July 9, 2016

Nearest Star

Nearest Star

Nearest Star: The Surprising Science of our Sun, 2nd edition

by Leon Golub and Jay M. Pasachoff

Published by Cambridge University Press (2014)



see also their more advanced book, a text:

The Solar Corona

The Solar Corona

Published by Cambridge University Press, © 2010 by L. Golub and J. Pasachoff

Authors’ webpage for the book


Journal of the British Astronomy Association Review

Review by Barry Kent

This is a carefully composed, very readable account of the physics of the Sun, written with the non-specialist in mind. There are essentially no equations – instead the relationships between relevant phenomena are explained but without any loss of rigour. The explanations are easy to follow but do not talk down to the readership and do not resort to the dreadful analogies that so bedevil many ‘popular science’ books. So, that being said, I would not describe it as popular science but solar science for the logical and maybe rational non-specialist. For me, writing as a specialist of sorts, with 30 or so years’ experience at the instrumentation end of space science, even I learned a new word – syzygy – the alignment of three celestial objects, which if nothing else has to be worth about a million points in Scrabble.
One could make niggly uncharitable remarks about the US-centric text – for example, the SOHO spacecraft gets quite a lot of coverage and yet ESA, NASA’s partner in the production of this most successful scientific spacecraft, doesn’t even merit an acknowledgement; which is unusual as the authors have been quite thorough in acknowledging the main intellectual source of particular ideas or discovers of phenomena. I imagine that NASA was paying some of the bills, but that is a minor quibble about an otherwise thoroughly readable and enjoyable account.
The charity of writing is apparent in so many examples; from the description of the linking of light and colour to form spectra – “But we do not see colour flashing past us in the air …” – to the physical properties then derived. Other phenomena such as limb darkening , solar neutrinos, the formation of the elements are all excellent stuff; and if you want more, each chapter ends with suggested further reading.
Another minor quibble comes from the chapter dealing with descriptions of space missions. For a few pages in Chapter 6, in which various space missions are described, the previously clear human voice degenerates into corporate-management speak. The Japanese spacecraft Hinode is described as “an excellent opportunity for highly leveraged US participation in a major mission that is greatly advancing our understanding of the crucial first link in the Sun Earth connection”. Most of those words are padding and “highly leveraged” presumably means the US worked a scam that got it some great science at little cost to itself. I suspect that the interaction was much more nuanced than the naked opportunism implied by these words, and that some mutual scientific benefit might also have been a result worth mentioning, if only to illustrate the international cooperative nature of solar science (a point the authors actually make themselves in one of the readable chapters).
One final example: we learn that the Heliseismic and Magnetic Imager on the Solar Dynamics Observatory enables “line of sigh magnetograms with an optical channel for full Stokes polarisation measurements and hence [yes, hence] vector magnetogram determination”. Stokes polarisation measurements had not been discussed and certainly not explained at that point – or indeed anywhere else in the book – even the handy four-page glossary fails. It is as if a different author had been brought in to write that stuff – somebody, who had not been briefed on the ‘science for the non-specialist’ target readership. It is a great pity as this chapter diminishes the opinion built up in the previous chapters of the authors as fine educators.
Fortunately Golub and Pasachoff return to their previous excellent form with Chapter 7, which is a very considered discussion on the Sun’s influence on climate, which they then use as an example of the way science works in general. Incidentally, this is one of the clearest expositions that I have read on climate change and the difficulties in assigning causes and predicting likely outcomes.
The overwhelming impression from reading this book is of clarity and economy; clarity of explanation and expression and also economy of description; nothing is said that is not needed, and no image is superfluous, each one used to illustrate a particular feature being described. So apart from the few aberrant pages in Chapter 6, I would recommend this book to specialist and non-specialist alike as a fine, ‘non-preachy’, and concise account of the current state of knowledge of the workings of our local star, the Sun, and also of the instruments by which that information has been obtained. Unusually for such non-specialist books it maintains a running theme of highlighting the intellectual process being followed to obtain this knowledge, and as such is a valuable addition to books on the more general topic of ‘doing science’.

The following refers to the 1st edition:



Nearest Star: The Exciting Science of Our Sun (1st edition)

by Leon Golub and Jay M. Pasachoff

Published by Harvard University Press May 2001


“A book written with both knowledge of and affection for the subject, so that portions of it are almost as warming as the sun itself.”
Virginia Trimble, University of Maryland and University of California at Irvine

“It’s easy to take for granted our nearest star, the star that provides us with heat and light, ingredients we need for our existence. But with clear prose, the authors bring us an exciting and important tale of what we know about our vital neighbor, how we know it, and what we’re still learning at the forefront of research.”
Wendy Freedman, Carnegie Observatories, a leader of the Hubble Space Telescope’s Key Project on the Cosmic Distance Scale

“The Sun is life, and for us Earthlings it anchors the most important real estate in the universe. Until this century we didn’t have a clue as to how the Sun works. Golub and Pasachoff–expert solar physicists–unveil in everyday language the Sun’s wonderfully energetic alchemy and the many ways it influences our lives. They provide a harmonious balance between historical reflection and cutting-edge science.”
Leif J. Robinson, Editor Emeritus, “Sky & Telescope” magazine

“The State of the Sun: Here, in a single, beautifully written volume, Golub and Pasachoff have brought us all up to date about the most important star of all. This book should appeal to everyone who have gone outside, felt the heat of the Sun, and wanted to learn more about it. The chapter on eclipses is particularly good, which is not surprising considering that Pasachoff has seen more eclipses than anyone else I know. Both authors are expert and their words are easy to understand, enjoy, and learn from.”
David Levy

“A happy life here on Earth depends on many things – sufficient food, clean water, good health, a friendly environment, harmony, beauty. But all of these are insignificant compared to one more – sunlight. Without the sun our Earth would be a dead and frozen wasteland. This excellent book by two eloquent experts describes our wondrous star. It is huge, complex, turbulent, constantly erupting and ultimately evolving. – An important star, an important book.”
Paul Hodge, Professor of Astronomy, University of Washington, Editor, The Astronomical Journal

“This timely book considers the latest achievements and advances in solar physics. Written by two of the world’s most active and brilliant astrophysicists, it offers clues that may lead to the resolution of many of the most fundamental questions facing solar physicists, including the hotly debated question of the nature of the relationship between the sun and the earth.”
Serge Koutchmy, “Directeur de Recherche” at Paris Institut d’Astrophysique; CNRS-France

Selected Reviews

S.E.C. User Notes Space Environment Center, NOAA, Issue 39, January 2003

Review from Sky & Telescope, December 2002

Two solar astrophysicists–Golub from the Harvard-Smithsonian Center for Astrophysics and Pasachoff from Williams College–profile current knowledge (and unsolved problems) about the Sun. (Pasachoff is also, he notes, a veteran of 31 solar eclipses, which makes the chapter on eclipses especially vivid.) More than other books on the Sun, Nearest Star focuses on the contributions from satellite observatories, with much discussion about current and planned projects. While the old Harvard Books on Astronomy series is defunct, this volume follows in much the same spirit, being well written for the interested lay reader.


Review from the Times Higher Education Supplement (London), 20 September 2002

…its details about eclipses capture a lot of the excitement familiar to those of us caught up the fervour surrounding the 1999 eclipse…. This is not surprising as the authors are among the world’s leading experts in observing eclipses and have distinguished careers in studies of the solar atmosphere.

Global warning is a daily topic of conversation…. Golub and Pasachoff’s book rises to the challenge with some accurate and down-to-earth text about climate, as well as about attempts made by United Nations-sponsored meetings to limit the production of greenhouse gases….

I was impressed by the descriptive nature of the text, which has no mathematics or complex plysics. This is a book for amateur astronomers and scientists who want to know what are the latest findings about the Sun and about some of the developments that led to them.


Review from The Physics Teacher, February 2002, p. 127

The authors, who are well known in the solar-research community, have written a book for nonscientific readers. However, I suspect it will be read by astronomy students and teachers for the new insights it gives about solar physics….
….Astronomy lends itself to popularization because its discoveries are often found in astonishing images and startling theories that can be discussed without equations. In this “golden age of astronomy,” many books and articles bring us news of distant cosmic phenomena, but Nearest Star tells us about the latest discoveries in our own backyard in a freshing and insightful way. This is a gem of a book. Read it for information and pleasure.

James O’Connell
Frederick Community College


Review from Physics Today, November 2001, pp. 59-60

Nearest Star: The Surprising Science Of Our Sun tells the story of our most important star, the Sun, and its relationship to our most important planet, Earth. It is a story with many facets, and multiple links to fundamental physics that might surprise as well as engage the reader. The book is beautifully written and conveys the love that the authors have for the subject.
…Together, they are uniquely qualified to write a book on the Sun, and they have produced a truly fascinating tour, complete with an outstanding set of images.
…This book can appeal to a wide audience…. Overall, the grand scope of the book will engage folks who enjoy keeping abreast of current science.
…it is gratifying to see a discussion of the aurora that gets the basics right….
…In sum, Nearest Star provides an excellent overview of our current understanding of the Sun and its effects on Earth.

Ramon E. Lopez
University of Texas at El Paso



Shedding light on a golden age

Book review by John H. Thomas, U. Rochester, from NATURE, Sept. 13, 2001

[John Thomas was Chair of the Solar Physics Division of the American Astronomical Society and is now Scientific Editor of The Astrophysical Journal.]

Nearest Star: The Exciting Science of Our Sun
by Leon Golub & Jay M. Pasachoff
Harvard University Press: 2001. 267 pp. $29.95

Solar physics is in something of a golden age….

Nearest Star beautifully presents these and other recent advances for the = general reader, while also giving a good historical perspective on our = study of the Sun. The authors are especially well qualified to write a = popular book on this topic….

A timely feature of the book is its excellent chapter (entitled “Fire and Ice”) on the Sun’s influence on the Earth’s climate. This chapter contains a thoughtful discussion of the climate system and global warming and shows why we need to have a better understanding of the effects of solar variability on our climate before we can sort out the man-made effects.

Nearest Star is an up-to-date, authoritative and entertaining introduction to the Sun for the general reader. It represents popular science writing at its best – expert authors writing in a clear and lively style, without oversimplification, engaging the reader’s creative thinking and imagination.


“Our Day Star,” a book review by J. M. LaRoche

An illuminating resource about the Sun for the general audience, has been created by astronomers Golub and Pasachoff. Numerous illustrations, photos, & links augment its clear text.

This reader found the book to have just the right balance between enough technical detail and too much. It is almost a fast paced read. One might almost imagine an adventure story. For those whose appetites have been wetted there are web sites, magazine articles and other books cited to pursue even more information about our star. There are also maintained websites for the book.

[The whole review is at http://www.lunarpages.com/netefx/info/rvw/nearest_star_pr.html


Kirkus Reviews, March 1, 2001, Starred review

*Golub, Leon, & Jay M. Pasachoff
NEAREST STAR: The Surprising Science of our Sun
Harvard Univ. (304 pp.) $29.95
May 2001
ISBN: 0-674-00467-1

It may be “the story of one tiny star among the trillions that have come and gone during the past 15 billion years,” but it sure makes for soul-stirring, mind-blowing reading.
Golub (Harvard-Smithsonian Center for Astrophysics) and Pasachoff (Astronomy/Williams Coll.) have put together a superb profile of the sun. They don’t assume any special knowledge on the part of their readers, so they explain their subject starting with broad overviews and theories–such as the birth of the sun, its composition, and the various tools used to understand its history and makeup (including spectroscopy, high-resolution imaging, and helioseismology). Although the progression into more complex material is gradual, the authors don’t cut readers much slack: There may be no mathematical equations to wrestle with, but there is much discussion of parallax and yottawatt, Maunder minimums and limb darkenings, faculae, auroral electrojets, and the Transit of Venus. These are conducted in concise language, however, and they glide smoothly between fundamental questions (Just how come that great roiling sea of gas keeps on burning? Are stars solid?) and more arcane but immediately relevant topics (such as the nature and consequences of solar wind on Earth’s magnetic field). Discussions of prominences, flares, and spicules can take your breath away, as will the considerations of zodiacal light and sunspots and total eclipses (although there is no mention of everyone’s favorite, the green flash). A final overview of the sun’s role in climate, and an outline of how humans have, in their ineptitude and to their disadvantage, overwhelmed certain solar influences wrap the proceedings up nicely.
The sun is simply peerless from any angle and this enlightening biography shows it in all its glory-as bright as daylight. (Color and b&w illustrations)


Booklist – March 1, 2001

Golub, Leon, and Pasachoff, Jay M.
Nearest Star: The Surprising Science of our Sun, May 2001, 304p. illus.
Harvard, $29.95 (0-674-00467-1) .523.7.

For an object that has remained generally the same for billions of years (without such equability, life on Earth never could have flowered and thrived), the sun is stunningly turbulent and changeable. Golub and Pasachoff, who study the sun professionally, offer amateurs a brilliant, richly illustrated survey of the current state of solar knowledge. That knowledge is amassed most vitally from analyzing the spectra of light, whose varying wavelengths dictate how deeply into the sun astrophysicists may observe. Another source of information is, amazingly, sound and seismic waves, and solar eclipses still attract scientists who study the corona. Although we know now that nuclear fusion powers the sun’s pyrotechnics, the detailed workings of its core still puzzles us, for the core produces fewer neutrinos than had been theorized, and its causation of the sun’s enormously powerful magnetic field is a complete mystery, as is its relation to the 11-year sunspot cycle. Golub and Pasachoff described the sun’s dynamism and effects on Earth in a crystalline, nontechnical fashion perfectly suited to non-specialist readers. -Gilbert Taylor YA/L: For advanced students and well-versed teen astronomy fans. SZ.


Publisher’s Weekly – May 2001

The Surprising Science of Our Sun
Harvard Univ. $29.95 (304p) ISBN 0-674-00467.

Taking advantage of the increased attention as the sun reaches the peak of its 11-year sunspot cycle, Harvard-Smithsonian astrophysicist Golub and Williams College astronomy professor Pasachoff deliver a clear, detailed and broadly informative overview of the scientific study of our “nearest star” and its effects on our planet. Other recent books cover some of the same territory in more detail (the energy production and internal structure of the sun and other stars in Stardust by John and Mary Gribbin and The Magic Furnace by Marcus Chown; the vulnerability of modern technology to intense solar activity in The 23rd Cycle by Sten Odenwald), but this book shines in its discussion of the properties of the sun’s turbulent outer layers (chromosphere, photosphere and corona). It provides space-and astronomy-loving readers in-depth information about the many challenging projects that produced or are producing that knowledge, about advanced projects on the drawing board or in conceptual stages and about Web sites where readers can find more details and up-to-date developments. On the human level, the authors describe practical techniques to enhance the thrill of observing a total solar eclipse. The book ends with a discussion of the interaction between solar and terrestrial phenomena, comparing human contributions to climate change to the climatic influence of solar variation Amateur astronomers will learn much from Golub and Pasachoff’s study. Illus. (May)


New Scientist, 26 May 2001

“Nearest star” by Leon Golub and Jay Pasachoff,
$29.95, Harvard, ISBN 0674004671

The subtitle of Nearest Star is “The surprising science of our Sun.” And it is surprising: our knowledge of this normal dwarf star that happens to be all-important to life on Earth is very far from complete. Many puzzles remain, even if we know far more than we did a few years ago, before data from spacecraft became available. In any case, Leon Golub and Jay Pasachoff are splendid guides to the subject, as both are highly distinguished American astronomers who have paid special attention to the Sun.
Nearest Star is a comprehensive survey, dealing with all aspects of solar research. It is well written and well illustrated, and there is a good glossary and a useful bibliography. It is probably not a book for the complete beginner, or for the amateur observer using modest equipment; it is not intended to be so. If, however, you are looking for a reliable, up-to-date and very readable account of modern solar science, with special emphasis on Earth-Sun relationships, then this is one for you.

Sir Patrick Moore is an astronomer


Williams Alumni Review, Summer/Fall 2001, p. 10

Nearest Star: The Surprising Science of Our Sun By Leon Golub and Jay M. Pasachoff, Field Memorial Professor of Astronomy. Harvard University Press, 2001. 267 pages. $29.95. A review of what history and science have revealed about the sun, from the first cursory observations to state-of-the-art instruments.


Astronomy magazine – July 2002

Nearest Star: The Surprising Science of Our Sun

Leon Golub and Jay M. Pasachoff, 267 pages, Harvard University Press, Cambridge, Massachusetts, 2001; ISBN 0-674-00467-1; hardcover, $29.95

Many ancient cultures worshipped the sun as a god, a giver of life. While most of us have long given up the notion of the sun as a deity, we cannot deny that life on our planet owes its very existence to it. The sun provides Earth with heat and light. Plants produce the oxygen we breathe with the help of sunlight. The complex interaction between the sun’s radiant energy and our atmosphere is responsbilbe for our “hospitable” environment. Despite our apparent good fortune – having just the right place in the solar system around just the right kind of star – the sun really is just an “average” star, only one among billions in the Milky Way Galaxy. All these other stars, however, appear to us as mere points of light in the sky, even in the most powerful telescopes. The proximity of our sun provides us with a unique opportunity to study a star up close.

In “Nearest Star”, two of the world’s leading solar scientists give us a fascinating and informative account of our sun as a star. Leon Golub, an astrophycist at Harvard University, and Jay M. Pasachoff, Field Memorial Professor at Williams College, trace the history of solar studies from the first visual observations to the latest state-of-the-art space missions. The authors examine the basic physical parameters of the sun and its origin and evolution. They discuss in great detail the structure of the sun, how it works, and how this information is derived both from the things we can see and those we can’t. There is a wonderful discussion of eclipses and their scientific value, replete with black-and-white images. Their grand finale is two chapters in which they examine the sun’s role in shaping the climate on Earth and the effect of space weather on Earth.

Golub and Pasachoff do not simply present an account of scientific fact. Rather, they show us how the process of science works. For example, in discussing the structure of the sun, they examine the concept of stellar opacity – which can be thought of as a resistance of matter to the flow of radiation. They explain how opacity effects lead to an observed darkening of the sun’s disk going from the center out to the limb, an effect called “limb darkening.” They also show how opacity affects what is seen in the region of spectral lines such as the calcium H and K lines and how these opacity effects are used to probe the structure of the sun at various depths. Throughout, the authors emphasize why and how we study the sun at many different wavelengths and what has been discovered by looking at the sun in each of these wavelength regimes.

“Nearest Star” is a delight to read. Golub and Pasachoff transmit not only their obvious expertise but also a genuine affection for the subject. The book is richly illustrated with both black-and-white images and a nice selection of color plates; it also has a necessary glossary of physics and astronomy terms. A particularly nice feature of “Nearest Star” is the critical examination of just how the sun influences Earth’s climate and the role of both industrial emissions and solar factors on climte changes.

“Nearest Star” will surely leave you with a renewed appreciation for the beauty, complexity, and importance of our nearest star, the sun.

Jennifer Birriel, Morehead State University


Harvard University Press Webpage ordering

ISBN 0674004671 (cloth) — $29.95,    ISBN 0-674-01006-X (paper) — $16.95Links to Solar Websites, including Daily Images and Spacecraft Descriptions

Other books by Jay M. Pasachoff


Articles and News Updates

Solar Constant On-Line

The latest values of the solar constant as measured by the VIRGO experiment on SOHO, along with past measurements from several spacecraft, are available on line at
http://www.pmodwrc.ch/solar_const/solar_const.html from the World Radiation Center in Davos, Switzerland.


Updates and Errata for the Paperback Version of the 1st Edition (2002)

On p. 2, line 5, of Nearest Star, “one million” should actually be “one billion.”

p. 15
The increase in intensity is the square of the ratio of the primary mirror diameter to the minimum secondary diameter, neglecting the shadowed portion of the primary. The minimum diameter needed for the secondary, in turn, is related to the secondary’s focal length.

p. 21
Fig. 1.10 The refraction in the prism itself of the incoming slit of light after it hits the first face of the prism is not shown.

p. 44
Figure 2.6 dates from before AD 1630, well before the dates usually listed for the Maunder minimum of 1645-1705. Sunspot records from that time are sketchy, and the reported lack of sunspots could already have started. Avercamp’s and Bruegel’s pictures of ice-skating on canals from this period are often used to illustrate the point we are making. The canals freeze occasionally now, but not often.
Whether the Maunder minimum really occurred is still debated as is the quesiton of whether the cold weather was global or was restricted to Western Europe.

p. 46, line -5
add: European Space Agency instruments will be sent aloft to measure the solar constant from the International Space Station.

p. 54, Fig. 3.1: This image is printed as a negative.

p. 55, Fig. 3.2: Limb darkening is correctly shown on the drawing of the surface in the left half of the image. The shells get blacker as you go deeper into the sun only as a display on the printed page; actually, the temperature increases inward, as is correctly explained in the text.

pp. 61 and 80: solar parameters in addition to atomic ones determine visibility of spectral lines, as is correctly discussed in various places.

Fig. 3.19, p. 89:
As is specified correctly in the caption but wrong in the labels on the spectrum, the observed h line (2803 A) of ionized magnesium is at a longer wavelength than the k line (2795 A).

p. 103
The figure (Plate IX) was arranged vertically rather than horizontally. Change lines 12-13 from “top left and bottom left” to “first and third”. We also need to change “bottom right” to “last”.

p. 109, first word: “2solving” should be “solving”

p. 111, line -13: Change “… enormous number of different waves …” to “… enormous number of different sound waves …”.

p. 115, line -8: change “… lower the temperature of the Sun (this is why sunspots appear dark) and this in turn changes the sound speed.” to read “.. alter the propagation of sound waves through the subsurface regions.”

pp. 119-121
Serge Koutchmy points out that the Babylonians did not use the term saros as we use it today. It was applied to something else, and was in terms of the lunar calendar.
See “Les eclipses de Soleil” of the Bureau des Longitudes, France (EDP Sciences 1999), in a chapter by Michel Lerner and Denis Savoie.

pp. 126-127
Serge Koutchmy has pointed out that Gordon Newkirk did not invent the radial-filter system, which was used as early as 1900 and then reinvented for the eclipse of 1961 by Laffineur in France. Koutchmy has himself taken excellent series of radial-filter images. Newkirk is properly credited with the coronal-camera system that successfully used a radial filter at a series of eclipses.
See “Total Eclipses of the Sun” by S. Koutchmy and P. Guillermier (Springer-Praxis, 1999).

p. 173
change “The first mission in the line of solar-terrestrial probes is …” to “One of the missions in the line of solar-terrestrial probes is …”, referring to the STEREO mission.

p. 181
Add: The European Space Agency’s Solar Orbiter is to orbit the Sun relatively closely in the 2022-2025 time frame. Because it will be only 1/4 of Earth’s distance from the Sun, its images will be better than current capabilities.

p. 196, line -4: “Opposite charges” should be “like charges repel.”

p. 216, paragraph beginning “In the United States …” add at end of paragraph “(… is not in sight), and in 2001 the United States renounced its signature on the treaty.”

p. 216, line 12: change “was settled” to “was apparently settled”

p. 217, line 18 (i.e., at end of paragraph): add “The Dutch company Royal Dutch Shell, has created a division named Shell Hydrogen to develop hydrogen as a fuel source.”

p. 217, line 21 (after “… for their implementation): add “A very small improvement in fuel effiency standards for cars and trucks of only a few miles per gallon could sharply reduce the U.S. dependence on imported oil.”

p. 217, line 5: change “has not changed” to “has actually declined.”

p. 220, line 10, after the sentence ending
” … from some location on the Sun.” Please add this sentence: “Such a suggestion had been made as early as 1908 by Kristian Birkeland to explain the origin of the aurora.”

p. 222, line 9, after “… not well received.”
please add: “Chapman in particular argued against it, as he had argued earlier in the century against Birkeland’s explanations for magnetic storms.”

p. 221, last sentence of last paragraph: all the “billionth”‘s should be “millionth”‘s.


Updates and Errata after the Paperback Version of the 1st Edition

p. 44, footnote


Douglas V. Hoyt and Kenneth H. Schatten

Abstract. In this paper we examine how well the Sun and sunspots were observed during the Maunder Minimum from 1645 to 1715. Recent research has given us the date of observations by Hevelius, Picard, La Hire, Flamsteed, and about 70 other observers. These specific obsevations allow a ‘lower estimate’ of the fraction of the time the Sun was observed to be deduced. It is found that 52.7% of the days have recorded observations. There are additional 12 observers who provide general statements that no sunspots were observed during specific years or intervals despite diligent efforts. Taking these staements to mean, unrealistically, that every day during these intervals was observed, gives an ‘upper estimate’ of 98% of the days. If the general statements are relaxed by assuming that 100+/-50 days per year were actually observed by these diligent observers, than our ‘best estimate’ is that 68%+/-7% of the days during the Maunder Minimum were observed. In short, this supports the view that the Maunder Minimum existed and was not an artifact of few observations. Some sunspots are probably still missed in modern compilations, but the existence of a prolonged sunspot minimum would not be threatened by their discovery in future research. Additional support for intense scrutiny of the Sun comes from a report of a white-light flare in 1705 and from the numerous reports of new sunspots entering the disk of the Sun.

from the scientific journal “Solar Physics,” vol. 165: pp. 181-192, 1996.

p. 217, line 18 (i.e., at end of paragraph): add “The Dutch company Royal Dutch Shell, has created a division named Shell Hydrogen to develop hydrogen as a fuel source.”

p. 217, line 21 (after “… for their implementation): add “A very small improvement in fuel effiency standards for cars and trucks of only a few miles per gallon could sharply reduce the U.S. dependence on imported oil.”

Solar Dynamics Observatory flare image highly processed, similar to eclipse-image processing


p. 132, fig. 5.3: eclipse date (in the figure itself) is 1979 Feb *26*
p. 177, l. 22: NASA’s first successflul (should be: success*ful*)
p. 237, fig. 7.7, 3. Variation in ellipticity of orbit: for the
elliptical orbit the perihelion distance to the sun is always smaller
than the circular orbit distance. In the picture, should be
located at one of the foci of the elliptical orbit.

JBAA Jun 2015

High-Energy X-ray View of the Sun with NuSTAR



X-rays stream off the sun in this image showing observations from by NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR, overlaid on a picture taken by NASA’s Solar Dynamics Observatory (SDO). This is the first picture of the sun taken by NuSTAR. The field of view covers the west limb of the sun.


The NuSTAR data, seen in green and blue, reveal solar high-energy emission (green shows energies between 2 and 3 kiloelectron volts, and blue shows energies between 3 and 5 kiloelectron volts). The high-energy X-rays come from gas heated to above 3 million degrees.


The red channel represents ultraviolet light captured by SDO at wavelengths of 171 angstroms, and shows the presence of lower-temperature material in the solar atmosphere at 1 million degrees.


This image shows that some of the hotter emission tracked by NuSTAR is coming from different locations in the active regions and the coronal loops than the cooler emission shown in the SDO image. Note that NuSTAR’s field of view for these observations covered only the upper portions of the SDO image.