History of Radio Astronomy Research in Japan as Having Led to Its Global Position : Emphasizing on Scientific Goals and the Equipment Development at Nobeyama Radio Observatory

Abstract

In the 1960s, radio astronomy research in Japan was at a developing stage in comparison with that of leading countries. However, in the following decades the situation improved dramatically, and Japan gained a competitive position in this research field. This was achieved largely through the construction of the Nobeyama Radio Observatory (NRO). This paper describes the NROʼs construction history by focusing on the setting of scientific goals and development of the equipment to achieve them. Although there have been a few preceding studies on the Japanese history of modern astronomy including radio astronomy, it is characterized that this study utilized mainly the minutes of the Science Council of Japan and documents of research groups as primary sources. This paper clarifies the following processes. In the 1960s, with a series of major worldwide discoveries in radio astronomy, the importance of radio astronomy was recognized in Japan as well, which led to the planning of the Science Council of Japan. Responding to the global trend of radio astronomy, Japan set as the scientific goal exploring millimeter-wave astronomy. In order to meet the requirements, the 45m radio telescope and an acousto-optic radio spectrometer for spectral observations were designed and their specifications were actually realized, which far exceeded world standards at that time. Consequently, Japanese radio astronomy could obtain its global position.