Posted by James Glanz on January 28, 2003:

April 13, 2000; Thursday ,National Desk WILLIAM KAULA,73,WHO DREW MAPS OF EARTH USING SATELLITES By: James Glanz William M. Kaula, who used early satellites to create the first truly global maps of Earth's shape and structure, died on April 1 at his home in Los Angeles. He was an emeritus professor of geophysics at the University of California at Los Angeles, and was 73. The cause was cancer, said his wife, Gene Hurley Kaula. Ordinary map making involves knitting together many separate measurements of features like mountains,valleys, and the stength of Earth's gravity. The strength of gravity varies slightly from point to point, reflecting those surface features and also giving hints of structures in the rock beneath the surface. Those same variations in gravity alter the motion of artificial satellites in orbit around Earth. Mr. Kaula (rhymes with Paula) solved the problem of translating those subtle changes into a grand pattern of structure, revealing that over all, Earth is an oblate spheroid with irregular bulges and depressions that cover vast areas of its surface. His solution meant that for the first time, latitude and longitude positions on one continent could be accurately related to positions on another. Not only did that lead to what might be called the first literally global maps, but it also paved the way for practical tasks like firing ballistic missiles accurately from one continent to another. "There was no way to get observations of that nature across the ocean before satellites," said Bernard H. Chovitz, a retired expert in geodesy, the study of Earth's shape and exact distances on its surface. Mr. Chovitz added that Mr. Kaula "was the first one to obtain from satellites a gravitational field and a set of points all connected in a single solution." Mr. Kaula was born in Sidney, Australia, in 1926 and moved with his family to Massachusetts, where he spent most of his childhood. He graduated from the United States Military Academy at West Point with a bachelor's degree in military engineering in 1948, and received a master's degree in geodesy from Ohio State University in 1953. Despite his later prominence in academics, he never obtained a Ph. D, instead learning the tools of advanced research on his own. "He was very proud of that - that he got there without the ticket of admission," said Dr. Margaret Kivelson, a professor of space physics at U.C.L.A. His early research involved using statistics to link scattered measurements of Earth's gravity, made on the ground, into a single pattern, Mr. Chovitz said. But with the launching of the first artificial satellites in the late 1950's, Mr. Kaula began working out the problem of analyzing their orbits to determine the so-called geoid, a shape that gives a measure of how Earth's gravitational field varies. With that analysis in hand, geodicists used photographs of the satellite orbits to go beyond fragmentary measurements made on the ground, said Dr. Gerald Schubert, a professor in the department of earth and space science at U.C.L.A. "By flying overhead and covering all the space around the Earth, you could get a complete, global coverage," he said. Global knowledge of the geoid gave map makers the information they needed to create a single, accurate frame of reference for detailed charts of individual land masses and the seas. Dr. Kaula's book on the subject, "Theory of Satellite Geodesy," first published in 1966 has remained a clasic in the field, Dr. Schubert said. Mr. Kaula later led experiments that used lasers flown aboard several Apollo missions to map the topography of the Moon, and he participated in a related mission that used radar to discover striking surface features such as volcanolike structures and great plateaus on Venus. Besides his wife, he is survived by three children, Anne Shapiro, Jaqueline Kaula and Marie Bloechle; three stepchildren, Don Jensen, Janet Jensen and Patty Schwartz, and nine grandchildren. Known for a potent memory that helped him pull together results from widely disparate fields of research, Mr. Kaula nevertheless constantly jotted down facts that interested him in a small notebook that he always carried. He collected not just scientific facts but also quotations from literature, pithy insights from his colleagues and more mundane matters. "He could look up the amount of fat on a herring if he wanted to," said Dr. Fred Spilhaus, executive director of the American Geophysical Union. "In fact," Dr. Spilhaus said, recalling a discussion with Mr. Kaula about a diet plan, He did once."

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