Moon lander SELENE-2 is planed as a follow-on mission of Kaguya (SELENE). The spacecraft is to be launched before the middle of 2010's.
When and how the moon was born? How the moon has been transforming? What is the present state of the moon? There are many riddles on the moon. Kaguya (SELENE) spacecraft which was launched in September, 2007 and is now orbiting around the moon will reveal some of the riddles by its detail remote-sensing observation. However, it is difficult to know the inside of the moon only with remote-sensing technique. How is under the surface? How is the inside of the rocks? How is the interior structure of the moon? SELENE-2 lands on the moon and investigates the surface, the rocks, and the sub-surface of the moon with a mobile robot (rover).
Presently, an international lunar outpost is considered to be constructed in 2020's, where astronauts stay for months. In future, the moon will be used also as astronomical observatories. How is radiation environment on the moon? How lunar surface dust affects machines and human body? How we should prevent from and remove dust? Is the moon surface suitable for constructing buildings? Are there natural resources such as water or construction material? Those researches should be performed before large scale exploration.
Development and validation of lunar exploration technologies are also important. Japan has never performed lunar soft-landing (*1) nor explored on the surface. Those technologies are essential for not only moon but also mars or other planets. Technologies to be developed and demonstrated for SELENE-2, that is, high-precision autonomous landing, obstacle avoidance, or observation technologies under the surface are the frontiers of the exploration technologies in the world. Japan should contribute to international lunar exploration with those technologies.
(*1) Hiten spacecraft hard-landed on the moon in 1993. Hayabusa spacecraft landed on the asteroid Itokawa in 2005.