Reviewed by Jean Worsley Retired Biology Teacher
The book Gravity by Jim Whiting, in the series Mysteries of the Universe, will introduce the reader to philosophers, scientists, and mathematicians who have tried to explain this phenomenon through the ages. Further, they will examine scientific concepts and theories as well as topics of current and future research. The author’s skillful use of color on pages, title, and captions, along with striking photos and pictures will appeal to young readers.
It begins with a familiar statement, “What goes up must come down” due to a force called gravity. Three other forces in nature are briefly defined. A delightful discussion describes the effects of gravity. Weightlessness in space travel is also highlighted. An interesting aside explains how giraffes overcome gravity and how this knowledge played a role in the development of space suits.
It is of interest to note that ancient Greeks believed that phenomena observed in the universe could be explained simply by reasoning. This led to the belief in geocentrism, an Earth–centered universe which prevailed for many centuries. This belief was one of the main obstacles in understanding many phenomena. Finally, early astronomers discovered that the sun was the center of the universe and the concept of heliocentrism was brought to the forefront.
With the invention of the telescope, it was proven that the same force that held objects together on Earth also held celestial bodies. As knowledge expanded, people began to wonder whether or not they could escape gravity and soar into outer space. This idea was perpetuated by science fiction writers and is described in one of the "Gravitational Asides." When scientists learned the speed needed to escape gravity, the space age became a reality. After World War II, rocket research increased and artificial satellites were launched. Today hundreds of satellites have been launched, all depending on gravity, and some are used in weather forecasting and in navigation. Further, as a result of continued calculations and experiments by Copernicus, Kepler, Galileo, Newton, and others, additional laws such as the law of gravitation were formulated.
Today, gravity research is focusing on black holes, dark matter, and on theories to unite the four fundamental forces in the universe. Other projects are also in progress. The author states that the mystery of gravity that remains is how it will ultimately influence the fate of the universe. The book includes an introduction, four chapters, four asides, endnotes, web sites, a bibliography, and an index. This is an excellent resource to introduce this mystery. Further, young readers will become aware of how scientists solve problems and how theories and laws are validated as they build on prior knowledge.
Review posted on 9/6/2012
|