The word "laser" is an acronym for "light amplification by the stimulated emission of radiation." The laser is a unique device that produces a very pure color of light that is concentrated into a pencil-thin beam that stays concentrated, or focused, as it travels.

Lasers are commonly seen in several ordinary commercial applications, such as bar code scanners, laser pointers, CD players, CD-ROMs, videodiscs, laser surgery, and laser-light shows. However, lasers have many other applications as well. For instance, lasers enable us to communicate and transfer massive amounts of information, monitor our environments, provide protection from aggressive military attacks, and probe the deepest reaches of space and understand the origins of the universe. Lasers will have a myriad of applications in space, the following of which will be highlighted: (1) laser communications, (2) lasers for environmental and remote sensing, (3) space-based laser defense systems, and (4) lasers for...