Further Readings

Perhaps the best way to appreciate the magnitude of the debates and controversies associated with early sunspot observations is to turn to the early seventeenth century literature on the subject. The following still makes for fascinating reading today:

Galilei, G., Dialogue Concerning the Two Chief World Systems, trans. S. Drake, University of California Press, 1967.

(see in particular the First Day). Galileo's views on sunspots are discussed in greater length in his so-called Letters on Sunspots, excerpts of which have also been translated by S. Drake in his Discoveries and Opinions of Galileo (Doubleday, 1957). The following is a more recent historical account of the development of solar physics from the early seventeenth century to the present:

Hufbauer, K., Exploring the Sun: Solar Science since Galileo, Johns Hopkins University Press, 1991.

On the influence of solar variability on the Earth's climate, see

White, O. R. (ed), The Solar Radiative Output and its variations, Colorado Associated University Press, 1977.

More recently, the National Research Council published a report entitled Solar Influences on Global Change (National Academy Press, Washington D.C., 1994). Watch also for a book by D.V. Hoyt, soon to be published by Oxford University Press. The following are two contemporary textbooks devoted exclusively to solar physics:

Stix, M., The Sun: An Introduction, Springer, 1989

Foukal, P. V., Solar Astrophysics, Wiley Interscience, 1990.

Both these texts discuss at some length the physical nature and mode of operation of the solar dynamo. To get a feel for contemporary research directions in solar physics, the interested reader may wish to browse through

Strong. K., Saba, J. and Haisch, B., (eds), The many faces of the Sun, 1995.

The Sun is a rather ordinary star, but being so much closer to even the next nearest star makes it an invaluable benchmark against which to test astrophysical theories. Introductory textbooks on astronomy and astrophysics abound; at the pre-calculus level, we recommend

Abell, G. O., Morrison, D. and Wolff, S. C., Exploration of the Universe (fifth edition), Saunders College Publishing, 1987".

while readers comfortable with basic calculus may opt for

Shu, F., The Physical Universe: An Introduction to Astronomy, University Science Books, 1982.

Note finally that daily solar images in H, X-rays, etc, can be viewed on the World Wide Web. As of March 1995 such images are available from the Solar Data Analysis Center at NASA's Goddard Space Flight Center, and from the Space Environment Laboratory of the National Oceanic and Atmospheric Administration. Daily coronal images are soon to be made available online by the High Altitude Observatory.