Hakucho
Hakucho (CORSA-b)
Mission Descriptions
Mission Overview
The "Hakucho (CORSA-b)" satellite was the first X-ray astronomy satellite launched by the Institute of Space and Astronautical Science (ISAS) of Japan on February 21, 1979. Its mission was to observe X-ray burst sources and to obtain the broad-spectrum and intensity variations of X-ray celestial objects.
The satellite, weighing 96 kg, was injected by M-3C-4 into a circular orbit with a perigee of 545 km and an apogee of 577 km, inclination of 30 degrees, and period of 96 minutes. Utilizing the Earth's magnetic field to control its spin axis, the satellite observed numerous X-ray sources. Operations were terminated on April 15, 1985.
From DARTS, only raw telemetry data archives are available. Higher-level processed data, documentation necessary for data processing, and software for scientific analysis are not provided, which limits comprehensive scientific analysis support.
Achievements
Eight new X-ray burst sources were discovered by the modulation collimator onboard Hakucho. This has provided new insights into the physical properties of X-ray bursts and the mechanisms of their bursts. It also played an active role in simultaneous observations with optical observatories around the world.
Other observations included periodic variations of X-ray pulsars and black holes, which greatly contributed to the development of early X-ray astronomy and provided an important foundation for subsequent research.