway (NASA Marshall Space Flight Center) for permission to use the diagram in Fig 4.8 Last, but by no means least, I must thank John Watson, my editor at Springer for the first edition of How to Observe the Sun Safely, for starting off the process that has led to this new edition and Maury Solomon, Springer’s current Editor for Astronomy and Physics, for seeing this new book through the press Cambridge, UK June 2012 Lee Macdonald ix free ebooks ==> www.ebook777.com Appendix A 199 refractor of focal length 910 mm projecting using a 15 mm Plưssl eyepiece (magnification 61×), the distances were: Average 263 mm Maximum 270 mm Minimum 258 mm You need to build your box so that it allows for the maximum projection distance required If the box is a little too long you can shorten the distance slightly, and thus get the image down to the correct size by pulling the eyepiece out a little in its drawtube, but if it is too short you cannot extend the box! The final length for your projection box is this distance (marked d in Fig A.1) plus the distance by which the Pipe Bracket Star Diagonal (seen from behind) Eyepiece 6.4 mm– thick Balsa Wood d Projection Screen CornerJoint Fig A.1 Diagram showing the construction of the author’s projection box The projection distance d determines the diameter of the projected solar image www.ebook777.com free ebooks ==> www.ebook777.com 200 Appendix A eyepiece protrudes into the box When you use the box, you can make small changes to the projection distance to allow for the variation in the Sun’s apparent size by adjusting the position of the eyepiece in its drawtube Inserting the eyepiece fully will give the maximum projection distance, whereas pulling it out by a few millimeters and then clamping it again will give the minimum The screen end of the box can be square When determining its size, allow for mm of clearance around the solar disc (i.e., mm on each side if measuring its cross section), plus the thickness of the square corner joints holding the box together (another 26 mm or in in total) and the thickness of the sides of the box (total 13 mm or ½ in.) For the box in the example, then, the total width of the base comes to: 152 mm + mm + mm + 26 mm + 13 mm = 201 mm Thus the screen end of the box should be 201 mm square The top piece, through the center of which the eyepiece mount should be inserted, has the same width as the tops of the side pieces (75 mm, in.) and the same length as the internal width of the box (188 mm) The hole for the eyepiece or drawtube (see below) should be just wide enough for the tube to slide through with as little play as possible If you have access to a lathe or other precision cutting device, boring a hole of the correct diameter should not be a problem If you only have access to hand tools, you can make a very functional eyepiece hole quite easily by drawing a circle of the correct diameter in the exact center of the top piece and then drilling a series of small holes around its circumference If the holes are spaced reasonably closely together, you can then break down the walls between them with a chisel until the central piece of wood falls out You can file the interior of the resulting hole smooth with sandpaper—though be careful not to make it too big for the tube The front of the box—i.e., the side not used for looking at the Sun’s image—needs to be blocked in, preferably with more balsa wood for rigidity, or with thick black card You now have a box with just one open side, into which you look to view the Sun’s projected image How you attach the box to the telescope depends on the characteristics of your instrument Ideally, the box should slide over the drawtube and be clamped either with a screw attached to a collar at the front of the box, or by making the box fit very tightly over the drawtube (e.g., by lining the eyepiece hole with felt) However, some telescopes, particularly small refractors, may not reach focus without a star diagonal In this case, you need to slide the box over the eyepiece end of the star diagonal, so that the box’s long dimension is at right angles to the telescope tube Clamping the box rigidly to the telescope tube requires some ingenuity if you use a star diagonal I attached a pipe bracket (obtained from the plumbing section of a hardware store) to the top piece of the box, with a bolt passing through it and so clamping the box tightly to the eyepiece collar of the main telescope Two smaller bolts going through the sides of the pipe bracket keep the box’s orientation steady (Figs A.1 and A.2) free ebooks ==> www.ebook777.com Appendix A 201 Fig A.2 The author’s projection box, attached to an 80 mm (3.1 in.) refractor with a pipe bracket Using the star diagonal method of projecting the Sun’s image is probably better than direct projection, as you can better shade the interior of the box from ambient sunlight, and the near-horizontal position of the Sun’s image makes it easier to view A disadvantage is that it projects a reversed solar image—i.e., east left, west right, which is the opposite way around from a solar image projected straight through Orientation of the Sun’s image is discussed in more detail in Chap To obtain the best projected images you should use a good quality, thick paper Many amateurs over the years have used “Bristol board,” a very smooth white paper available from art shops This gives very good results, but the thick, smooth cartridge paper with a slightly creamy tint shows sunspot detail even better Faculae, though, are more prominent on Bristol board You can use a sheet of Bristol board and a sheet of cartridge paper pasted together, so that you can flip between the two surfaces to see the two types of solar features to their best advantage To plot sunspot positions use a rotatable projection grid made of Bristol board; again, this is discussed in detail in Chap www.ebook777.com free ebooks ==> www.ebook777.com Appendix B Equipment Suppliers This list is not intended to be comprehensive but rather is a selection of suppliers of solar observing equipment that amateur astronomers have found to be useful It does not constitute a recommendation of these suppliers and neither the author nor the publisher makes any guarantee as to the safety of these products or their suitability for solar observing Try to solicit the advice of an experienced solar observer before buying any piece of equipment Suppliers of astronomical equipment exist in vast numbers This list is restricted, therefore, to those companies selling products either specifically for solar observing or useful for solar work To find suppliers of telescopes and other general astronomical equipment, try your favorite Internet search engine or peruse the advertisements in astronomy magazines (see Appendix D, “Further Reading”) Suppliers in North America Astro-Physics, Inc., www.astro-physics.com Suppliers in USA of Baader Planetarium filters and accessories Celestron International, www.celestron.com Solar filters and accessories to suit the wide range of Celestron telescopes; also the NexImage camera, a webcam optimised for astronomy Celestron not sell directly to the public, but their products can be obtained through Celestron dealers worldwide Contact Celestron to find your nearest dealer Coronado, part of Meade Instruments, www.meade.com/product_pages/coronado/coronado.php A leading manufacturer of sub-angstrom H-alpha filters and L Macdonald, How to Observe the Sun Safely, Patrick Moore’s Practical Astronomy Series, 203 DOI 10.1007/978-1-4614-3825-0, © Springer Science+Business Media New York 2012 free ebooks ==> www.ebook777.com 204 Appendix B solar telescopes for the amateur solar observer, including the Personal Solar Telescope (PST), a complete H-alpha solar telescope for just under $500 DayStar Filters LLC, www.daystarfilters.com The longest-running manufacturers of sub-angstrom H-alpha filters Kendrick Astro Instruments, www.kendrickastro.com/astro/solarfilters.html Suppliers of Baader AstroSolar filters Lumenera Corporation, www.lumenera.com Top-of-the-line webcam-type cameras suitable for high-resolution solar imaging Orion Telescopes & Binoculars, www.telescope.com Suppliers of full-aperture glass solar filters for white-light observing and Coronado H-alpha telescopes; also many useful accessories, including adapters for mounting digital cameras to telescopes Point Grey Research, www.ptgrey.com/products/flea3/flea3_firewire_camera asp Suppliers of the tiny, but highly effective, Flea3 webcam-type camera suitable for high-resolution solar imaging Thousand Oaks Optical, www.thousandoaksoptical.com Manufacturers of both glass and plastic white-light solar filters for visual observing, solar eclipse viewers, glass filters for solar photography and 1.5-Å H-alpha prominence filters Suppliers in the UK and Europe Telescope House (Broadhurst Clarkson and Fuller Ltd), www.telescopehouse.com Suppliers of white-light solar filters and Coronado H-alpha filters and telescopes Baader Planetarium, www.baader-planetarium.com Manufacturers of Baader AstroSolar Safety Film and AstroSolar Photo Film Mylar-type aperture filters, also many other filters and accessories for solar observing—e.g the “Fringe-Killer” filter David Hinds Ltd, www.dhinds.co.uk UK suppliers of Baader Planetarium equipment; also of telescopes and accessories by Celestron See the two separate websites: www.celestron.uk.com and www.baader-planetarium.uk.com The Imaging Source, www.theimagingsource.com/en_US Manufacturers of advanced webcam-type cameras for high-resolution imaging Lunt Solar Systems, www.lunt-solarsystems.eu Manufacturers of a wide range of H-alpha and Ca-K solar telescopes and filter systems SCS Astro, www.scsastro.co.uk Solar filters, including DayStar filters Solarscope, www.solarscope.co.uk Manufacturers of high-end H-alpha solar filters and telescopes The Widescreen Centre, www.widescreen-centre.co.uk UK suppliers of Lunt solar filters and telescopes www.ebook777.com free ebooks ==> www.ebook777.com Appendix C Solar Observing Organizations Astronomy Clubs If you are new to solar observing, and certainly if you are starting out in astronomy, the first place you should go for advice on observing is your nearest local astronomy club or society There are bound to be some members there with experience of solar observing and most are willing to provide help and encouragement as well as advice on what equipment to buy If you cannot find a local society in your area, try contacting the following national organizations of astronomy clubs: (In the USA): The Astronomical League, www.astroleague.org/, maintains a list of local astronomy clubs and their contact details The monthly magazine Sky & Telescope (see also under “Magazines” in Appendix D) has a web page that allows you to search for astronomy clubs (and also museums, observatories and planetariums) in your area: http://www.skyandtelescope.com/community/organizations (In the UK): The Federation of Astronomical Societies (FAS), http://www fedastro.org.uk/fas/, maintains a list of local societies that are members of the FAS, including their websites and details of their meetings National Organizations in the United States The Solar Section of the American Association of Variable Star Observers, www.aavso.org/solar, focuses on determining the American Relative Sunspot Number (RA) using sunspot counts supplied by contributing members L Macdonald, How to Observe the Sun Safely, Patrick Moore’s Practical Astronomy Series, 205 DOI 10.1007/978-1-4614-3825-0, © Springer Science+Business Media New York 2012 free ebooks ==> www.ebook777.com 206 Appendix C The Association of Lunar and Planetary Observers, http://alpo-astronomy org/, also has a Solar Section which emphasizes recording solar activity pictorially—by drawings and electronic imaging Royal Astronomical Society of Canada, www.rasc.ca Publishes the very useful annual Observer’s Handbook National Organizations in the UK The leading association of amateur astronomers in Great Britain is the British Astronomical Association, www.britastro.org The BAA has a very active Solar Section, to which several dozen members send monthly observations You can access its website through the BAA home page above If you are new to solar observing you may wish to consider joining the Society for Popular Astronomy, www.popastro.com The SPA is a national society for beginning and intermediate amateur astronomers of all ages It has a very active Solar Section that helps beginners master the basic techniques of solar observing The SPA also publishes a lively bimonthly magazine, Popular Astronomy; in this, the Solar Section publishes regular reports based on observations sent in by members www.ebook777.com free ebooks ==> www.ebook777.com Appendix D Further Reading Books on the Sun and Solar Observing BECK, R et al., Solar Astronomy Handbook (Willmann-Bell, 1995) A very detailed compendium of amateur methods of observing and imaging the Sun, covering a number of technical topics not described in this book, including observing the Sun at radio wavelengths Rather dated now, but a good reference for the more advanced solar observer GOLUB, L and PASACHOFF, J M., Nearest Star: the surprising science of our sun (Harvard University Press, 2001) An easy-to-read guide to how the Sun works JENKINS, J L., The Sun and How to Observe It (Springer-Verlag, 2009) A technical guide to observing and imaging the Sun LANG, K R., Sun, Earth and Sky (2nd edition, Springer-Verlag, 2006) A guide to our current knowledge of the Sun and its influence on Earth LANG, K R., The Cambridge Encyclopaedia of the Sun (Cambridge University Press, 2001) A beautifully-illustrated guide to our nearest star It describes the workings of the Sun to a quite high technical level, although mathematics are presented separately in text boxes and so not interrupt the flow of the narrative MOBBERLEY, M., Lunar and Planetary Webcam User’s Guide (SpringerVerlag, 2006) An introduction to webcam imaging; includes a chapter on imaging the Sun with a webcam PHILLIPS, K J H., Guide to the Sun (Cambridge University Press, 1992) An accessible but detailed guide to the Sun and how it works L Macdonald, How to Observe the Sun Safely, Patrick Moore’s Practical Astronomy Series, 207 DOI 10.1007/978-1-4614-3825-0, © Springer Science+Business Media New York 2012 free ebooks ==> www.ebook777.com 208 Appendix D PUGH, P., Observing the Sun with CoronadoTM Telescopes (Springer-Verlag, 2007) A survey of the various solar telescopes, filters and accessories that were available at the time of the book’s publication TAYLOR, P O., Observing the Sun (Cambridge University Press, 1991) A detailed guide to monitoring solar activity by sunspot counting and electronic methods Books on Photography and Digital Imaging BERRY, R., and BURNELL, J., The Handbook of Astronomical Image Processing, 2nd Edition (Willmann-Bell, Inc., 2004) A detailed guide to image processing, with a companion CD-ROM containing AIP4WIN image processing software COVINGTON, M A., Astrophotography for the Amateur (2nd Edition, Cambridge University Press, 1999) A detailed guide to all aspects of amateur astrophotography COVINGTON, M A., Digital SLR Astrophotography (Cambridge University Press, 2007) A specialised guide to astrophotography techniques with DSLR cameras Contains some very brief notes on webcam imaging DRAGESCO, J., High Resolution Astrophotography (translated by Richard McKim, Cambridge University Press, 1995) A “classic” from the 35 mm film era, this book is nevertheless essential reading for the serious solar observer and imager today, for it includes thorough technical discussions on resolution, seeing conditions, observing sites, telescopes and accessories—all as important in the digital age as they were in the age of film IRELAND, R S., Photoshop Astronomy (2nd edition, Willmann-Bell, Inc.) A detailed guide to astronomical image processing using Adobe Photoshop Comes with a companion DVD REEVES, R., Introduction to Digital Astrophotography: Imaging the Universe with a Digital Camera (Willmann-Bell, Inc., 2005) A superb guide to imaging with digital cameras It covers compact digital cameras as well as DSLRs and has a strong chapter on webcam imaging REEVES, R., Introduction to Webcam Astrophotography: Imaging the Universe with the amazing, affordable webcam (Willmann-Bell, Inc.) A book devoted to webcam imaging, by the author of Introduction to Digital Astrophotography (above) Reference Books The Handbook of the British Astronomical Association is published annually by the British Astronomical Association (Burlington House, Piccadilly, London) It contains detailed solar data, including P, B0 and L0 (essential for working out solar co-ordinates) tabulated at 5-day intervals See Appendix B for more about the British Astronomical Association www.ebook777.com free ebooks ==> www.ebook777.com Appendix D 209 The Astronomical Almanac is also published annually and is a collaboration between Her Majesty’s Stationery Office in the UK and the United States Naval Observatory It is available in both countries from astronomy book suppliers The Almanac tabulates P, B0 and L0 at daily intervals Willmann-Bell, Inc also publishes a software version of the Almanac known as the Multiyear Interactive Computer Almanac 1800–2050 Magazines The major commercial astronomy magazines often contain articles on solar observing and the latest developments in our understanding of the Sun If you are a serious solar observer (or a serious amateur astronomer of any kind), it is a good idea to get at least one magazine regularly, as they often present information that is more upto-date than in books Sky and Telescope (www.skyandtelescope.com/) contains many “how to” observing articles Astronomy (www.astronomy.com/) also has many articles on practical astronomy Both magazines can often be found in British newsagents as well In the United Kingdom, Astronomy Now (www.astronomynow.com/) and Sky At Night (www.skyatnightmagazine.com/), published by the BBC, are both available from many British newsagents Both are very strong on equipment reviews Websites The following websites may be of use to the solar observer: Current Solar Images From Earth Big Bear Solar Observatory: http://www.bbso.njit.edu/ Mount Wilson Observatory: http://www.mtwilson.edu/sci.php Uccle Solar Equatorial Table (images from Europe): http://sidc.oma.be/uset/ index.php Current Solar Images From Space SOHO spacecraft: http://sohowww.nascom.nasa.gov/ Solar Dynamics Observatory: http://sdo.gsfc.nasa.gov/ STEREO spacecraft: http://stereo.gsfc.nasa.gov/ Solar Activity, Space Weather and Aurora Warnings Current solar activity and space weather: http://spaceweather.com/ (also includes other astronomical images sent in by viewers) Space Weather Prediction Center: http://www.swpc.noaa.gov/ Current solar active regions with official AR numbers: http://www.nwra.com/ spawx/listsrs.html free ebooks ==> www.ebook777.com 210 Appendix D Solar Position Measurements Peter Meadows’s website (UK)—Stonyhurst discs and software for determining heliographic coordinates: www.petermeadows.com TiltingSun—software for determining P, B0 and L0 and showing the Sun’s current tilt and orientation: http://www.atoptics.co.uk/tiltsun.htm Current values of P, B0 and L0: http://www.jgiesen.de/sunrot/index.html Sunspot Numbers Solar Influences Data Analysis Center (SIDC)—http://sidc.oma.be/ Publishes the official Relative Sunspot Number, in continuation of the Relative Sunspot Number begun by Rudolf Wolf in 1848 American Association of Variable Star Observers (AAVSO)—Solar Section— http://www.aavso.org/solar Issues a monthly electronic Solar Bulletin that publishes the American Sunspot Number—RA www.ebook777.com free ebooks ==> www.ebook777.com Index A Active areas, 84–88, 90, 91, 93, 94, 103, 128 Active prominences, 125–127 Active regions, 9–11, 55, 59, 79, 105, 115, 118, 125–127, 130, 131, 182 Adapters (for cameras), 143, 150, 154, 168 Adobe Photoshop, 187, 193, 194, 196 Adobe Photoshop Elements, 187–189, 193–196 Afocal method (photography), 151, 164, 168, 169, 190 Alt-azimuth mountings, 25, 26, 69, 135 Aperture filters, 24, 25, 32, 33, 35–37, 45, 98, 146, 152, 156, 163, 168, 180 Aurorae, 13, 14, 55, 61 Autofocus, 163, 166 Automatic exposure, 141, 162 B B0, 73–76, 90, 97, 98 Baader coronagraph, 119–121 Baader filters (white-light), 34, 125 Baader K-line filter, 125 Binoculars, 37–39 Bipolar sunspot group, 51, 53, 75 Brightness (in image processing), 88, 89, 191–194, 196 Butterfly diagram, 78, 79 C Cable release, 144, 155, 157, 164 Ca-K See Calcium-K Calcium-K, 62, 102, 124–125 Camera adapters, 148, 150, 154, 157, 158, 168 Cameras CCD, 63, 123, 137, 138, 145, 169, 177, 178, 194 digital compact, 137–144, 146, 148, 151, 162–165, 168–170, 173, 175, 176, 178, 184, 186, 188, 192 digital SLR, 103, 141–144, 164 webcam-type, 21, 169, 176, 178, 198 Carrington, R., 61, 70 Catadioptric telescopes, 22, 24–27, 35–37, 145 Central meridian, 74, 76–78 Chromosphere, 5, 6, 9, 10, 22, 101–134, 168–172, 181 CMEs See Coronal mass ejections (CMEs) Colour (of digital image), 194 Compact cameras See Cameras Compact flash cards See Memory cards Contrast (in image processing), 33–35, 38, 44, 47, 48, 52, 97, 98, 108, 111, 112, 115, 117–120, 144, 145, 150, 151, 160, 164, 168, 169, 171, 183, 185, 186, 188–194, 196 L Macdonald, How to Observe the Sun Safely, Patrick Moore’s Practical Astronomy Series, 211 DOI 10.1007/978-1-4614-3825-0, © Springer Science+Business Media New York 2012 free ebooks ==> www.ebook777.com 212 Index Convective zone (of sun), 4, 47 Core (of sun), 3, 43 Corona, 5, 6, 10–12, 16, 101, 103, 105, 107, 119, 127, 153 Coronado CEMAX eyepieces, 116 Coronado filters, 111, 115 Coronagraph, 6, 101, 103, 107, 108, 119–121, 171, 172, 196 Coronal holes, 11, 13, 14 Coronal mass ejections (CMEs), 11–13, 15, 16 Cropping, 187, 189, 190 D DayStar filters, 108, 109, 113, 114, 116–119, 124, 125 Deslandres, H., 107 Dobsonian mounting, 25, 151 DSLR cameras See Cameras E Eclipse (of moon), 5, 6, 119, 120, 153, 167, 174 Eclipse (of sun), 4–6, 10, 11, 32, 34, 37, 38, 101, 107, 119, 120, 153, 174, 196 Energy rejection filter (ERF), 109, 116, 117, 119, 124 Equatorial mounting, 20, 25, 26, 68–70, 80, 120, 145, 179 ERF See Energy rejection filter (ERF) Eruptive prominences, 126 Etalon, 108, 109, 111–119, 122, 124 Exposure (in solar photography), 24, 135, 137, 141, 145, 146, 150, 159, 163 Eye, danger to from Sun, 17, 18 Eyepiece projection, 148, 150, 156–160, 168, 173, 180 Eyepieces (for solar projection), 30, 31, 89 F Faculae, polar See Polar faculae Filaments, 50, 51, 104, 105, 107, 111, 115, 118, 119, 125–131, 169, 170 Film, photographic, 32, 63, 138 Filters Baader (white light), 34, 125 Ca-K, 106, 124, 125 eyepiece (DANGER!), 18, 22, 31, 36 glass, 25, 34, 35, 37, 60, 98, 145, 147 H-alpha (see H-alpha filters) Mylar, 32–35, 39, 59, 98, 122, 145, 168, 193 photographic film (DANGER!), 32, 35, 147, 148, 168 smoked glass (DANGER!), 32 in solar photography, 24, 34, 135, 137, 145–147 Flares, solar, 9, 15, 61, 105, 126, 131 Flocculi, 105 Focusing (for photography), 123, 135, 142, 143, 147, 160, 164–166, 169 Focusing magnifiers, 142, 166 Focusing screen (in DSLR cameras), 164, 165, 167, 170, 175 Fork mountings, 26 Fringe-Killer filter, 31, 168, 180, 194 G Geomagnetic storms, 13–16, 134 Glass filters, 34, 35, 60, 145, 193 Go To telescopes, 22, 26 Granulation, solar, 31, 47 Graphs of solar activity, 94 H Hale, G.E., 107 H-alpha See Hydrogen-alpha H-alpha filters, 22, 93, 105–110, 113–126, 128, 130, 131, 133, 135, 137, 169, 181, 183 Hedgerow prominences, 126 Herschel wedge, 36, 37, 44, 125, 144, 145, 168, 179 Hodgson, R., 61, 62 Hydrogen-alpha (H-alpha), 5, 60, 80, 93, 102, 135, 174 I Image processing software, 174, 177, 186, 187 Imaging Source (webcam-type cameras), 177, 178 Interference filters, 47, 102, 107–110, 168, 180 J Janssen, P., 107 L L0, 74, 76–78 Light bridge, 54, 62, 88, 93, 98 Limb darkening, 48–49, 53, 59, 140, 159, 191 www.ebook777.com free ebooks ==> www.ebook777.com Index Little Ice Age, 13 Lockyer, N., 107 Lumenera (webcam-type cameras), 177, 178 Lunt filters, 116, 122 Lyot, B., 107 M Maksutov telescope, 24, 25, 27, 31, 35, 68, 69, 84, 144, 153, 154 Maunder, E.W., 13, 78 Maunder minimum, 13 McIntosh sunspot classification system, 57 MDF See Mean Daily Frequency Mean Daily Frequency, 84–86 Memory cards, 139, 160, 173 Motor drives (for telescopes), 28, 67, 135, 166, 167 Mylar filters, 32–35, 193 N Naked-eye sunspots, 37, 98–99 Newtonian telescope, 23, 157 NexImage (webcam by Celestron), 176, 177, 180, 182, 183 O Off-axis mask, 23–24 Orientation of sun’s image, 26, 69, 70, 72, 129, 191 P P See Position angle Passband, 108–119, 124, 125, 168 Penumbra, 50–57, 62, 68, 86, 88, 89, 160 Penumbral filaments, 50, 51 Photosphere, 4–7, 11, 48–51, 53, 54, 59, 62, 88, 101, 102, 169, 170, 191, 192 Plages, 104–106, 115, 118, 119, 131 Polar faculae, 59–61, 78, 97, 98 Pores, 53, 54, 56, 78, 86, 88, 89, 183 Position angle, 72–76, 90, 97 Pre-filter See Energy rejection filter Prime focus, 30, 122, 123, 150–155, 160, 168, 180 Projection box(es), 20, 28–31, 44, 45, 47, 60, 61, 64–67, 70, 86, 97 Projection grid, 64–67, 90, 97 Projection method, 23, 30, 31, 45, 61, 64–80, 89, 98, 128, 150, 190 213 Prominences, 10, 11, 22, 93, 102–105, 107, 108, 110, 111, 115, 117, 119–121, 125–131, 135, 168, 169, 171, 172, 180, 181, 183–186, 194–196 Q Quiescent prominences, 125–127, 130 R R See Relative Sunspot Number Radiative zone, Reflector (telescope), 19, 22–25, 27, 31, 37, 68, 84, 151, 153, 180 Refractor (telescope), 8, 19–31, 33, 37, 44, 46, 47, 50, 61, 68–70, 84, 87, 97, 103, 109, 112, 114, 115, 119, 120, 123–125, 135, 144, 145, 147, 153–159, 162, 165–171, 175, 176, 178–180, 183, 188–190, 194 Relative Sunspot Number, 83, 86–96, 103 Report forms, 91, 92, 94 Rotation number, 70, 74 S Satellites, effects of solar activity on, 9, 11, 13, 15 Scanning images, 70 Schmidt-Cassegrain telescope, 24, 27, 31, 68, 69, 84, 117, 144 SCT See Schmidt-Cassegrain telescope Seeing, 5, 14, 42–44, 48, 50, 61, 62, 70, 80, 87–89, 93, 97–99, 106, 120, 122, 136, 138, 145, 146, 159, 160, 173–175, 179, 180, 182–184, 190 Self-timer, 141, 164 Sharpening digital images, 192–193 Slow motions (on telescope mount), 20, 26, 47, 67, 68, 115, 145, 166 Solar and Heliospheric Observatory (SOHO), 9, 11, 12 Solar cycle, 8, 9, 11, 14, 16, 50, 58, 78, 79, 84, 90, 94, 96, 97, 102, 131 Solar Dynamics Observatory (SDO), Solar finderscopes, 45, 46 Solarscope filters, 109, 113, 114, 116, 122, 123 Solar telescope, 34, 106, 108, 110–112, 115 Solar wind, 6, 11–13, 15 Spectroheliograph, 107 Spectrohelioscope, 107, 108 Spectroscope, 107 Spicules, 127, 181 free ebooks ==> www.ebook777.com 214 Index Spörer, G., 78 Spörer’s law, 78, 90 Stars (compared with sun), 1–3, 6, 17, 22, 120, 171 STEREO spacecraft mission, 16, 55 Stonyhurst discs, 71, 72, 74, 76, 77, 86, 90 Sun diagonal See Herschel wedge Sunspot cycle, 7–9, 13, 70, 71, 78, 79, 96, 97, 125 Sunspot groups, 7, 9–11, 15, 37, 47–51, 53–62, 75, 76, 78–80, 83–87, 89, 93, 96, 98, 99, 104, 105, 118, 126–128, 130–135, 145, 146, 148, 156, 158, 159, 166, 174, 186 bipolar, 51, 53, 55–57, 75 Sunspots classification, 55–59 longevity, 54 magnetic fields, 59 numbers, 53, 55, 59 positions, 63, 64, 67, 71–74 temperature, 7, 13 T T-adapter, 154 Teleconverter, 152, 154–156, 159, 160, 167, 169, 188, 189 Tele-extender, 158 Transition region, 6, Transition Region and Corona Explorer(TRACE) spacecraft, T-ring, 120, 154, 156–158, 164 U Umbra, 50–56, 77, 86, 88, 93, 99 Unsharp mask, 189, 193 W Weather, sun’s effect on, 1, 12, 13, 15, 43, 44 Welder’s glass, 37, 99 White-light flares, 61, 62, 80, 93, 97–98, 131 Wilson, A., 52 Wilson Effect, 52, 53 Wolf, J.R., 87 Wolf Number See Relative Sunspot Number Z Zurich Number See Relative Sunspot Number www.ebook777.com ... diagram showing the structure of the Sun Total solar eclipse, photographed by Derek Hatch on August 1, 2008, showing the extensive white corona around the black silhouette of the Moon The Sun s... there is all the more need for an up -to- date guide to show the amateur what to look for on the Sun, how to record observations, and what equipment to use This second edition is aimed at the amateur... Film filter, (b) The image cropped to center the Sun s image and exclude some of the black background, (c) The image flipped to show east to the right, (d) The brightness decreased by 20 points and