In the past decade, great progress has been made in submillimeter receiver technology. The superconductor-insulator-superconductor (SIS) mixer has demonstrated ultra-low noise performance in a large frequency range up to 1, 000GHz. A breakthrough has been made with a new superconducting hot-electron bolometer (HEB) mixer that realizes a low-noise mixer even beyond 1, 000GHz. Such progress in submillimeter mixers, combined with the progress in submillimeter signal sources and low-noise IF amplifiers, has made many scientific programs in astronomy and earth atmospheric research feasible. Because of the large opacity of the atmosphere, submillimeter observation will be successful only on high mountains with extremely low humidity or in space above the earth's atmosphere. In Japan, a small submillimeter telescope, which was developed to find the distribution of interstellar neutral atomic carbon in the Milky Way Galaxy, is now under construction and scheduled to go into operation on the top of Mt. Fuji. Towards the future, on the other hand, there is a big plan for a next-generation radio telescope, called the Large-Millimeter and Submillimeter Array (LMSA), which is being investigated by Japanese astronomers. The LMSA, when built on a high mountain site overseas, under good atmospheric conditions, will have the remarkable capability to take a fine image of distant astronomical objects with a resolution of 0.1 to 0.01 arcseconds. Submillimeter observation from space will be quite fruitful both for astronomy and for atmospheric research. A small satellite, SWAS, was developed by NASA to observe the oxygen molecules and water vapor in interstellar space. European Space Agency (ESA) has a long-term project, FIRST, in which the objective is to build a 3-m telescope in space for far-infrared and submillimeter astronomy. Swedish scientists have built a small satellite, ODIN, for astronomy and aeronomy. The JEM/SMILES, which is proposed by NASDA and Communications Research Laboratory (CRL) as an experiment for the International Space Station, is a challenging mission to demonstrate the advantages of using a combination of submillimeter SIS mixer and closed-cycle cryogenic cooler for atmospheric observations.
Activity on the international standardization of the test methods for industrial superconductors is introduced, which is authorized by IEC/TC90 (Superconductivity). A brief history and strategy of the organization are explained. The substantial work involved to discuss and prepare the draft for each item is left to the respective international working group. At present, 8 working groups cover the field of superconductivity and related properties; terminology, critical current, residual resistance ratio, copper ratio, mechanical property and surface resistance. One of them, the test method of critical current for Cu/Nb-Ti composite superconductors, will soon be published as an international standard. The domestic activity in Japan supporting international standardization is supervised by the Japanese National Committee of IEC/TC90. The mission of the JNC is the following three activities; support of the international activity as a secretary country, translation of international standards to JIS and supervision of domestic activities. The actual test methods are proposed and carried out by the New Materials Center and Japanese Fine Ceramics Association. It is emphasized that establishing good liaison with groups such as VAMAS concerning the fundamental aspects of standardization is crucial to promote effective international collaboration.