ASTRO-F Infrared Sky Survey mission

摘要

ASTRO-F is the Japanese infrared astronomical satellite. The mission purpose is the infrared sky survey with much higher sensitivities and spatial resolutions than those of the previous survey mission IRAS. The ASTRO-F has a liquid-helium cooled telescope with an aperture of 68.5 cm. The lightweight liquid helium cryostat has been developed for the ASTRO-F. The use of cryocoolers and other design features will realize the cryogen life of 550 days in orbit with only 170-liter liquid helium. The attitude control system provides capabilities of a continuous sky survey and also pointing observations. The absolute accuracy of the attitude control is approximately 10 arcsec, and the stability is better than 1 arcsec. The astronomical data will be sent to the ground in the rate of 4 Mbps through the X-band link. The telemetry data amount to more than 2 GB per day. The planned launch date was February 2004, but it has delayed because of a failure in the mirror support mechanism of the telescope system. Though the new launch date has not been decided formally, the launch in 2005 summer is now targeted.