Argues that a manned expedition to Mars could cost less than one- tenth of the $400 billion cited by NASA, is possible with existing technology and expertise, could be funded with a combination of public and private money, is not as dangerous as some think, and is necessary to explore the planet thoroughly. The trick is to use resources on Mars to produce the fuel, oxygen, food, ceramics, plastics, and metals needed to turn an expedition into a permanent colony. Annotation copyrighted by Book News, Inc., Portland, OR