Makoto YOSHIKAWA

4th Space Debris Workshop(December 16-17, 2010, Chofu Aerospace Center, Japan Aerospace Exploration Agency (JAXA))We are attempting the observations of geostationary space debris using TDI mode. In TDI-mode observations, the positions of geostationary space debris are able to be measured even if field stars appear as long horizontal streaks because of a long exposure. To make the best use of TDI mode, the use of the "image for a positional measurement" and the image subtraction method were examined. Detection limit for TDI observation was evaluated, and limiting magnitude is estimated to be 18.7 (60sec exposure, S/N ca. 5).Physical characteristics: Original contains color illustrations

The asteroid explorer Hayabusa, which is the spacecraft for asteroid sample return mission of Japan, came back to the Earth on June 13, 2010, seven year after the launch. It is the first spacecraft in the world that went to a solar system body farther than the moon, touched down on its surface, took off, and came back to the earth. Hayabusa has many new challenges; some of them were successful but others were unsuccessful. As the results, Hayabusa revealed the strange nature of a small near earth asteroid, Itokawa. In this paper, we describe the whole mission of Hayabusa.

The small solar system bodies, such as asteroids and comets, are important to study the origin and evolution of the solar system and the life. The asteroid explorer "Hayabusa" is the first sample return mission from an asteroid. It will come back to the earth on June 13, 2010. Up to now, Hayabusa got a lot of data from an very small asteroid Itokawa, the size of which is about 500 m, and it brought quite new information for the planetary science. At present (May 2010), we are working for the final operation of Hayabusa, and also we are studying Hayabusa follow-on missions. In the new missions, we will explore small solar system bodies in different type to advance our understanding to the solar system.