ASCA Special Exhibit
A model of international collaboration
The Institute of Space and Astronautical Sciences (ISAS) is the central research institute for space and astronautical science in Japan. ISAS has been launching scientific satellites since 1970, at a rate of roughly one satellite per year. X-ray astronomy has become one of the major research areas for ISAS, with the successful launches of Hakucho (1979), Tenma (1983), and Ginga (1987).
The ASCA satellite in the clean room prior to launch. (Credit: ISAS)
Even with such a strong tradition and a large accumulation of expertise at ISAS and at several major Japanese universities, they felt they could benefit greatly from an international collaboration for their 4th X-ray astronomy satellite, in this case with the US. This was partly due to the sheer increase in complexity and sophistication of the satellite they hoped to build. Additionally, there were specific areas in which the US had a clear lead over Japan. By forging a collaboration between US and Japanese groups, they hoped to create new centers of expertise in several new areas.
From the US point of view, the collaboration with ISAS provided an opportunity to participate in a mission that would be developing and utilizing new technology. Although the launch capabilities of ISAS rockets were modest, they had been reliable. ISAS also had an unparalleled reputation for on-time completion of their projects. On the other hand, NASA had temporarily gotten away from regular launch opportunities for small and medium sized satellites, during the 1980s and the early 1990s.
NASA's contribution to ASCA was in the conical foil X-ray mirrors, in the X-ray CCD cameras, and in software. In return, US scientists have enjoyed access to 40 percent of observing time on ASCA; 15 percent of the total observing time is reserved for the exclusive use of the US guest observers, and an additional 25 percent of time is earmarked for collaborative US-Japanese observations. The latter block of time has successfully fostered many collaborations among scientists from the US and Japan.
Published: February 1998
Text Reviewed: September 2018