Sun book: handsome, factual, dull; Fire of Life: The Smithsonian Book of the Sun. Washington: Smithsonian Exposition Press (distributed by W. W. Norton & Co., New York). $24.95.

That the sun is at the center of things in our planetary system, that it is giver of all earthly life, are the preeminent truisms of ancient myth and modern science. "Fire of Life" is a wide-ranging investigation and celecbration, in words and pretty pictures, arranged according to reliable coffeetable formula, of that truism.

But truism of any sort is only interesting when delivered with some panache. And this book -- containing many fascinating bits of information, several important points of sociopolitical good sense, yet also something to bore everyone -- suffers from the lack of authorial panache. In fact, it suffers from the lack of an author.

It was written, instead, by a committee. Twenty-eight individuals, most of them, scientists and many of them astronomers, contributed chapters on a broad spectrum of subjects all having to do somehow, directly or tenuously, with the sun.

There are selections describing theories about the "big bang" and the birth of our galaxy, the majestically orderly process by which a supernova becomes a star, planetary evolution after that, the physics and anatomy of our sun as it exists today in its middle age: These are the book's worthiest offerings.

There is the inevitable treatment of Stonehenge, and another chapter is devoted to solar ritual among the Pueblo Indians. Also, unexpectedly charming essays on bizarre optical phenomena (rainbows, "sun dogs," coronas, circumhorizontal arcs) caused by naural sunlight, and on the depiction of sunlight in Romantic and Impressionistic painting. And disquisitons on the supposed role of solar radiation in stirring primordial molecules into the first signs of earthy life, on photosynthesis as it now fuels all plant and animal life on this glove, and on the greenhouse effect as it threatens same. A chapter presents everything you will need to know about sundials. And finally, a five-part section argues very justly the entropic imperative, and the real potential of solar-power technology.

So what's wrong with such a grab bag of solaristic baubles? Nothing at all, exceptt that they do not amount to a book you want to sit down and read.

"It is entirely appropriate that the Smithsonian should bring you a book about the sun," begins the secretary of the institution in his Introduction, and he goes on to support that sonorous claim with an account of the Smithsonian's pioneering role in modern solar research. But perhaps that is just the problem: The book is so appropriatem : decorous and decorative, genteelly but not taxingly informative, predictable, well intentioned, safe, not compelling enough.

Twenty-eight individuals -- most of whom are undoubtedly better scientists than writers -- tell us in 28 ways, with illustrative facts that are welcome and redundant banalities that are not, about how the sun happens to be quite important. Yes, and very hot.