目前日本已在着手实施空间站操作、研制载人飞行的基础设施和把航天器送往月球、火星和金星等航天计划。 日本在种子岛完成了大规模新型发射设施的建设工作,并正在研制新型H-2和M-5运载火箭,另外还在设计新型的航天器,这一切都象征着日本21世纪的航天活动意向。 然而,随着日本加快实施航天计划的步伐,它正面临着开发航天技术所带来的高费用、时间跨度大和其它诸多难题。日本的 At present, Japan is already embarking on the operation of the space station, developing the manned flight infrastructure and delivering the spacecraft to space programs such as the Moon, Mars and Venus. Japan has completed the construction of a large-scale new launch facility on Tanegashima and is developing new H-2 and M-5 launch vehicles and designing new spacecraft, all of which symbolize Japan’s intention of space activities in the 21st century . However, as Japan speeded up the implementation of its space program, it was facing the high cost, time-spans and other challenges associated with the development of space technology. Japan’s