Development of a superconducting submillimeter-wave limb emission sounder (SMILES) on the Japanese Experiment Module (JEM) of the International Space Station (ISS)

Abstract

NASDA and CRL are planning to develop a spaceborne SMILES, which is to be installed in the Exposed Facility (EF) on the JEM of the ISS. By observing gases such as C O, HC , NO, N 2 O, HO 2 and BrO in the stratosphere, JEM/SMILES can trace the chemical reactions concerning the ozone depletion and climate change. Global distribution of those gases will be mapped with a height resolution of about 2 km. JEM/SMILES receives low-intensity signals from those gases with highly sensitive SIS (Superconductor-Insulator-Superconductor) mixers at 640 GHz, which are cooled to 4.2 K by a space-qualified mechanical cooler. The mission target is to demonstrate the effectiveness of the submillimeter-wave limb emission sounding and to establish space applicability of the low-noise SIS mixers and a mechanical 4-K cooler. JEM/SMILES is expected to be launched in 2003, and the experiments will last a year or more.