PASADENA, Calif.—If you're still shopping for a Christmas present to give to that flaky uncle, how about giving him the flakiest book in science?
The Snowflake: Winter's Secret Beauty, by California Institute of Technology professor of physics Ken Libbrecht and Wisconsin photographer Patricia Rasmussen, takes an elegant look at the humble flake of snow, from the viewpoint of the scientist as well as the artist.
Containing numerous full-color photographs, the book provides an in-depth look at a frozen phenomenon of nature that is still, perhaps surprisingly, not completely understood.
Libbrecht believes the photo-micrographs in the book are the best that have ever been taken of snowflakes. He began his collaboration with Rasmussen by building her a special camera and hauling it halfway across the country to her studio. She was already an avid snowflake photographer before contacting Libbrecht—perhaps the world's leading authority on snowflake formation—but was relying on conventional photography equipment, which Libbrecht says just isn't quite good enough.
"Patty had the snow and the photographic know-how, and I had the optical knowledge," said Libbrecht in a recent interview in his office on the Caltech campus. "It was a very successful collaboration.
"The proof is in the pudding," he added. "The pictures are substantially better than any snowflake images that have ever been captured before."
In addition to the many stunning plates of snowflakes in dazzling colors, the book also contains a nontechnical discussion of crystal formation in general, snow-crystal symmetry, a "field guide to falling snow," and, of course, a detailed answer to the perennial question of whether any two snowflakes are exactly alike.
"The short answer is yes and no," says Libbrecht. "If you look closely enough, there will always be differences, but sometimes you have to look pretty closely."
In many cases, there are very clear differences between snow crystals, and what's more, there are several very distinct forms the crystals can take. In fact, this is one of the issues that Libbrecht addresses when using the experimental "cold chambers" in his Caltech physics lab to create "designer" snowflakes.
Depending primarily on very subtle changes in temperature and humidity, snow crystals falling from the sky grow into different shapes—small plates just below freezing, pencil-like columns of ice a few degrees colder, and large, ornate plates at about –15 o C (5 o F). The ones most favored by photographers have names like "stellar dendrites" and "sectored plates," some possessing a near-perfect symmetry that can put the best human-made glass chandelier to shame.
Libbrecht can grow these different snowflake forms at will in his lab, but says there are still subtle issues that are of interest to physicists who make it their business to control the formation of crystals of various materials. A real-world application of research on crystals is the growth of semiconductors for our electronic gadgets, which are made possible in part by painstakingly controlling how certain substances condense into solid structures.
"In the case of snowflakes, there are pieces to the puzzle that are not understood yet," Libbrecht says. "But when you're a researcher, you're happy to see this. You don't want to work on a problem that's already solved."
As for the reason anyone would spend enough time on snowflakes for an entire book, Rasmussen's afterword perhaps gives a clue: "For me, snow-crystal photography is an escape from the stress of modern life into a sanctum of beauty and wonder and solitude. It's a treasure hunt. It's a photographic harvest from nature's bounty."
The Snowflake: Winter's Secret Beauty, is now available in bookstores and on the Web. The book is published by Voyageur Press. For a review copy, call Dorothy Molstad at 800-837-2210, ext. 24.
