Robert A. Citron, a space visionary who helped commercialize space, had died in Washington, his family announced. Citron, 79, died Jan. 31 of complications of prostate cancer at his Bellevue home, his son Kirk told the Los Angeles Times. After a varied career that included founding an adventure travel agency, building satellite tracking stations and producing television documentaries, Citron began to focus on space in the early 1980s. \"Everybody laughed at him\" for advocating space tourism, said Citron\'s brother Rick, a Los Angeles attorney. In 1983 he developed Spacehab, a pressurized module that fit inside the cargo bay of the space shuttle and was used to hold scientific experiments on more than 20 space shuttle missions. One of Citron\'s most important contributions was showing the private sector could create space hardware far more cheaply than the government, constructing two Spacehabs for $150 million, far less than NASA\'s estimates of $1.2 billion, experts said. \"The power of Bob\'s ideas, technical designs and business concepts made space business, including businesses involving humans in space, more real,\" said James A.M. Muncy, a space policy consultant in Washington.