[Gravitational biology of integrative organisms and ecological system--the road map of space activities]

History of the International Space Station, ISS, and planning of its scientific use are described in this essay. Fundamental gravitational biology and its facility on the ISS have been identified to have the highest priority to conduct scientific experiments with variable G environment in orbit. The road map of space activities is clearly directing the efforts toward manned Mars exploration. The Centrifuge is a core element of the facilities dedicated to this endeavor. Several research subjects are discussed with the results obtained from the past space experiments. Direct effects of gravity on the biological system at the level of integrative organisms are major subjects of study that will be conducted on the large scaled centrifuge.