Overview of the ROCSAT-2 Satellite and ISUAL Instruments

After six years of preparation, ROCSAT-2 - the second satellite from Taiwan was successfully launched on 20 May 2004 from Vandenberg Air Force Base in California. ROCSAT-2 carries two payloads onboard: the Remote Sensing Imager (RSI) to image the ground Earth, and the Imager of Sprites and Upper Atmospheric Lightning (ISUAL) to study the transient luminous phenomena. The ISUAL instruments consist of a low-light level camera, a six-channel spectrophotometer and a red/blue band array photometer. With this set of instruments, ISUAL project seeks to determine the location and timing of upper atmospheric transient events above thunderstorms, to investigate their spatial, temporal and spectral properties, to obtain a global survey of upper atmospheric flashes, and to perform an additional global survey of auroras and airglows. In this talk, the characteristics of the ISUAL payload, the key parameters of ROCSAT-2, the observation strategy of the experiment and some preliminary results will be presented. ISUAL project is an international collaboration supported by the National Space Program Office in Taiwan, with additional contributions from the National Cheng Kung University (NCKU), Taiwan, the Space Science Laboratory of the University of California at Berkeley, and Tohoku University, Japan. The NCKU team is supported in part by research grants from National Space program Office (93-NSPO(B)-ISUAL-FA09-01) and National Science Council (NSC93-2112-M-006-007,, NSC93-2111-M-006-001) in Taiwan.